Acutus Medical (AFIB) 10-K19 Mar 212020 FY Annual reportFinancial data

Company Profile

Cover Page

Cover Page - USD ($)	12 Months Ended
Cover Page - USD ($)	Dec. 31, 2020	Mar. 15, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Registrant Name	ACUTUS MEDICAL, INC.
Entity Central Index Key	0001522860
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer	No
Entity Public Float			$ 0
Entity Common Stock, Shares Outstanding		28,095,004
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity File Number	001-39430
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-1306615
Entity Address, Address Line One	2210 Faraday Ave.
Entity Address, Address Line Two	Suite 100
Entity Address, City or Town	Carlsbad
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92008
City Area Code	442
Local Phone Number	232-6080
Document Annual Report	true
Document Transition Report	false
ICFR Auditor Attestation Flag	false
Title of 12(b) Security	Common stock, par value $0.001 per share
Trading Symbol	AFIB
Security Exchange Name	NASDAQ
Documents Incorporated by Reference	Part III of this Annual Report on Form 10-K incorporates certain information by reference from the definitive proxy statement for the Registrant’s 2021 Annual Meeting of Stockholders to be filed within 120 days of the Registrant’s fiscal year ended December 31, 2020 (the “Proxy Statement”). Except with respect to information specifically incorporated by reference in this Form 10-K, the Proxy Statement is not deemed to be filed as part of this Form 10-K.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 25,234,000	$ 9,452,000
Marketable securities, short-term	105,839,000	62,351,000
Restricted cash	150,000	150,000
Accounts receivable	2,160,000	263,000
Inventory	12,958,000	8,424,000
Prepaid expenses and other current assets	5,047,000	1,816,000
Total current assets	151,388,000	82,456,000
Marketable securities, long-term	8,726,000
Property and equipment, net	12,356,000	4,427,000
Right-of-use asset, net	1,669,000	2,341,000
Intangible assets, net	5,653,000	4,110,000
Goodwill	12,026,000	12,026,000
Other assets	717,000	95,000
Total assets	192,535,000	105,455,000
Current liabilities:
Accounts payable	8,266,000	3,882,000
Accrued liabilities	7,308,000	10,076,000
Contingent consideration, short-term	5,400,000	8,200,000
Operating lease liabilities, short-term	933,000	833,000
Common and preferred stock warrant liability		8,919,000
Total current liabilities	21,907,000	31,910,000
Operating lease liabilities, long-term	1,134,000	2,054,000
Long-term debt	39,011,000	38,244,000
Contingent consideration, long-term	3,900,000	5,700,000
Total liabilities	65,952,000	77,908,000
Commitments and contingencies (Note 12)
Stockholders' equity (deficit)
Preferred stock, $0.001 par value; 5,000,000 shares authorized December 31, 2020 and no shares authorized as of December 31, 2019; no shares issued and outstanding as of December 31, 2020 and 2019
Common stock, $0.001 par value; 260,000,000 and 220,000,000 shares authorized as of December 31, 2020 and 2019, respectively; 27,991,425 and 695,902 shares issued and outstanding as of December 31, 2020 and 2019, respectively	28,000	1,000
Additional paid-in capital	487,290,000	33,252,000
Accumulated deficit	(361,015,000)	(259,034,000)
Accumulated other comprehensive income (loss)	280,000	(30,000)
Total stockholders' equity (deficit)	126,583,000	(225,811,000)
Total liabilities, convertible preferred stock and stockholders' equity (deficit)	$ 192,535,000	105,455,000
Series A Convertible Preferred Stock [Member]
Convertible preferred stock
Convertible preferred stock		3,059,000
Series B Convertible Preferred Stock [Member]
Convertible preferred stock
Convertible preferred stock		40,685,000
Series C Convertible Preferred Stock [Member]
Convertible preferred stock
Convertible preferred stock		74,575,000
Series D Convertible Preferred Stock [Member]
Convertible preferred stock
Convertible preferred stock		$ 135,039,000

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Preferred Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	5,000,000	0
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Common Stock, Shares Authorized	260,000,000	220,000,000
Common Stock, Shares, Issued	27,991,425	695,902
Common Stock, Shares, Outstanding	27,991,425	695,902
Series A Convertible Preferred Stock [Member]
Convertible Preferred Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Convertible Preferred Stock, Shares Authorized	0	3,848,696
Convertible Preferred Stock, Shares Issued	0	391,210
Convertible Preferred Stock, Shares Outstanding	0	391,210
Convertible Preferred Stock, Liquidation Preference, Value		$ 3,245
Series B Convertible Preferred Stock [Member]
Convertible Preferred Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Convertible Preferred Stock, Shares Authorized	0	30,032,100
Convertible Preferred Stock, Shares Issued	0	3,088,444
Convertible Preferred Stock, Shares Outstanding	0	3,088,444
Convertible Preferred Stock, Liquidation Preference, Value		$ 41,294
Series C Convertible Preferred Stock [Member]
Convertible Preferred Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Convertible Preferred Stock, Shares Authorized	0	48,184,000
Convertible Preferred Stock, Shares Issued	0	4,499,921
Convertible Preferred Stock, Shares Outstanding	0	4,499,921
Convertible Preferred Stock, Liquidation Preference, Value		$ 75,000
Series D Convertible Preferred Stock [Member]
Convertible Preferred Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Convertible Preferred Stock, Shares Authorized	0	90,000,000
Convertible Preferred Stock, Shares Issued	0	8,200,297
Convertible Preferred Stock, Shares Outstanding	0	8,200,297
Convertible Preferred Stock, Liquidation Preference, Value		$ 136,675

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenue	$ 8,464,000	$ 2,836,000
Costs and operating expenses:
Cost of products sold	15,889,000	9,243,000
Research and development	33,454,000	23,029,000
Selling, general and administrative	50,357,000	26,847,000
Impairment of property and equipment	0	786,000
Change in fair value of contingent consideration	97,000	500,000
Total costs and operating expenses	99,797,000	75,405,000
Loss from operations	(91,333,000)	(72,569,000)
Other income (expense):
Change in fair value of warrant liability and embedded derivative	(5,555,000)	(1,919,000)
Loss on debt extinguishment		(1,447,000)
Interest income	436,000	1,164,000
Interest expense	(5,506,000)	(22,268,000)
Total other expense, net	(10,625,000)	(24,470,000)
Loss before income taxes	(101,958,000)	(97,039,000)
Income tax expense	23,000	0
Net loss	(101,981,000)	(97,039,000)
Other comprehensive income (loss)
Unrealized (loss) gain on marketable securities	(53,000)	46,000
Foreign currency translation adjustment	363,000	(96,000)
Comprehensive loss	$ (101,671,000)	$ (97,089,000)
Net loss per common share, basic and diluted	$ (8.94)	$ (144.41)
Weighted average shares outstanding, basic and diluted	11,407,542	671,953
License Acquired [Member]
Costs and operating expenses:
Research and development		$ 15,000,000

Consolidated Statements of Conv

Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Series A Convertible Preferred Stock [Member]	Series B Convertible Preferred Stock [Member]	Series C Convertible Preferred Stock [Member]	Series D Convertible Preferred Stock [Member]
Beginning balances at Dec. 31, 2018						$ 3,059	$ 40,685	$ 74,575
Beginning balances, Shares at Dec. 31, 2018						388,558	3,088,444	4,499,921
Beginning balances at Dec. 31, 2018	$ (131,824)	$ 1	$ 30,150	$ (161,995)	$ 20
Beginning balances, Shares at Dec. 31, 2018		656,654
Unrealized (loss) gain on marketable securities	46				46
Foreign currency translation adjustment	(96)				(96)
Issuance of Series A preferred stock for cashless warrant exercise						2,652
Issuance of Series D convertible preferred stock for cash, net of issuance costs									$ 66,563
Issuance of Series D convertible preferred stock for cash, net of issuance costs, Shares									4,091,819
Issuance of Series D convertible preferred stock for 2018 Convertible Notes and 2019 Convertible Notes									$ 68,476
Issuance of Series D convertible preferred stock for 2018 Convertible Notes and 2019 Convertible Notes, Shares									4,108,478
Stock-based compensation	2,994		2,994
Stock-based compensation, shares		11,449
Stock option exercises	108		108
Stock option exercises, shares		27,799
Net loss	(97,039)			(97,039)
Ending balances at Dec. 31, 2019						$ 3,059	$ 40,685	$ 74,575	$ 135,039
Ending balances, shares at Dec. 31, 2019						391,210	3,088,444	4,499,921	8,200,297
Ending balances at Dec. 31, 2019	(225,811)	$ 1	33,252	(259,034)	(30)
Ending balances, shares at Dec. 31, 2019		695,902
Unrealized (loss) gain on marketable securities	(53)				(53)
Foreign currency translation adjustment	363				363
Issuance of Series D convertible preferred stock for the Biotronik Asset Purchase									$ 5,000
Issuance of Series D convertible preferred stock for the Biotronik Asset Purchase, Shares									273,070
Issuance of Series D convertible preferred stock for the contingent consideration related to the Rhythm Xience Acquisition									$ 2,197
Issuance of Series D convertible preferred stock for the contingent consideration related to the Rhythm Xience Acquisition, Shares									119,993
Conversion of convertible preferred stock into common stock upon IPO	260,555	$ 17	260,538			$ (3,059)	$ (40,685)	$ (74,575)	$ (142,236)
Conversion of convertible preferred stock into common stop upon IPO, shares		16,572,935				(391,210)	(3,088,444)	(4,499,921)	(8,593,360)
Issuance of common stock for cash, net of issuance costs of $16,361	166,286	$ 10	166,276
Issuance of common stock for cash, net of issuance cost of $16,361, shares		10,147,058
Reclassification of warrant liability to stockholders' equity	14,474		14,474
Stock-based compensation	12,103		12,103
Stock-based compensation, shares		319,420
Stock option exercises	634		634
Stock option exercises, shares		124,938
Warrant exercise	13		13
Warrant exercise, Shares		131,172
Net loss	(101,981)			(101,981)
Ending balances, shares at Dec. 31, 2020						0	0	0	0
Ending balances at Dec. 31, 2020	$ 126,583	$ 28	$ 487,290	$ (361,015)	$ 280
Ending balances, shares at Dec. 31, 2020		27,991,425

Consolidated Statements of Co_2

Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Series D Convertible Preferred Stock [Member]
Payments of Stock Issuance Costs		$ 1,636
Common Stock [Member]
Payments of Stock Issuance Costs	$ 16,361

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
Consolidated Statements of Cash Flows - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities
Net loss	$ (101,981,000)	$ (97,039,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	2,763,000	2,280,000
Amortization of intangible assets	457,000	250,000
Stock-based compensation expense	12,103,000	2,994,000
Amortization of premiums/(accretion of discounts) on marketable securities, net	484,000	(153,000)
Amortization of debt issuance costs	767,000	17,579,000
Amortization of right-of-use assets	684,000	637,000
Research and development - license acquired		15,000,000
Impairment of property and equipment	0	786,000
Loss on debt extinguishment		1,447,000
Change in fair value of warrant liability and embedded derivative	5,555,000	1,919,000
Change in fair value of contingent consideration	97,000	500,000
Changes in operating assets and liabilities, net of effect from business combination:
Accounts receivable	(1,897,000)	(96,000)
Inventory	(3,891,000)	(5,421,000)
Prepaid expenses and other current assets	(3,383,000)	(928,000)
Other assets	(622,000)	(8,000)
Accounts payable	2,283,000	2,111,000
Accrued liabilities	2,232,000	2,901,000
Operating lease liabilities	(820,000)	(745,000)
Net cash used in operating activities	(85,169,000)	(55,986,000)
Cash flows from investing activities
Purchases of available-for-sale marketable securities	(114,694,000)	(68,735,000)
Sales of available-for-sale marketable securities	17,095,000
Maturities of available-for-sale marketable securities	45,000,000	14,700,000
Purchases of property and equipment	(11,225,000)	(3,395,000)
Purchase of research and development license		(10,000,000)
Cash paid, net of cash acquired for the Rhythm Xience Acquisition		(3,000,000)
Net cash used in investing activities	(63,824,000)	(70,430,000)
Cash flows from financing activities
Proceeds from issuance of debt and warrants		77,000,000
Repayment of debt		(15,000,000)
Payment of issuance and extinguishment costs related to debt		(2,332,000)
Payment of contingent consideration	(2,500,000)
Proceeds from issuance of convertible preferred stock, net of issuance costs		66,563,000
Proceeds from warrants exercises	13,000
Proceeds from issuance of common stock upon IPO, net of issuance costs	166,286,000
Proceeds from stock options exercises	634,000	108,000
Net cash provided by financing activities	164,433,000	126,339,000
Effect of exchange rate changes on cash, cash equivalents and restricted cash	342,000	(96,000)
Net change in cash, cash equivalents and restricted cash	15,782,000	(173,000)
Cash, cash equivalents and restricted cash, at the beginning of the period	9,602,000	9,775,000
Cash, cash equivalents and restricted cash, at the end of the period	25,384,000	9,602,000
Supplemental disclosure of cash flow information:
Cash paid for interest	4,676,000	3,593,000
Supplemental disclosure of noncash investing and financing activities:
Issuance of Series D convertible preferred stock for 2018 Convertible Notes and 2019 Convertible Notes		68,476,000
Issuance of Series D convertible preferred stock for Biotronik asset purchase	5,000,000
Issuance of Series D convertible preferred stock for Rhythm Xience Acquisition	2,197,000
Change in unrealized (gain) loss on marketable securities	53,000	(46,000)
Right-of-use assets exchanged for operating lease liabilities		2,978,000
Accrued purchase of research and development-license		5,000,000
Accrued licensed intangibles assets	2,000,000
Unpaid purchases of property and equipment	101,000	$ 174,000
Transfer of property and equipment to inventory	643,000
Conversion of convertible preferred stock into common stock upon IPO	260,555,000
Reclassification of warrant liability to stockholders' equity	$ 14,474,000

Organization and Description of

Organization and Description of Business	12 Months Ended
Organization and Description of Business	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization and Description of Business	Note 1—Organization and Description of Business Acutus Medical, Inc. (the “Company”) is an arrhythmia management company focused on improving the way cardiac arrhythmias are diagnosed and treated. The Company designs, manufactures and markets a range of tools for catheter-based ablation procedures to treat various arrhythmias. The Company’s product portfolio includes novel access sheaths, transseptal crossing tools, diagnostic and mapping catheters, ablation catheters, mapping and imaging consoles and accessories, as well as supporting algorithms and software programs. The Company was incorporated in the state of Delaware on March 25, 2011, and is located in Carlsbad, California. Liquidity and Capital Resources The Company has limited revenue, has incurred operating losses since inception and expects to continue to incur significant operating losses for at least the next several years and may never become profitable. As of December 31, 2020 and 2019, the Company had an accumulated deficit of $361.0 million and $259.0 million, respectively, and working capital of $129.5 million and $50.5 million, respectively. The Company has historically funded its operations primarily through the sale of debt and equity securities, as well as other indebtedness. With the closing of the Company’s initial public offering (“IPO”), the Company’s current cash, cash equivalents and marketable securities are sufficient to fund operations for at least the next 12 months. However, the Company may need to raise additional funds through one or more of the following: issuance of additional debt, equity or both. Until such time, if ever, the Company can generate revenue sufficient to achieve profitability, the Company expects to finance its operations through equity or debt financings, which may not be available to the Company on the timing needed or on terms that the Company deems to be favorable. To the extent that the Company raises additional capital through the sale of equity or convertible debt securities, the ownership interest of its stockholders will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of common stockholders. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting the Company’s ability to take specific actions, such as incurring additional debt, making acquisitions or capital expenditures or declaring dividends. If the Company is unable to maintain sufficient financial resources, its business, financial condition and results of operations will be materially and adversely affected. The Company may be required to delay, limit, reduce or terminate its product discovery and development activities or future commercialization efforts. There can be no assurance that the Company will be able to obtain the needed financing on acceptable terms or at all.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
Summary of Significant Accounting Policies	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 2—Summary of Significant Accounting Policies Basis of Presentation The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Principles of Consolidation The consolidated financial statements include the accounts of Acutus Medical, Inc. and its wholly-owned subsidiary Acutus Medical NV (“Acutus NV”), which was incorporated under the laws of Belgium in August 2013. All intercompany balances and transactions have been eliminated in consolidation. Use of Estimates and Assumptions The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue, expenses and disclosures of contingent assets and liabilities. The most significant estimates and assumptions in the Company’s consolidated financial statements include, but are not limited to, revenue recognition, useful lives of intangible assets, assessment of impairment of goodwill, provisions for income taxes, measurement of operating lease liabilities, and the fair value of common stock, stock options, warrants, embedded derivative in convertible notes, intangible assets, contingent consideration and goodwill. These estimates and assumptions are based on current facts, historical experience and various other factors believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and the recording of revenue and expenses that are not readily apparent from other sources. Actual results could differ from those estimates. Segments Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business in one operating segment. Cash and Cash Equivalents and Restricted Cash The Company considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. All of the Company’s cash equivalents have liquid markets and high credit ratings. The Company maintains its cash in bank deposits and other accounts, the balances of which, at times and as of December 31, 2020 and 2019, exceeded federally insured limits. Restricted cash serves as collateral for the Company’s corporate credit card program. The following table reconciles cash and restricted cash in the consolidated balance sheets to the totals shown on the consolidated statements of cash flows (in thousands). December 31, December 31, 2020 2019 Cash and cash equivalents $ 25,234 $ 9,452 Restricted cash 150 150 Total cash, cash equivalents and restricted cash $ 25,384 $ 9,602 Marketable Securities The Company considers its debt securities to be available-for-sale securities. Available-for-sale securities are classified as cash equivalents, short-term marketable securities or long-term marketable securities based on the maturity date at time of purchase and their availability to meet current operating requirements. Marketable securities that mature in three months or less from the date of purchase are classified as cash equivalents. Marketable securities, excluding cash equivalents, that mature in one year or less are classified as short-term available-for-sale securities and are reported as a component of current assets. Securities that are classified as available-for-sale are measured at fair value with temporary unrealized gains and losses reported in other comprehensive loss, and as a component of stockholders’ equity (deficit) until their disposition or maturity. See “Fair Value Measurements” below. The Company reviews all available-for-sale securities at each period end to determine if they remain available-for-sale based on the Company’s current intent and ability to sell the security if it is required to do so. Realized gains and losses from the sale of marketable securities, if any, are calculated using the specific-identification method. Marketable securities are subject to a periodic impairment review. The Company may recognize an impairment charge when a decline in the fair value of investments below the cost basis is determined to be other-than-temporary. In determining whether a decline in market value is other-than-temporary, various factors are considered, including the cause, duration of time and severity of the impairment, any adverse changes in the investees’ financial condition and the Company’s intent and ability to hold the security for a period of time sufficient to allow for an anticipated recovery in market value. Declines in value judged to be other-than-temporary are included in the Company’s consolidated statements of operations and comprehensive loss. The Company did not record any other-than-temporary impairments related to marketable securities in the Company’s consolidated statements of operations and comprehensive loss for the Concentrations of Credit Risk and Off-Balance Sheet Risk Financial instruments that potentially subject the Company to credit risk consist principally of cash, cash equivalents, restricted cash, accounts receivable and marketable securities. Cash and restricted cash are maintained in accounts with financial institutions, which, at times may exceed the Federal depository insurance coverage of $0.25 million. The Company has not experienced losses on these accounts and management believes, based upon the quality of the financial institutions, that the credit risk with regard to these deposits is not significant. The Company’s marketable securities portfolio consists primarily of investments in money market funds, commercial paper, U.S. treasury securities, asset-backed securities and short-term high credit quality corporate debt securities. Revenue from Contracts with Customers The Company accounts for revenue earned from contracts with customers under Accounting Standards Codification (“ASC”) 606, Revenue from Contracts with Customers • Step 1: Identify the contract with the customer. • Step 2: Identify the performance obligations in the contract. • Step 3: Determine the transaction price. • Step 4: Allocate the transaction price to the performance obligations in the contract. • Step 5: Recognize revenue when, or as, the company satisfies a performance obligation. The Company usually places its medical diagnostic equipment, AcQMap System, at customer sites under loan agreements and generates revenue from the sale of disposable products used with the AcQMap System. Disposable products include AcQMap Catheters and AcQGuide Steerable Sheaths. The Company provides the disposable products in exchange for consideration, which occurs when a customer submits a purchase order and the Company provides disposables at the agreed upon prices in the invoice. Generally, customers purchase disposable products using separate purchase orders after the equipment has been provided to the customer for free with no binding agreement or requirement to purchase any disposable products. The Company also sells the AcQMap System to customers along with software updates on a when-and-if-available basis and equipment service. The Company has elected the practical expedient and accounting policy election to account for the shipping and handling as activities to fulfill the promise to transfer the disposable products and not as a separate performance obligation. During the year ended December 30, 2020, the Company entered into deferred equipment agreements that are generally structured such that the Company agrees to provide an AcQMap System at no up-front charge, with title of the device transferring to the customer at the end of the contract term, in exchange for the customer’s commitment to purchase disposables at a specified price over the term of the agreement, which generally ranges from two to four years. The Company determined that the deferred equipment agreements include embedded sales-type leases. The Company allocates contract consideration under deferred equipment agreements containing fixed annual disposable purchase commitments to the underlying lease and non-lease components at contract inception. The Company expenses the cost of the device at the inception of the agreement and records a financial lease asset equal to the gross consideration allocated to the lease. The lease asset will be reduced by payments for minimum disposable purchases that are allocated to the lease. The following table sets forth the Company’s revenue for disposables, systems, and service/other for the years ended December 31, 2020 and 2019 (in thousands): Year Ended December 31, 2020 2019 Acutus Direct Disposables $ 5,221 $ 2,764 Systems 1,660 — Service/Other 91 19 Total Acutus direct revenue 6,972 2,783 Distribution agreements 1,492 53 Total revenue $ 8,464 $ 2,836 The Company’s contracts only include fixed consideration. There are no discounts, rebates, returns or other forms of variable consideration. Customers are generally required to pay within 30 to 60 days. The delivery of disposable products are performance obligations satisfied at a point in time. The disposable products are shipped Free on Board (“FOB”) shipping point or FOB destination. For disposable products that are shipped FOB shipping point, the customer has the significant risks and rewards of ownership and legal title to the assets when the disposable products leave the Company’s shipping facilities, thus the customer obtains control and revenue is recognized at that point in time. Revenue is recognized on delivery for disposable products shipped via FOB destination. The installation and delivery of the AcQMap System is satisfied at a point in time when the installation is complete, which is when the customer can benefit and has control of the system. The Company’s software updates and equipment service performance obligations are satisfied evenly over time as the customer simultaneously receives and consumes the benefits of the Company’s performance for these services throughout the service period. The Company allocates the transaction price to each performance obligation identified in the contract based on the relative standalone selling price (“SSP”). The Company determines SSP for the purposes of allocating the transaction price to each performance obligation based on the adjusted market assessment approach that maximizes the use of observable inputs, which includes, but is not limited to, transactions where the specific performance obligations are sold separately, list prices and offers to customers. The Company’s contracts with customers generally have an expected duration of one year or less, and therefore the Company has elected the practical expedient in ASC 606 to not disclose information about its remaining performance obligations. Any incremental costs to obtain contracts are recorded as selling, general and administrative expense as incurred due to the short duration of the Company’s contracts. The Company’s contract balances consisted solely of accounts receivable as of December 31, 2020 and 2019. In May 2020, the Company entered into bi-lateral distribution agreements with Biotronik SE & Co. KG (“Biotronik”) (the “Bi-Lateral Distribution Agreements”). Pursuant to the Bi-Lateral Distribution Agreements, the Company obtained a non-exclusive license to distribute a range of Biotronik’s products and accessories in the United States, Canada, China, Hong Kong and multiple Western European countries under the Company’s private label. Moreover, if an investigational device exemption (“IDE”) clinical trial is required for these products to obtain regulatory approval in the United States, or a clinical trial is required for these products to obtain regulatory approval in China, the Company will obtain an exclusive distribution right in such territories for a term of up to five years commencing on the date of regulatory approval if the Company covers the cost of the IDE or other clinical trial and the Company conducts such study within a specified period. Biotronik also agreed to distribute the Company’s products and accessories in Germany, Japan, Mexico, Switzerland and multiple countries in Asia-Pacific, Eastern Europe, the Middle East and South America. The Company also granted Biotronik a co-exclusive right to distribute these products in Hong Kong. Each party will pay to the other party specified transfer prices on the sale of the other party’s products and, accordingly, will earn a distribution margin on the sale of the other party’s products. The following table provides revenue by geographic location for the years ended December 31, 2020 and 2019 (in thousands): Year Ended December 31, 2020 2019 Acutus Direct United States $ 4,625 $ 738 Europe 2,347 2,045 Total Acutus direct revenue 6,972 2,783 Distribution Agreements United States 229 — Europe 1,263 53 Total revenue through distribution 1,492 53 Total revenue $ 8,464 $ 2,836 Inventory Inventory is comprised of raw materials, direct labor and manufacturing overhead and is stated at the lower of cost (first-in, first-out basis) or net realizable value. The Company recorded write-downs for excess and obsolete inventory based on management’s review of inventories on hand, compared to estimated future usage and sales, shelf-life and assumptions about the likelihood of obsolescence of $0.1 million and $0.7 million, for the years ended December 31, 2020 and 2019, respectively. Accounts Receivable Trade accounts receivable are recorded net of allowances for uncollectible accounts. The Company evaluates the collectability of its accounts receivable based on various factors including historical experience, the length of time the receivables are past due and the financial health of the customer. The Company reserves specific receivables if collectability is no longer reasonably assured. Based upon the assessment of these factors, the Company did not record an allowance for uncollectible accounts as of December 31, 2020 or 2019. Property and Equipment, Net Property and equipment are recorded at cost. Depreciation and amortization are provided using the straight-line method over the estimated useful lives of the related assets, generally three to five years, or, in the case of leasehold improvements, over the lesser of the useful life of the related asset or the lease term. Intangible Assets Intangible assets consist of acquired developed technology, acquired in-process technology, trademarks and trade names and a customer-related intangible which were acquired as part of the acquisition of Rhythm Xience, Inc. (“Rhythm Xience”) in June 2019. The Company determines the appropriate useful life of its finite-lived intangible assets by performing an analysis of expected cash flows of the acquired assets. Finite-lived intangible assets are amortized over their estimated useful lives using the straight-line method, which approximates the pattern in which the economic benefits are consumed. Acquired in-process technology was classified as an indefinite-lived intangible asset, until the receipt of U.S. Food and Drug Administration (“FDA”) approval for the technology in January 2020. Once the FDA approval was received, the in-process technology was classified as a finite-lived intangible and amortization for in-process technology began. Indefinite-lived intangible assets are tested for impairment at least annually and are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Indefinite-lived intangible assets are impaired if their estimated fair values are less than their carrying value. Goodwill Goodwill represents the excess of the purchase price of an entity over the estimated fair value of the assets acquired and liabilities assumed, and it is presented as goodwill in the accompanying consolidated balance sheets. Under ASC 350, Intangibles – Goodwill and Other Impairment of Long-Lived Assets The Company reviews long-lived assets, including property and equipment and finite-lived intangible assets, for impairment whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. An impairment loss is recognized when the asset’s carrying value exceeds the total undiscounted cash flows expected from its use and eventual disposition. The amount of the impairment loss is determined as the excess of the carrying value of the asset over its fair value. For the year ended December 31, 2019, the Company recorded a $0.8 million impairment of its property and equipment resulting from the release of a second generation of the Company’s AcQMap System. For the year ended December 31, 2020, the Company determined that there was no impairment of property and equipment. For the years ended December 31, 2020 and 2019, the Company did not have an impairment of the intangible assets. Foreign Currency Translation and Transactions The assets, liabilities and results of operations of Acutus NV are measured using their functional currency, the Euro, which is the currency of the primary foreign economic environment in which this subsidiary operates. Upon consolidating this entity with the Company, its assets and liabilities are translated to U.S. dollars at currency exchange rates as of the balance sheet date and its revenues and expenses are translated at the weighted-average currency exchange rates during the applicable reporting periods. Translation adjustments resulting from the process of translating this entity’s financial statements are reported in accumulated other comprehensive income (loss) in the consolidated balance sheets and foreign currency translation adjustment in the consolidated statements of operations and comprehensive loss. Lessee Leases The Company accounts for its leases under ASC 842, Leases In calculating the right-of-use asset and lease liability, the Company elects to combine lease and non-lease components. The Company excludes short-term leases having initial terms of 12 months or less from the new guidance as an accounting policy election. Cost of Products Sold Cost of products sold includes raw materials, direct labor, manufacturing overhead, shipping and receiving costs and other less significant indirect costs related to the production of the Company’s products. Research and Development The Company is actively engaged in new product research and development efforts. Research and development expenses consist primarily of salaries and employee-related costs (including stock-based compensation) for personnel directly engaged in research and development activities, clinical trial expenses, equipment costs, material costs, allocated rent and facilities costs and depreciation. Research and development expenses also include payments for the asset acquisition from Biotronik and VascoMed GmbH (collectively, the “Biotronik Parties”) for certain licenses of patents, technology, know-how rights and equipment (the “Biotronik Asset Acquisition”). Research and development expenses relating to possible future products are expensed as incurred. The Company also accrues and expenses costs for activities associated with clinical trials performed by third parties as incurred. All other costs relative to setting up clinical trial sites are expensed as incurred. Clinical trial site costs related to patient enrollment are accrued as patients are entered into the trials. Selling, General and Administrative Selling, general and administrative (“SG&A”) expenses consist primarily of salaries and employee-related costs (including stock-based compensation) for personnel in sales, executive, finance and other administrative functions, allocated rent and facilities costs, legal fees relating to intellectual property and corporate matters, professional fees for accounting and consulting services, marketing costs and insurance costs. The Company expenses all SG&A costs as incurred. Fair Value Measurements Fair value measurements are based on the premise that fair value is an exit price representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the following three-tier fair value hierarchy has been used in determining the inputs used in measuring fair value: Level 1—Quoted prices in active markets for identical assets or liabilities. Level 2—Observable inputs other than Level 1 prices for similar assets or liabilities that are directly or indirectly observable in the marketplace. Level 3—Unobservable inputs which are supported by little or no market activity and that are financial instruments whose values are determined using pricing models, discounted cash flow methodologies or similar techniques, as well as instruments for which the determination of fair value requires significant judgment or estimation. Financial instruments measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Management’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. The use of different assumptions and/or estimation methodologies may have a material effect on estimated fair values. Accordingly, the fair value estimates disclosed or initial amounts recorded may not be indicative of the amount that the Company or holders of the instruments could realize in a current market exchange. There were no transfers made among the three levels in the fair value hierarchy for the years ended December 31, 2020 and 2019. As of December 31, 2020 and 2019, the Company’s cash (excluding cash equivalents which are recorded at fair value on a recurring basis), restricted cash, accounts receivable, accounts payable and accrued expenses were carried at cost, which approximates the fair values due to the short-term nature of the instruments. The carrying amount of the Company’s long-term debt approximates fair value due to its variable market interest rate and management’s opinion that current rates and terms that would be available to the Company with the same maturity and security structure would be essentially equivalent to that of the Company’s long-term debt. Certain features of the convertible notes were determined to be an embedded derivative requiring separate measurement from the loan host instrument. The following tables classify the Company’s financial assets and liabilities measured at fair value on a recurring basis into the fair value hierarchy as of December 31, 2020 and 2019 (in thousands): Fair Value Measured as of December 31, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fair Value at December 31, 2020 Assets included in: Cash and cash equivalents Money market securities $ 19,070 $ — $ — $ 19,070 Marketable securities at fair value Corporate debt securities — 31,353 — 31,353 U.S. treasury securities — 20,531 — 20,531 Commercial paper — 53,955 — 53,955 Asset-backed securities — 8,726 — 8,726 Total fair value $ 19,070 $ 114,565 $ — $ 133,635 Liabilities included in: Contingent consideration $ — $ — $ 9,300 $ 9,300 Total fair value $ — $ — $ 9,300 $ 9,300 Fair Value Measured as of December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fair Value at December 31, 2019 Assets included in: Cash and cash equivalents Money market securities $ 8,901 $ — $ — $ 8,901 Marketable securities at fair value Corporate debt securities — 28,224 — 28,224 Asset-backed securities — 17,121 — 17,121 U.S. treasury securities — 5,032 — 5,032 Commercial paper — 11,974 — 11,974 Total fair value $ 8,901 $ 62,351 $ — $ 71,252 Liabilities included in: Contingent consideration $ — $ — $ 13,900 $ 13,900 Common and preferred stock warrant liability — — 8,919 8,919 Total fair value $ — $ — $ 22,819 $ 22,819 The fair value of the Company’s money market funds is determined using quoted market prices in active markets for identical assets. The Company’s portfolio of marketable securities is comprised of commercial paper, asset-backed securities, U.S. treasury securities and short-term highly liquid, high credit quality corporate debt securities. The fair value for the available-for-sale marketable securities is determined based on trade prices in active markets for identical assets (Level 1 inputs) or valuation models using inputs that are observable either directly or indirectly (Level 2 inputs), such as quoted prices for similar assets, yield curve, volatility factors, credit spreads, default rates, loss severity, current market and contractual prices for the underlying instruments, broker and dealer quotes, as well as other relevant economic measures. The following table presents changes in Level 3 liabilities measured at fair value for the years ended December 31, 2020 and 2019 (in thousands): Common and Preferred Stock Warrant Liability Contingent Consideration Embedded Derivative in 2018 Convertible Notes Total Balance, December 31, 2018 $ 6,842 $ — $ 5,568 $ 12,410 Issuance of preferred stock warrants in conjunction with debt 872 — — 872 Conversion of convertible notes — — (6,282 ) (6,282 ) Fair value of contingent consideration - Rhythm Xience acquisition — 13,400 — 13,400 Change in fair value 1,205 500 714 2,419 Balance, December 31, 2019 $ 8,919 $ 13,900 $ — $ 22,819 Payment of contingent consideration — (2,500 ) — (2,500 ) Issuance of preferred stock for contingent consideration — (2,197 ) — (2,197 ) Reclassification of warrant liability to stockholders' equity (14,474 ) — — (14,474 ) Change in fair value 5,555 97 — 5,652 Balance, December 31, 2020 $ — $ 9,300 $ — $ 9,300 Unrealized gains and losses associated with liabilities within the Level 3 category include changes in fair value that were attributable to both observable (e.g., changes in market interest rates) and unobservable (e.g., changes in unobservable long-dated volatilities) inputs. In June 2019, the convertible notes were converted into shares of the Company’s Series D convertible preferred stock. The fair value of the common stock and preferred stock warrant liability was estimated using a Monte Carlo simulation in the first quarter of 2019 and as an output of the Hybrid Method for the remaining quarters of 2019 and the first and second quarter of 2020. The underlying equity included in the Monte Carlo simulation and the Hybrid Method was determined based on the equity value implied from the preferred stock transactions and from examination of income and market approaches for measurement dates in which a preferred transaction was not applicable. Additionally, the expected IPO value was considered in the determination of the equity value. The fair value of the warrants was impacted by the model selected as well as assumptions surrounding unobservable inputs including the underlying equity value, risk-free interest rate, expected dividend yield, contractual term and expected volatility. On August 10, 2020 when the warrants were converted and became equity classified warrants, the fair value of the common and preferred stock warrant liability was estimated using a Black-Scholes model. The underlying equity included in the Black-Scholes model was based on the IPO share price of $18.00. August 10, December 31, 2020 2019 Risk-free interest rate 0.39% 1.59% - 1.60% Expected dividend yield — — Contractual term in years 7.8 - 8.8 0.7 - 1.0 Expected volatility 65.0% 60.0% - 110.5% The fair value of the contingent consideration from the acquisition of Rhythm Xience represents the estimated fair value of future payments due to the sellers of Rhythm Xience based on the achievement of certain milestones and revenue-based targets in certain years. The initial fair value of the revenue-based contingent consideration was calculated through the use of a Monte Carlo simulation using revenue projections for the respective earn-out period, corresponding targets and approximate timing of payments as outlined in the purchase agreement. The analyses used the following assumptions: (i) expected term; (ii) risk-adjusted net sales or earnings; (iii) risk-free interest rate; and (iv) expected volatility of earnings. Estimated payments, as determined through the respective model, were further discounted by a credit spread assumption to account for credit risk. The fair value of the milestones-based contingent consideration was determined by probability weighting and discounting to the respective valuation date at the Company’s cost of debt. The Company’s cost of debt was determined by performing a synthetic credit rating for the Company and selecting yields based on companies with a similar credit rating. The contingent consideration is revalued to fair value each period, and any increase or decrease is recorded in operating loss. The fair value of the contingent consideration may be impacted by certain unobservable inputs, most significantly with regard to discount rates, expected volatility and historical and projected performance. Significant changes to these inputs in isolation could result in a significantly different fair value measurement. The weighted-average (in aggregate) significant unobservable inputs (Level 3 inputs) used in measuring the contingent consideration from the acquisition of Rhythm Xience as of December 31, 2020, December 31, 2019 and June 18, 2019 (acquisition date) were as follows: December 31, 2020 December 31, 2019 June 18, 2019 (Acquisition Date) Risk-free interest rate 0.20% 1.60% 1.80% Expected term in years 1.0 - 2.0 1.0 - 2.0 1.0 - 2.0 Expected volatility 17.2% 11.8% 11.6% As of June 12, 2019 (conversion date), the fair value of the embedded derivative of $6.3 million was based on the difference between the fair value of the Series D convertible preferred stock issued upon the conversion of the 2018 Convertible Notes, as defined below, of $31.4 million, or $16.67 per share, and the discounted conversion price of $25.1 million, or $13.33 per share. Stock-Based Compensation The Company accounts for all stock-based payments to employees and non-employees, including grants of stock options, restricted stock awards (“RSAs”), restricted stock units (“RSUs”) and restricted stock units with non-market performance and service conditions (“PSUs”) to be recognized in the consolidated financial statements, based on their respective grant date fair values. The Company estimates the fair value of stock option grants using the Black-Scholes option pricing model. The RSAs, RSUs and PSUs are valued based on the fair value of the Company’s common stock on the date of grant. The assumptions used in calculating the fair value of stock-based awards represent management’s best estimates and involve inherent uncertainties and the application of management’s judgment. The Company expenses stock-based compensation related to stock options, RSAs and RSUs over the requisite service period. As the PSUs have a performance condition, compensation expense was recognized for each vesting tranche over the respective requisite service period of each tranche upon the IPO closing on August 10, 2020, when the Company’s management deemed it probable that the performance conditions were satisfied. The Company recognized a cumulative true-up adjustment related to PSUs once the conditions became probable of being satisfied as the related service period had been completed in a prior period. All stock-based compensation costs are recorded in cost of products sold, research and development expense or SG&A expense in the consolidated statements of operations and comprehensive loss based upon the respective employee’s or non-employee’s roles within the Company. Forfeitures are recorded as they occur. See also “ Note 16—Stock-Based Compensation Income Taxes Income taxes are recorded in accordance with ASC 740, Income Taxes The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the

Asset Acquisition and Business

Asset Acquisition and Business Combination	12 Months Ended
Asset Acquisition and Business Combination	Dec. 31, 2020
Business Combination Recognized Identifiable Assets Acquired Goodwill And Liabilities Assumed Net [Abstract]
Asset Acquisition and Business Combination	Note 3—Asset Acquisition and Business Combination Biotronik Asset Acquisition In July 2019, the Company entered into a License and Distribution Agreement with the Biotronik Parties to obtain certain licenses to the Biotronik Parties’ patents, whereby the Company acquired certain manufacturing equipment and obtained from the Biotronik Parties a license under certain patents and technology to develop, commercialize, distribute and manufacture the AcQBlate Force ablation catheters and Qubic Force device. In exchange for the rights granted to the Company, the Company made cash payments totaling $10.0 million during the year ended December 31, 2019, and issued 273,070 shares of Series D convertible preferred stock with an implied value of $5.0 million during the year ended December 31, 2020. The implied value of $5.0 million was recorded as an accrued liability as of December 31, 2019. In accordance with ASC 805, the Biotronik Asset Acquisition is accounted for as an asset acquisition as substantially all of the $15.0 million value transferred to Biotronik was allocated to intellectual property. On the acquisition date, the products licensed had not yet received regulatory approval and the intellectual property did not have an alternative use. Accordingly, the $15.0 million paid to Biotronik was immediately charged to research and development expense - licensed acquired in the consolidated statement of operations and comprehensive loss in July 2019. Additional contingent milestone payments of up to $10.0 million, of which $2.0 million has been accrued as of December 31, 2020, are to be made to the Biotronik Parties contingent upon certain regulatory approvals and first commercial sale. In further consideration of the rights granted, beginning with the Company’s first commercial sale of the first force sensing ablation catheter within the licensed product line, the Company will also make per unit royalty payments. The Company determined that the remaining $8.0 million contingent milestone and royalty payments are not probable and estimable and therefore have not been recorded as a liability as of December 31, 2020. All $10.0 million of the contingent milestone and royalty payments were not probable and estimable and therefore were not recorded as a liability as of December 31, 2019. Upon regulatory approval in December 2020 of the Company’s force sensing ablation catheter in Europe, the $2.0 million milestone was capitalized and will be amortized, and the royalty payments are recorded as cost of products sold as sales of catheters are recognized. Rhythm Xience Business Combination On June 18, 2019 (the “Acquisition Date”), the Company acquired an integrated family of transseptal crossing and steerable introducer systems through its acquisition of Rhythm Xience for $3.0 million in cash in exchange for all of the stock of Rhythm Xience (the “Rhythm Xience Acquisition”). The cash payment did not include the potential $17.0 million in earn out consideration, of which $2.2 million was paid with the issuance of Series D convertible preferred stock in February 2020 and the remainder is to be paid based on the achievement of certain regulatory milestones and revenue milestones. In accordance with ASC 805, the Rhythm Xience Acquisition was accounted for as a business combination. Purchase Price Allocation The following table summarizes the allocation of the purchase price to the assets acquired and liabilities assumed for the Rhythm Xience Acquisition (in thousands): Accounts receivable, net $ 3 Prepaid expenses and other current assets 8 Property and equipment, net 3 Intangible assets 4,360 Goodwill 12,026 Contingent consideration (13,400 ) Cash consideration $ 3,000 The Company recorded $12.0 million of goodwill that arose out of synergies from the Rhythm Xience Acquisition. The Company does not expect goodwill to be deductible for tax purposes. As part of Rhythm Xience Acquisition, the Company recorded a contingent consideration liability for potential additional payments due to the sellers of Rhythm Xience if certain regulatory approval milestones and revenue milestones are achieved. The initial contingent consideration liability of $13.4 million was based on the fair value of the contingent consideration liability at the Acquisition Date. During the year ended December 31, 2020, the Company issued 119,993 shares of Series D convertible preferred stock and paid $2.5 million of the contingent consideration for the achievement of certain regulatory milestones and revenue milestones. Additionally, the Company recorded a $0.1 million increase and a $0.5 million increase to the fair value of the contingent consideration liability for the year ended December 31, 2020 and the period from June 18, 2019 to December 31, 2019, respectively, which is included in change in fair value of contingent consideration in the consolidated statements of operations and comprehensive loss for the years ended December 31, 2020 and 2019, respectively. As of December 31, 2020, the contingent consideration liability of $9.3 million is the fair value of the remaining payments due to the sellers of Rhythm Xience if certain additional regulatory approval milestones and revenue milestones are achieved. From the Acquisition Date to December 31, 2019, the Company recorded revenue and net loss for Rhythm Xience of $0.1 million and $1.0 million, respectively. Pro Forma (Unaudited) The following unaudited pro forma financial information presents results of operations as if the Rhythm Xience Acquisition had occurred on January 1, 2019 (in thousands): Year Ended December 31, 2019 Revenue $ 2,933 Net loss $ (97,850 ) For purposes of the pro forma disclosures above, the primary adjustments for the year ended December 31, 2019 include the elimination of transaction costs of $0.2 million, the income tax benefit of Rhythm Xience of $0.1 million and interest expense of $0.1 million, and the inclusion of amortization of the intangible assets of $0.2 million. For the year ended December 31, 2019, the Company recorded acquisition costs of $0.2 million for the Rhythm Xience Acquisition, which are recorded in SG&A expense in the consolidated statement of operations and comprehensive loss.

Marketable Securities

Marketable Securities	12 Months Ended
Marketable Securities	Dec. 31, 2020
Investments Debt And Equity Securities [Abstract]
Marketable Securities	Note 4—Marketable Securities Marketable securities consisted of the following as of December 31, 2020 and 2019 (in thousands): December 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Available-for-sale securities - short-term: Corporate debt securities $ 31,359 $ — $ (6 ) $ 31,353 U.S. treasury securities 20,533 — (2 ) 20,531 Commercial paper 53,955 — — 53,955 Total available-for-sale securities - short-term 105,847 — (8 ) 105,839 Asset-backed securities, long-term 8,726 — 8,726 Total available-for-sale securities $ 114,573 $ — $ (8 ) $ 114,565 December 31, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Available-for-sale securities - short-term: Corporate debt securities $ 28,204 $ 20 $ — $ 28,224 Asset-backed securities 17,108 13 — 17,121 U.S. treasury securities 5,020 12 — 5,032 Commercial paper 11,974 — — 11,974 Total available-for-sale securities $ 62,306 $ 45 $ — $ 62,351 As of December 31, 2020, the Company’s available-for-sale securities classified as short-term of $105.8 million mature in one year or less and the available-for-sale securities classified as long-term of $8.7 million mature within two years. As of December 31, 2019, all of the Company’s available-for-sale securities mature in one year or less.

Inventory

Inventory	12 Months Ended
Inventory	Dec. 31, 2020
Inventory Disclosure [Abstract]
Inventory	Note 5—Inventory Inventory as of December 31, 2020 and 2019 consisted of the following (in thousands): December 31, December 31, 2020 2019 Raw materials $ 7,960 $ 5,492 Work in process 1,267 1,605 Finished goods 3,731 1,327 Total inventory $ 12,958 $ 8,424

Lessor Sales-Type Leases

Lessor Sales-Type Leases	12 Months Ended
Lessor Sales-Type Leases	Dec. 31, 2020
Leases [Abstract]
Lessor Sales-Type Leases	Note 6—Lessor Sales-Type Leases The Company recognizes revenue and costs, as well as a lease receivable, at the time embedded sales-type leases within its deferred equipment agreements commence. Lease revenue related to sales-type leases for the year ended December 31, 2020 was $0.8 million and is included within revenue in the consolidated statements of operations and comprehensive loss. There was no lease revenue for the year ended December 31, 2019. Costs related to embedded leases within the Company’s deferred equipment agreements are included in cost of products sold in the consolidated statements of operations and comprehensive loss. The Company has a short-term lease receivable of $0.4 million and a long-term lease receivable of $0.4 million included in prepaid expenses and other current assets and other assets, respectively, as of December 31, 2020. There was no lease receivable as of December 31, 2019. As of December 31, 2020, estimated future maturities of customer sales-type lease receivables for each of the following years were as follows (in thousands): Year ending December 31, 2021 $ 367 Year ending December 31, 2022 338 Year ending December 31, 2023 107 Year ending December 31, 2024 27 Year ending December 31, 2025 - Lease receivable $ 839

Property and Equipment, Net

Property and Equipment, Net	12 Months Ended
Property and Equipment, Net	Dec. 31, 2020
Property Plant And Equipment [Abstract]
Property and Equipment, Net	Note 7—Property and Equipment, Net The Company’s property and equipment, net, consisted of the following as of December 31, 2020 and 2019 (in thousands): December 31, December 31, 2020 2019 Medical diagnostic equipment $ 13,242 $ 5,492 Furniture and fixtures 388 159 Office equipment 1,392 1,321 Laboratory equipment and software 3,491 2,807 Leasehold improvements 608 507 Construction in process 468 306 Total property and equipment 19,589 10,592 Less: accumulated depreciation (7,233 ) (6,165 ) Property and equipment, net $ 12,356 $ 4,427 Property and equipment includes certain medical diagnostic equipment, AcQMap Systems, located at customer premises. The Company retains ownership of the equipment and has the right to remove the equipment if it is not being used according to expectations. The Company expenses the cost of the equipment when it is subsequently sold or enters into a sales-type lease agreement. See also “ Note 6—Lessor Sales-Type Leases Depreciation expense was $2.8 million and $2.3 million for the years ended December 31, 2020 and 2019, respectively. For the year ended December 31, 2019, the Company recorded a $0.8 million impairment of its property and equipment. For the year ended December 31, 2020, the Company determined that there was no impairment of property and equipment.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
Goodwill and Intangible Assets	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Note 8—Goodwill and Intangible Assets The tables below summarize goodwill and intangible assets activities as of December 31, 2020 and 2019 (in thousands): Goodwill Intangible Assets Balance, December 31, 2018 $ — $ — Rhythm Xience Acquisition 12,026 4,360 Amortization expense — (250 ) Balance, December 31, 2019 12,026 4,110 Biotronik License Agreement — 2,000 Amortization expense — (457 ) Balance, December 31, 2020 $ 12,026 $ 5,653 Estimated Useful Weighted Average Remaining Life (in years) Life (in years) Intangible Assets Accumulated Amortization December 31, 2020 Developed technology 10 8.6 $ 4,200 $ (600 ) $ 3,600 Customer-related intangible 5 3.5 100 (30 ) 70 Licensed intangibles 10 9.9 2,000 (17 ) 1,983 Total $ 6,300 $ (647 ) $ 5,653 Estimated Useful Weighted Average Remaining Life (in years) Life (in years) Intangible Assets Accumulated Amortization December 31, 2019 Developed technology 10 9.5 $ 3,600 $ (180 ) $ 3,420 In-process technology indefinite 600 — 600 Trademarks and trade names 0.5 — 60 (60 ) — Customer-related intangible 5 4.5 100 (10 ) 90 Total $ 4,360 $ (250 ) $ 4,110 Acquired in-process technology was classified as an indefinite-lived intangible asset until the receipt of FDA approval for the technology in January 2020. Once FDA approval was received, the in-process technology was reclassified as developed technology and amortization began. The Company recorded amortization expense related to the above intangible assets of $0.5 million and $0.3 million for the years ended December 31, 2020 and 2019, respectively. The following table shows the remaining amortization expense associated with amortizable intangible assets as of December 31, 2020 (in thousands): Developed Technology Customer- Related Intangible Licensed Intangibles Total Amortization Year ending December 31, 2021 $ 420 $ 20 $ 200 $ 640 Year ending December 31, 2022 420 20 200 640 Year ending December 31, 2023 420 20 200 640 Year ending December 31, 2024 420 10 200 630 Year ending December 31, 2025 420 — 200 620 Thereafter 1,500 — 983 2,483 Total $ 3,600 $ 70 $ 1,983 $ 5,653

Accrued Liabilities

Accrued Liabilities	12 Months Ended
Accrued Liabilities	Dec. 31, 2020
Payables And Accruals [Abstract]
Accrued Liabilities	Note 9—Accrued Liabilities Accrued liabilities consisted of the following as of December 31, 2020 and 2019 (in thousands): December 31, December 31, 2020 2019 Compensation and related expenses $ 6,250 $ 3,785 Professional fees 120 188 Deferred revenue 301 311 Sales and use tax 169 151 Biotronik Asset Acquisition - accrued purchase price — 5,000 Other 468 641 Total accrued liabilities $ 7,308 $ 10,076

Debt

Debt	12 Months Ended
Debt	Dec. 31, 2020
Debt Disclosure [Abstract]
Debt	Note 10—Debt Outstanding debt as of December 31, 2020 and 2019 consisted of the following (in thousands): December 31, December 31, 2020 2019 2019 Credit Agreement (1) $ 44,550 $ 44,550 Total debt, gross 44,550 44,550 Less: Unamortized debt discount and fees (5,539 ) (6,306 ) Total long-term debt $ 39,011 $ 38,244 (1) The 2019 Credit Agreement includes final payment fees of $4.6 million. 2019 Credit Agreement On May 20, 2019, the Company entered into a Credit Agreement (the “2019 Credit Agreement”). The 2019 Credit Agreement provided the Company with a senior term loan facility in aggregate principal amount of $70.0 million, of which the Company borrowed $40.0 million upon closing. Of the remaining $30.0 million, none is available for borrowing. The 2019 Credit Agreement bears interest per annum at 7.75% plus LIBOR for such interest period and the principal amount of term loans outstanding under the 2019 Credit Agreement is due on May 20, 2024. The 2019 Credit Agreement provides for final payment fees of an additional $4.6 million that are due upon prepayment or on the maturity date or upon acceleration. Upon the occurrence and during an event of default, which includes but is not limited to payment default, covenant default or the occurrence of a material adverse change, the lenders may declare all outstanding principal and accrued and unpaid interest immediately due and payable, all unfunded commitments would be terminated, there would be an increase in the applicable interest rate by 10% per annum, and the lenders would be entitled to exercise their other rights and remedies provided for under the 2019 Credit Agreement. Additionally, the lenders may request repayment of a portion of obligations outstanding under the 2019 Credit Agreement to the extent of the Company’s receipt of any (i) net casualty proceeds or (ii) net asset sales proceeds, as defined. These acceleration and early payment features are an embedded derivative that is separately measured from the loan host instrument and classified with the loan host instrument. In connection with the issuance of the 2019 Credit Agreement, the Company issued liability-classified warrants with a fair value of $0.9 million to purchase 419,992 shares of Series C convertible preferred stock at $16.67 per share. These warrants were subsequently automatically converted into warrants to purchase an equal number of shares of the Company’s Series D convertible preferred stock at $16.67 per share and then were automatically converted into warrants to purchase an equal number of shares of common stock at $16.67 per share. The initial recognition of the warrant liability and direct fees of $1.2 million and final payment fees of $4.6 million for the 2019 Credit Agreement resulted in a discount of $6.7 million, which is being amortized to interest expense over the term of the 2019 Credit Agreement using the effective interest method. The Company’s obligations under the 2019 Credit Agreement are secured by substantially all of its assets, including its intellectual property, and is guaranteed by Acutus NV. The 2019 Credit Agreement contains customary affirmative and negative covenants, including with respect to the Company’s ability to enter into fundamental transactions, incur additional indebtedness, grant liens, pay any dividend or make any distributions to its holders, make investments and merge or consolidate with any other person or engage in transactions with its affiliates, but does not include any financial covenants, other than a minimum liquidity requirement. As of and for the years ended December 31, 2020 and 2019, the Company was in compliance with all such covenants. 2019 Convertible Notes On May 20, 2019, the Company sold and issued $37.0 million in aggregate principal amount of convertible promissory notes (the “2019 Convertible Notes”). The 2019 Convertible Notes bore interest at 13% per annum and were due on December 31, 2019. The 2019 Convertible Notes, including accrued interest, automatically converted into preferred stock at the lowest price per share paid by a cash investor in a qualified equity financing of at least $23.0 million (excluding the principal of any debt that is cancelled or converted into preferred stock in the equity financing), which occurred on June 12, 2019 (see “—Conversion of Convertible Notes” Distinguishing Liabilities from Equity 2018 Term Loan On July 31, 2018, the Company entered into a loan and security agreement with investors for a $15.0 million secured term loan credit facility, with an interest rate of the greater of: (i) 8.95% and (ii) 7.04% plus the 30-day month-end U.S. LIBOR rate maturing on July 1, 2023 (the “2018 Term Loan”). The 2018 Term Loan provided for a final payment fee of an additional $0.6 million (the “Final Fee”) due upon prepayment or on the maturity date, and prepayment penalties. Interest was payable on a monthly basis. Upon the occurrence and during an event of default, which included but was not limited to payment default, covenant default or the occurrence of a material adverse change, the lenders could declare all outstanding principal and accrued and unpaid interest immediately due and payable, all unfunded commitments would be terminated, there would be an increase in the applicable interest rate by 5.0% per annum, and the lenders would be entitled to exercise their other rights and remedies provided for under the 2018 Term Loan. The Company’s obligations under the 2018 Term Loan were secured by substantially all of its assets, excluding intellectual property, and subject to certain exceptions and limitations. The 2018 Term Loan contained customary covenants. Until repayment in May 2019, the Company was in compliance with all such covenants. In connection with the entry into the 2018 Term Loan, the Company issued liability-classified warrants with a fair value of $0.3 million to purchase 26,998 shares of Series C convertible preferred stock at $16.67 per share. These warrants were subsequently automatically converted into warrants to purchase an equal number of shares of the Company’s Series D convertible preferred stock at $16.67 per share and then were automatically converted into warrants to purchase an equal number of shares of common stock at $16.67 per share. The initial recognition of the warrant liability, the Final Fee and direct fees of $0.1 million for the 2018 Term Loan resulted in a discount of $1.1 million, which was being amortized to interest expense over the term of the 2018 Term Loan using the effective interest method. In May 2019, in connection with the entry into the 2019 Credit Agreement, the Company paid $16.2 million for the extinguishment of the 2018 Term Loan, including the principal and accrued interest, the Final Fee and a prepayment penalty. The Company recorded a loss on extinguishment of debt of $1.4 million related to the write-off of deferred financing fees of $0.9 million, the prepayment penalty of $0.5 million and fees of approximately $0.1 million. 2018 Convertible Notes On June 7, 2018, the Company sold and issued convertible notes payable to certain of the Company’s investors for total proceeds of $22.8 million (the “2018 Convertible Notes”). The 2018 Convertible Notes bore interest at 10.0% per annum and were originally due on June 7, 2019, but were converted to Series D convertible preferred stock on June 12, 2019. In connection with issuance of the 2018 Convertible Notes, the Company issued liability-classified warrants with a fair value of $5.4 million to purchase 501,946 shares of common stock. In accordance with ASC 470-20, Debt with Conversions and Other Options, The 2018 Convertible Notes, including accrued interest, would automatically convert into preferred stock at 80.0% of the lowest price per share paid by a cash investor in an equity financing of at least $20.0 million (excluding the principal of any debt that is cancelled or converted into preferred stock in the equity financing) (the “Automatic Conversion Feature”). In accordance with ASC 815-15, Embedded Derivatives The Company recorded a loss on the issuance of the 2018 Convertible Notes and warrants of $0.9 million for the excess fair value of the Automatic Conversion Feature after allocating the gross proceeds of the 2018 Convertible Notes to the initial fair value of the warrants and the BCF by lender. The initial recognition of the warrant liability, the BCF and the Automatic Conversion Feature (excluding the loss on the issuance of convertible notes and warrants) resulted in a discount of $20.3 million on the 2018 Convertible Notes, which was amortized to interest expense over the term of the 2018 Convertible Notes using the effective interest method. In June 2019, the 2018 Convertible Notes were converted to Series D convertible preferred stock in accordance with the Automatic Conversion Feature. See “—Conversion of Convertible Notes” Conversion of Convertible Notes In June 2019, in conjunction with the Series D preferred stock issuance, the 2019 Convertible Notes and the 2018 Convertible Notes, along with accrued interest thereon, were converted into shares of Series D convertible preferred stock. As such, the convertible noteholders received an aggregate of 4,108,478 shares of Series D convertible preferred stock for the conversion of all outstanding 2019 Convertible Notes and 2018 Convertible Notes at a conversion price of $$16.67 per share and $13.33 per share (including the 20.0% discount provided for in the 2018 Convertible Notes), respectively. The following table provides the shares issued upon conversion: Conversion on June 12, 2019 Stated Interest Rate Conversion Price Conversion Price per Share Face Value (in thousands) Accrued Interest (in thousands) Total Conversion Amount (in thousands) Shares Issued 2019 Convertible Notes 13% Lowest price paid by cash investor in 2019 Series D preferred stock issuance $ 16.67 $ 37,000 $ 66 $ 37,066 2,223,913 2018 Convertible Notes 10% 80% of lowest price paid by cash investor in 2019 Series D preferred stock issuance $ 13.33 22,815 2,313 25,128 1,884,565 80% of lowest price paid by cash investor in 2019 Series D preferred stock issuance $ 59,815 $ 2,379 $ 62,194 4,108,478 Upon the conversion of the 2018 Convertible Notes, the embedded derivative included in the 2018 Convertible Notes with a fair value of $6.3 million has been included in Series D convertible preferred stock in the accompanying consolidated balance sheet.

Operating Leases

Operating Leases	12 Months Ended
Operating Leases	Dec. 31, 2020
Leases [Abstract]
Operating Leases	Note 11—Operating Leases The Company leases approximately 50,800 square feet of office space for its corporate headquarters and manufacturing facility in Carlsbad, California under a noncancelable operating lease that expires on December 31, 2022. The lease is subject to variable charges for common area maintenance and other costs that are determined annually based on actual costs. The base rent is subject to an annual increase each year. The Company has a renewal option for an additional five-year term upon the expiration date of the lease, which has been excluded from the calculation of the right-of-use asset as it is not reasonably certain to be exercised. The Company also leases approximately 3,900 square feet of office space in Zaventem, Belgium under a noncancelable operating lease that expires on December 31. 2021. The lease is subject to variable charges that are determined annually for common area maintenance and other costs based on actual costs, and base rent is subject to an annual increase each year based on an index rate. The Company has a renewal option for an additional three-year term upon the expiration date of the lease, which has been included in the calculation of the right-of-use asset as it is reasonably certain to be exercised. The following table summarizes quantitative information about the Company’s operating leases for the years ended December 31, 2020 and 2019 (dollars in thousands): Year Ended December 31, 2020 2019 Operating cash flows from operating leases $ 1,013 $ 972 Right-of-use assets exchanged for operating lease liabilities $ - $ 2,978 Weighted average remaining lease term – operating leases (in years) 1.6 3.2 Weighted average discount rate – operating leases 7.0 % 7.0 % The following table provides the components of the Company’s lease cost for the years ended December 31, 2020 and 2019 (in thousands): Year Ended December 31, 2020 2019 Operating leases Operating lease cost $ 864 $ 864 Variable lease cost 311 234 Total rent expense $ 1,175 $ 1,098 As of December 31, 2020, future minimum payments under the non-cancelable operating leases were as follows (in thousands): Year ending December 31, 2021 $ 1,044 Year ending December 31, 2022 1,074 Year ending December 31, 2023 51 Year ending December 31, 2024 51 Year ending December 31, 2025 — Total 2,220 Less: present value discount (153 ) Operating lease liabilities $ 2,067

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 12—Commitments and Contingencies The Company is not a party to any material legal proceedings and is not aware of any pending or threatened claims. From time to time however, the Company may be subject to various legal proceedings and claims that arise in the ordinary course of its business activities.

Warrants

Warrants	12 Months Ended
Warrants	Dec. 31, 2020
Warrants And Rights Note Disclosure [Abstract]
Warrants	Note 13—Warrants As of December 31, 2020 and 2019, the outstanding warrants to purchase the Company’s common stock were comprised of the following: Equity Upon Exercise (After Conversion) Exercise Price Expiration Date December 31, 2020 December 31, 2019 Warrants issued in 2015 Common stock $ 5.25 1/30/25 3,808 7,616 Warrants issued with 2018 Convertible Notes Common stock $ 0.10 6/7/28 373,810 501,946 Warrants issued with 2018 Term Loan Common stock $ 16.67 7/31/28 26,998 26,998 Warrants issued with 2019 Credit Agreement Common stock $ 16.67 5/20/29 419,992 419,992 Total Warrants 824,608 956,552 The Company’s warrant activity for the years ended December 31, 2020 and 2019 is as follows: Warrants Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Balance - December 31, 2018 543,793 $ 1.10 9.3 Granted 419,992 16.67 8.5 Exercised (7,233 ) 8.29 5.1 Balance - December 31, 2019 956,552 $ 7.88 8.4 Exercised (131,944 ) 0.25 7.4 Balance - December 31, 2020 824,608 $ 9.10 7.5 Warrants Classified as Liabilities The Company’s warrants provide the holder the option to purchase a specified number of shares for a specified price. The holder may exercise the warrant in cash or exercise pursuant to a cashless exercise whereby a calculated number of shares are withheld upon exercise to satisfy the exercise price. The warrants do not provide the holder any voting rights until the warrants are exercised. Prior to the IPO, in accordance with ASC 815, other than the warrants issued in 2015, the warrants were recorded as liabilities at fair value at the issuance date. Changes in the fair value were recognized in change in fair value of warrant liability and embedded derivative in the consolidated statements of operations and comprehensive loss at the end of each reporting period. On August 10, 2020, in connection with the closing of the IPO, the warrants recorded as liabilities no longer met the definition of a derivative. Accordingly, the fair value of the common and preferred stock warrant liability of $14.5 million was reclassified to additional paid-in capital in the consolidated balance sheet Warrants Classified as Equity In accordance with ASC 815, the warrants issued in 2015 do not meet the definition of a derivative and are classified in additional paid-in capital

Convertible Preferred Stock

Convertible Preferred Stock	12 Months Ended
Convertible Preferred Stock	Dec. 31, 2020
Temporary Equity [Abstract]
Convertible Preferred Stock	Note 14—Convertible Preferred Stock On August 10, 2020, in connection with the closing of the IPO, all of the 391,210 shares of Series A, 3,088,444 shares of Series B, 4,499,921 shares of Series C and 8,593,360 shares of Series D convertible preferred stock automatically converted into an equal number of shares of common stock. There are no shares of convertible preferred stock authorized as of December 31, 2020. In February 2020, the Company issued 119,993 shares of its Series D convertible preferred stock with an implied value of $2.2 million in connection with a contingent consideration payment related to the Rhythm Xience Acquisition. In February 2020, the Company issued 273,070 shares of its Series D convertible preferred stock with an implied value of $5.0 million for the final purchase consideration of the Biotronik Asset Acquisition. As of December 31, 2019, the Company’s Amended and Restated Certificate of Incorporation authorized the issuance of 172,064,796 shares of convertible preferred stock, par value $0.001 per share, respectively, consisting of: 3,848,696 shares of Series A convertible preferred stock, 30,032,100 shares of Series B convertible preferred stock, 48,184,000 shares of Series C convertible preferred stock, 90,000,000 shares of Series D convertible preferred stock. In June and July 2019, the Company completed an equity financing pursuant to which the Company issued 8,200,297 shares of Series D convertible preferred stock in a private placement. The Series D preferred stock issuance was comprised of: (i) 4,091,819 shares at $16.67 per share for cash proceeds of $66.6 million, net of offering costs of $1.6 million; (ii) 1,884,565 shares at $13.33 per share (including a 20.0% discount) for the conversion of the outstanding 2018 Convertible Notes (and related accrued interest) of $25.1 million; and (iii) 2,223,913 shares at $16.67 per share for the conversion of the outstanding 2019 Convertible Notes (and related accrued interest) of $37.1 million. Upon the conversion of the 2018 Convertible Notes, the embedded derivative with a fair value of $6.3 million immediately prior to the conversion was included in Series D convertible preferred stock in the consolidated balance sheet. In March 2019, the Company issued 2,652 shares of Series A convertible preferred stock in exchange for 7,233 outstanding warrants in a cashless warrant exercise. Redemption The convertible preferred stock was not unconditionally redeemable at the option of the holder thereof. However, the convertible preferred stock was contingently redeemable upon certain liquidation events. As redemption by the holders was not solely within the control of the Company, all of the outstanding convertible preferred stock was classified as temporary equity in the consolidated balance sheets , prior to the conversion to common stock on August 10, 2020 Dividends The holders of shares of convertible preferred stock were entitled to receive dividends, out of any assets legally available therefore, prior and in preference to any declaration or payment of any dividend on the common stock of the Company, at the applicable dividend rate, payable on a pro rata pari passu Liquidation The holders of the Series D convertible preferred stock were entitled to receive a liquidation preference prior to any distribution to the holders of Series A convertible preferred stock, Series B convertible preferred stock and Series C convertible preferred stock (collectively the “Junior Preferred Stock”) and the holders of common stock, in the amount of the original issue price plus declared but unpaid dividends on such shares (the “Series D Liquidation Preference”). The holders of the Junior Preferred Stock were entitled to receive a liquidation preference prior to any distribution to the holders of common stock, after payment of the Series D Liquidation Preference, in the amount of the applicable original issue price plus declared but unpaid dividends on such shares. Voting Rights Holders of convertible preferred stock had the right to one vote for each share of common stock into which such preferred stock could then be converted, and with respect to such vote, such holder had full voting rights and powers equal to the voting rights and powers of the holders of common stock. As long as any shares of Series D convertible preferred stock were outstanding, the holders of such shares of Series D convertible preferred stock (voting exclusively as a separate series) were entitled to elect one director. As long as any shares of Series C convertible preferred stock were outstanding, the holders of such shares of Series C convertible preferred stock (voting exclusively as a separate series) were entitled to elect three directors. As long as any shares of Series A convertible preferred stock or Series B convertible preferred stock were outstanding, the holders of such shares (voting together as a single class and not as separate series, and on an as converted basis) were entitled to elect four directors. The holders of outstanding common stock were entitled to elect one director. The holders of convertible preferred stock and common stock (voting together as a single class and not as separate series, and on an as-converted basis) were entitled to elect any remaining directors. Conversion Each share of preferred stock was convertible, at the option of the holder thereof, at any time after the date of issuance of such share, into such number of fully paid and nonassessable shares of the Company’s common stock as was determined by dividing the original issue price, as adjusted, for such series by the applicable conversion price for such series in effect on the date the certificate is surrendered for conversion. The initial conversion price per share for each series of convertible preferred stock was the original issue price applicable to such series as follows: Series Conversion Price Series A convertible preferred stock $ 8.295 Series B convertible preferred stock $ 13.370 Series C convertible preferred stock $ 16.667 Series D convertible preferred stock $ 16.667 Each share of convertible preferred stock was automatically converted into fully-paid, non-assessable shares of common stock at the conversion rate at the time in effect for such series of preferred stock immediately upon: (i) the date, or the occurrence of an event, specified by vote or written consent or agreement of the requisite investors; or (ii) the closing of the sale of shares of common stock to the public, at a price of at least $50.00 per share, as adjusted, in a firm-commitment underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended, resulting in at least $50.0 million of net proceeds to the Company. As noted above, on August 10, 2020, all shares of Series A, Series B, Series C and Series D convertible preferred stock were converted into common stock.

Stockholders_ Equity (Deficit)

Stockholders’ Equity (Deficit)	12 Months Ended
Stockholders’ Equity (Deficit)	Dec. 31, 2020
Equity [Abstract]
Stockholders’ Equity (Deficit)	Note 15—Stockholders’ Equity (Deficit) On August 10, 2020, the Company issued 10,147,058 shares of common stock in its IPO, which included 1,323,529 shares of common stock issued upon the underwriters’ exercise in full of an option to purchase, at the public offering price less underwriting discounts and commissions, up to an additional 1,323,529 shares. The price to the public for each share was $18.00. The Company received gross proceeds of $182.6 million from the IPO. Net of underwriting discounts and commission and other offering costs, the Company received net proceeds of $166.3 million from the IPO. On August 10, 2020, in connection with the closing of the IPO, the Company filed an amended and restated certificate of incorporation (the “A&R Certificate”) with the Secretary of State of the State of Delaware. The A&R Certificate amended and restated the Company’s authorized shares of common stock to 260,000,000 and authorized shares of undesignated preferred stock to 5,000,000. As of December 31, 2019, the Company’s amended and restated certificate of incorporation authorized the issuance of 220,000,000 shares of common stock, $0.001 par value per share. Each share of common stock is entitled to one voting right. Common stock owners are entitled to dividends when funds are legally available and declared by the Board. Stock options to acquire 124,938 and 27,799 shares for the years ended December 31, 2020 and 2019, respectively, were exercised for shares of common stock. The Company received $0.6 million and $0.1 million for the years ended December 31, 2020 and 2019, respectively, for the exercise price of the stock options.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
Stock-Based Compensation	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	Note 16—Stock-Based Compensation 2020 Equity Incentive Plan The 2020 Equity Incentive Plan (“2020 Plan”), which permits the granting of non-statutory stock options, restricted stock, restricted stock units, stock appreciation rights, performance units, performance shares and other equity-based awards to employees, directors and consultants, became effective on August 5, 2020. As of December 31, 2020, 2,193,360 shares of common stock were authorized for issuance under the 2020 Plan and 1,032,016 shares remain available for issuance under the 2020 Plan. 2011 Equity Incentive Plan The Company’s 2011 Equity Incentive Plan (the “2011 Plan”) permits the granting of incentive stock options, non-statutory stock options, restricted stock, restricted stock units and other stock-based awards to employees, directors, officers and consultants. As of December 31, 2020, 2,764,600 shares of common stock were authorized for issuance under the 2011 Plan and no shares remain available for issuance under the 2011 Plan. No additional awards will be granted under the 2011 Plan. Shares that become available for issuance from the outstanding awards under the 2011 Plan due to forfeiture, or otherwise, will become available for issuance of future awards under the 2020 Plan. Stock Options The stock options generally vest over four years and have a ten-year contractual term. The fair value of each employee and non-employee stock option grant is estimated on the date of grant using the Black-Scholes option pricing model. The Company’s common stock became publicly traded in August 2020 The following assumptions were used to estimate the fair value of stock option for the years ended December 31, 2020 and 2019: Year Ended December 31, 2020 2019 Risk-free interest rate 0.35% - 0.9% 1.6% - 2.1% Expected dividend yield — — Expected term in years 7.0 6.4 - 10.0 Expected volatility 60% - 80% 80% The following table summarizes stock option activity during the years ended December 31, 2020 and 2019: Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value (in thousands) Outstanding as of December 31, 2018 1,587,410 $ 8.13 8.0 $ 6,012 Options granted 540,157 13.37 Options exercised (27,806 ) 3.87 $ 251 Options forfeited (58,556 ) 9.86 Outstanding as of December 31, 2019 2,041,205 $ 9.52 7.7 $ 10,782 Options granted 1,794,895 16.91 Options exercised (172,312 ) 7.52 $ 1,660 Options forfeited (260,181 ) 12.10 Outstanding as of December 31, 2020 3,403,607 $ 13.32 8.1 $ 52,866 Options vested and exercisable as of December 31, 2020 1,403,764 $ 9.55 6.6 $ 27,035 The aggregate intrinsic value for options outstanding in the above table represents the product of the number of options outstanding multiplied by the difference between the per share fair value of the Company’s stock on the last day of the fiscal period, which was $28.81, $14.81 and $11.91 as of December 31, 2020, 2019 and 2018, respectively, and the exercise price. The aggregate intrinsic value for options exercised in the above table represents the product of the number of options exercised multiplied by the difference between the per share fair value of the Company’s stock on the date of exercise and the exercise price. The intrinsic value amounts reflected for 2018 and 2019 have been revised from what was previously disclosed. The weighted-average grant date fair value per share for the stock option grants during the years ended December 31, 2020 and 2019 was $11.58 and $9.72, respectively. As of December 31, 2020, the total unrecognized compensation related to unvested stock option awards granted was $28.0 million, which the Company expects to recognize over a weighted-average period of approximately 2.8 years. Performance-Based Restricted Stock Units (“PSUs”) and Restricted Stock Units (“RSUs”) In June 2019, the Company granted 567,509 PSUs, with a grant date fair value of $13.37. Vesting of the PSUs was dependent upon the satisfaction of both a service condition and a performance condition, which is an IPO or a change of control. The Company began recording compensation expense related to the PSUs upon the declaration of the Company’s IPO becoming effective on August 5, 2020, as the performance conditions were satisfied. The compensation expense was determined using the original grant date fair value and is being recognized over the remaining service period The Company’s PSU and RSU activity for the years ended December 31, 2020 and 2019 was as follows: Number of Shares Weighted Average Grant Price Unvested as of December 31, 2018 - $ - Granted 567,509 13.37 Unvested as of December 31, 2019 567,509 $ 13.37 Granted 270,718 19.87 Forfeited (7,386 ) 18.00 Vested (285,375 ) 13.37 Unvested as of December 31, 2020 545,466 $ 16.53 Restricted Stock Awards (“RSAs”) The Company’s RSA activity for the years ended December 31, 2020 and 2019 was as follows: Number of Shares Weighted Average Grant Price Unvested as of December 31, 2018 - $ - Granted 11,449 13.37 Vested (11,449 ) 13.37 Unvested as of December 31, 2019 - $ - Granted 34,051 16.85 Vested (34,051 ) 16.85 Unvested as of December 31, 2020 - $ - The following table summarizes the total stock-based compensation expense for the stock options, PSUs, RSUs and RSAs recorded in the consolidated statements of operations and comprehensive loss for the years ended December 31, 2020 and 2019 (in thousands): Year Ended December 31, 2020 2019 Cost of products sold $ 440 $ 209 Research and development 1,002 656 Selling, general and administrative 10,661 2,129 Total stock-based compensation $ 12,103 $ 2,994 Employee Stock Purchase Plan The 2020 Employee Stock Purchase Plan (“2020 ESPP”), which permits employees to purchase shares of the Company’s common stock, became effective on August 5, 2020 and 387,063 shares of common stock were authorized for sale under the 2020 ESPP. As of December 31, 2020, there were no purchases of shares under the 2020 ESPP as the program does not become effective until February 2021.

Net Loss Per Common Share

Net Loss Per Common Share	12 Months Ended
Net Loss Per Common Share	Dec. 31, 2020
Earnings Per Share [Abstract]
Net Loss Per Common Share	Note 17—Net Loss Per Common Share Basic net loss per common share is computed by dividing net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the period. Diluted net loss per common share excludes the potential impact of the Company’s convertible notes, convertible preferred stock, common stock options, PSUs, RSUs and warrants because their effect would be anti-dilutive due to the Company’s net loss. Since the Company had a net loss in the periods presented, basic and diluted net loss per common share are the same. The table below provides potentially dilutive securities not included in the calculation of the diluted net loss per common share because to do so would be anti-dilutive: Year Ended December 31, Shares issuable upon: 2020 2019 Conversion of Series A preferred stock — 391,210 Conversion of Series B preferred stock — 3,088,444 Conversion of Series C preferred stock — 4,499,921 Conversion of Series D preferred stock — 8,200,297 Exercise of stock options 3,403,607 2,041,205 Exercise of common stock warrants 824,608 509,562 Exercise of preferred stock warrants — 446,990 Vesting of PSUs and RSUs 545,466 — Total 4,773,681 19,177,629 For the year ended December 31, 2019, the PSUs are not included in the above table as awards with performance conditions are not included in the calculation of diluted earnings per share until the performance conditions for the PSU are considered probable.

401(k) Retirement Plan

401(k) Retirement Plan	12 Months Ended
401(k) Retirement Plan	Dec. 31, 2020
Compensation And Retirement Disclosure [Abstract]
401(k) Retirement Plan	Note 18—401(k) Retirement Plan The Company has a 401(k) retirement savings plan that provides retirement benefits to substantially all full-time U.S. employees. Eligible employees may contribute a percentage of their annual compensation, subject to Internal Revenue Service limitations. The Company did not provide any contributions to the 401(k) retirement savings plan for the years ended December 31, 2020 and 2019.

Income Taxes

Income Taxes	12 Months Ended
Income Taxes	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Note 19—Income Taxes The components of pretax loss from operations for the years ended December 31, 2020 and 2019 are as follows: December 31, 2020 2019 U.S. domestic $ (102,048 ) $ (97,091 ) Foreign 90 52 Pretax loss from operations $ (101,958 ) $ (97,039 ) The components of income tax expense for continuing operations are as follows: December 31, 2020 2019 Current tax provision: Federal $ — $ — State 23 — Foreign — — Total provision for income taxes $ 23 $ — The provision for state income taxes for the year ended December 31, 2020 was less than $0.1 million. There was no provision for federal, state or foreign income taxes recorded for the year ended December 31,2019. Current income taxes are based upon the year’s income taxable for federal, state and foreign tax reporting purposes. Deferred income taxes (benefits) are provided for certain income and expenses, which are recognized in different periods for tax and financial reporting purposes. Deferred tax assets and liabilities are computed for differences between the consolidated financial statements and tax bases of assets and liabilities that will result in taxable or deductible amounts in the future based on enacted tax laws and rates applicable to the period in which the differences are expected to affect taxable income, and NOL carryforwards and R&D tax credit carryforwards. A reconciliation of the expected tax computed at the U.S. statutory federal income tax rate to the total expense for income taxes for the years ended December 31, 2020 and 2019 is as follows (dollars in thousands): Year Ended December 31, 2020 2019 Income tax benefit at federal statutory rate $ (21,411 ) 21.00 % $ (20,378 ) 21.00 % Adjustments for tax effects of: State taxes, net (2,237 ) 2.19 % (1,315 ) 1.35 % Permanent adjustments 968 (0.95 )% 567 (0.58 )% Interest expense — 0.00 % 230 (0.24 )% Warrants 1,167 (1.14 )% 253 (0.26 )% Research and development credit (5,870 ) 5.76 % (53 ) 0.05 % Unrecognized tax benefit 1,761 (1.73 )% 16 (0.02 )% Valuation allowance 26,619 (26.11 )% 20,500 (21.11 )% Rate change (737 ) 0.72 % 223 (0.23 )% Other (237 ) 0.23 % (43 ) 0.19 % Income tax expense $ 23 (0.03 )% $ — — Significant components of the Company’s deferred tax assets and liabilities as of December 31, 2020 and 2019 were as follows (in thousands): December 31, 2020 2019 Deferred tax assets: Net operating losses $ 68,727 $ 45,455 Stock-based compensation 1,225 720 Research and development credit 7,225 3,116 Accrued vacation 390 187 Accrued expenses 745 484 IRC 263A — 239 Intangible assets 3,863 3,047 Lease liability 439 605 Other 196 153 Total gross deferred tax assets 82,810 54,006 Valuation allowance (79,782 ) (52,949 ) Net deferred tax asset 3,028 1,057 Deferred tax liabilities: Property and equipment (1,979 ) (450 ) Prepaid expenses (642 ) (122 ) Right of use assets (349 ) (485 ) IRC 263A (58 ) — Total deferred tax liabilities (3,028 ) (1,057 ) Net deferred tax assets (liabilities) $ — $ — In assessing the realizability of deferred tax assets as of December 31, 2020 and 2019, management considered whether it is more likely than not that some portion or all of the deferred tax assets will be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible or the NOL carryforwards and R&D credit carryforwards will be used. The Company has determined it is more likely than not that its net deferred tax assets will not be realized. Accordingly, a valuation allowance has been recorded as of December 31, 2020 and 2019, to fully offset the net deferred tax assets of $79.8 million and $52.9 million, respectively. As of December 31, 2020, the Company had approximately $303.5 million of NOL carryforwards available for federal tax purposes which begin to expire in December 31, 2031. As a result of the Tax Act of 2017, for U.S. income tax purposes, NOLs generated prior to December 31, 2017 can still be carried forward for up to 20 years, but NOLs generated after December 31, 2017 carryforward indefinitely, but are limited to 80% utilization against taxable income. Of the total federal NOL of $303.5 million, $108.2 million will begin to expire in 2031 and $195.3 million will not expire but will only offset 80% of future taxable income. On March 27, 2020, the Coronavirus Aid Relief and Economic Security Act (“CARES Act”) was signed into law in response to the economic challenges facing US businesses. Under the CARES Act, the Internal Revenue Code was amended to allow federal NOLs to be carried back five years to offset previous years income, or carried forward indefinitely to offset 100% of taxable income for the tax year 2020 and 80% of taxable income for tax years 2021 and thereafter. On December 27, 2020, the United States enacted the Consolidated Appropriations Act of 2021 (“CAA”). The CAA includes provisions extending certain CARES Act provisions and adds coronavirus relief and tax and health extenders. The Company will continue to evaluate the impact of the CAA and its impact on its consolidated financial statements in 2021 and beyond. As of December 31, 2020, the Company also had approximately $74.9 million of state NOL carryforwards. The state NOLs begin to expire in December 31, 2029. As of December 31, 2020, the Company had approximately $0.5 million of NOL carryforwards available for foreign tax purposes. Belgium NOLs do not expire. As of December 31, 2020, the Company had approximately $6.6 million of R&D credit carryforwards available for federal tax purposes, which begin to expire in December 31, 2031. As of December 31, 2020, the Company also had approximately $4.8 million of R&D credit carryforwards for California. The state R&D credits do not expire. NOL carryforwards may be subject to a substantial annual limitation due to ownership change limitations that may have occurred or that could occur in the future, as required by Section 382 of the Internal Revenue Code of 1986, as amended (the “Code”), as well as similar state and foreign provisions. These ownership changes may limit the amount of NOL and R&D credit carryforwards that can be used annually to offset future taxable income and tax, respectively. In general, an “ownership change” as defined by Section 382 of the Code results from a transaction or series of transactions over a three-year period resulting in an ownership change of more than 50% of the outstanding stock of a company by certain stockholders. The Company has not completed a study to assess whether an ownership change has occurred or whether there have been multiple ownership changes since the Company’s formation due to the complexity and cost associated with such study, and the fact that there may be additional such ownership changes in the future. The Company conducts intensive research and experimentation activities, generating R&D tax credits for Federal and state purposes under Section 41 of the Code. The Company has not performed a formal study validating these credits claimed in the tax returns. Once a study is prepared, the amount of R&D tax credits available could vary from what was originally claimed on the tax returns. The following table summarizes the changes to unrecognized tax benefits as of December 31, 2020 and 2019 (in thousands): December 31, 2020 2019 Balance at beginning of year $ 1,539 $ 1,523 Increases (decreases) related to prior year tax positions 1,210 (493 ) Increases related to current year tax positions 648 509 Balance at end of year $ 3,397 $ 1,539 As of December 31, 2020, the Company has unrecognized tax benefits of $3.4 million of which $3.1 million will affect the effective tax rate if recognized when the Company no longer has a valuation allowance offsetting its deferred tax assets. The Company does not anticipate that there will be a significant change in unrecognized tax benefits over the next 12 months. The Company is subject to U.S. federal and various state tax as well as Belgium tax jurisdictions. Since the Company formed in 2011, all filed tax returns are subject to examination. Generally, the tax years remain open for examination by the federal statute under a three-year statute of limitation; however, states generally keep their statutes open for four years. However, the Company’s tax years from inception are subject to examination by the United States and California taxing authorities due to the carry forward of unused NOLs and R&D credits. The Company’s practice is to recognize interest and/or penalties related to income tax matters in income tax benefit. The Company had no accrual for interest and penalties on its consolidated balance sheets and has not recognized interest and/or penalties in the consolidated statements of operations and comprehensive loss for the years ended December 31, 2020 and 2019.

Related Party Transactions

Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions	Note 20—Related Party Transactions The Company licenses certain patent rights from a former director and shareholder. The license agreement provides for royalty payments to the shareholder of 3% of net product sales, as defined in the agreement. Royalties earned prior to the director’s resignation were less than $0.1 million for both the years ended December 31, 2020 and 2019. Additionally, the former director and shareholder also works for one of the Company’s customers and can significantly influence the customer to purchase the Company’s product. Prior to the director’s resignation, the Company recorded sales to this customer of $0.5 million and $0.3 million for the years ended December 31, 2020 and 2019, respectively. The Company has a consulting agreement with the chairman of the Company’s board of directors. The Company recorded $0.2 million for both the years ended December 31, 2020 and 2019, in SG&A expense in the consolidated statements of operations and comprehensive loss, for the consulting services. With the completion of the IPO, the performance condition was satisfied for certain PSUs granted to the chairman of the Company’s board of directors. The Company recorded $4.6 million of stock-based compensation expense for these awards for the year ended December 31, 2020 in SG&A expense in the consolidated statement of operations and comprehensive loss. The Company had a consulting agreement with an officer of the Company in 2019, prior to his full-time employment. The Company recorded $0.3 million for the year ended December 31, 2019, included in SG&A expense in the consolidated statement of operations and comprehensive loss, for the consulting services. The Company had a consulting arrangement with a current director and officer of the Company, prior to his full-time employment. The Company recorded $0.4 million for the year ended December 31, 2019 included in SG&A expense in the consolidated statement of operations and comprehensive loss, for the consulting services. Multiple preferred stock shareholders entered into the 2018 Convertible Notes and 2019 Convertible Notes that also contained detached warrants. Additionally, Orbimed Royalty Opportunities II, LP and Deerfield Private Design Fund II, L.P. entered into the 2019 Credit Agreement with the Company in 2019 for a total of $70.0 million with $40.0 million being drawn as of December 31, 2020 and 2019. The Company recorded $5.5 million and $21.4 million for the years ended December 31, 2020 and 2019, respectively, in interest expense related to these debt agreements.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”).
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of Acutus Medical, Inc. and its wholly-owned subsidiary Acutus Medical NV (“Acutus NV”), which was incorporated under the laws of Belgium in August 2013. All intercompany balances and transactions have been eliminated in consolidation.
Use of Estimates and Assumptions	Use of Estimates and Assumptions The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue, expenses and disclosures of contingent assets and liabilities. The most significant estimates and assumptions in the Company’s consolidated financial statements include, but are not limited to, revenue recognition, useful lives of intangible assets, assessment of impairment of goodwill, provisions for income taxes, measurement of operating lease liabilities, and the fair value of common stock, stock options, warrants, embedded derivative in convertible notes, intangible assets, contingent consideration and goodwill. These estimates and assumptions are based on current facts, historical experience and various other factors believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and the recording of revenue and expenses that are not readily apparent from other sources. Actual results could differ from those estimates.
Segments	Segments Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business in one operating segment.
Cash and Cash Equivalents and Restricted Cash	Cash and Cash Equivalents and Restricted Cash The Company considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. All of the Company’s cash equivalents have liquid markets and high credit ratings. The Company maintains its cash in bank deposits and other accounts, the balances of which, at times and as of December 31, 2020 and 2019, exceeded federally insured limits. Restricted cash serves as collateral for the Company’s corporate credit card program. The following table reconciles cash and restricted cash in the consolidated balance sheets to the totals shown on the consolidated statements of cash flows (in thousands). December 31, December 31, 2020 2019 Cash and cash equivalents $ 25,234 $ 9,452 Restricted cash 150 150 Total cash, cash equivalents and restricted cash $ 25,384 $ 9,602
Marketable Securities	Marketable Securities The Company considers its debt securities to be available-for-sale securities. Available-for-sale securities are classified as cash equivalents, short-term marketable securities or long-term marketable securities based on the maturity date at time of purchase and their availability to meet current operating requirements. Marketable securities that mature in three months or less from the date of purchase are classified as cash equivalents. Marketable securities, excluding cash equivalents, that mature in one year or less are classified as short-term available-for-sale securities and are reported as a component of current assets. Securities that are classified as available-for-sale are measured at fair value with temporary unrealized gains and losses reported in other comprehensive loss, and as a component of stockholders’ equity (deficit) until their disposition or maturity. See “Fair Value Measurements” below. The Company reviews all available-for-sale securities at each period end to determine if they remain available-for-sale based on the Company’s current intent and ability to sell the security if it is required to do so. Realized gains and losses from the sale of marketable securities, if any, are calculated using the specific-identification method. Marketable securities are subject to a periodic impairment review. The Company may recognize an impairment charge when a decline in the fair value of investments below the cost basis is determined to be other-than-temporary. In determining whether a decline in market value is other-than-temporary, various factors are considered, including the cause, duration of time and severity of the impairment, any adverse changes in the investees’ financial condition and the Company’s intent and ability to hold the security for a period of time sufficient to allow for an anticipated recovery in market value. Declines in value judged to be other-than-temporary are included in the Company’s consolidated statements of operations and comprehensive loss. The Company did not record any other-than-temporary impairments related to marketable securities in the Company’s consolidated statements of operations and comprehensive loss for the
Concentrations of Credit Risk and Off-Balance Sheet Risk	Concentrations of Credit Risk and Off-Balance Sheet Risk Financial instruments that potentially subject the Company to credit risk consist principally of cash, cash equivalents, restricted cash, accounts receivable and marketable securities. Cash and restricted cash are maintained in accounts with financial institutions, which, at times may exceed the Federal depository insurance coverage of $0.25 million. The Company has not experienced losses on these accounts and management believes, based upon the quality of the financial institutions, that the credit risk with regard to these deposits is not significant. The Company’s marketable securities portfolio consists primarily of investments in money market funds, commercial paper, U.S. treasury securities, asset-backed securities and short-term high credit quality corporate debt securities.
Revenue from Contracts with Customers	Revenue from Contracts with Customers The Company accounts for revenue earned from contracts with customers under Accounting Standards Codification (“ASC”) 606, Revenue from Contracts with Customers • Step 1: Identify the contract with the customer. • Step 2: Identify the performance obligations in the contract. • Step 3: Determine the transaction price. • Step 4: Allocate the transaction price to the performance obligations in the contract. • Step 5: Recognize revenue when, or as, the company satisfies a performance obligation. The Company usually places its medical diagnostic equipment, AcQMap System, at customer sites under loan agreements and generates revenue from the sale of disposable products used with the AcQMap System. Disposable products include AcQMap Catheters and AcQGuide Steerable Sheaths. The Company provides the disposable products in exchange for consideration, which occurs when a customer submits a purchase order and the Company provides disposables at the agreed upon prices in the invoice. Generally, customers purchase disposable products using separate purchase orders after the equipment has been provided to the customer for free with no binding agreement or requirement to purchase any disposable products. The Company also sells the AcQMap System to customers along with software updates on a when-and-if-available basis and equipment service. The Company has elected the practical expedient and accounting policy election to account for the shipping and handling as activities to fulfill the promise to transfer the disposable products and not as a separate performance obligation. During the year ended December 30, 2020, the Company entered into deferred equipment agreements that are generally structured such that the Company agrees to provide an AcQMap System at no up-front charge, with title of the device transferring to the customer at the end of the contract term, in exchange for the customer’s commitment to purchase disposables at a specified price over the term of the agreement, which generally ranges from two to four years. The Company determined that the deferred equipment agreements include embedded sales-type leases. The Company allocates contract consideration under deferred equipment agreements containing fixed annual disposable purchase commitments to the underlying lease and non-lease components at contract inception. The Company expenses the cost of the device at the inception of the agreement and records a financial lease asset equal to the gross consideration allocated to the lease. The lease asset will be reduced by payments for minimum disposable purchases that are allocated to the lease. The following table sets forth the Company’s revenue for disposables, systems, and service/other for the years ended December 31, 2020 and 2019 (in thousands): Year Ended December 31, 2020 2019 Acutus Direct Disposables $ 5,221 $ 2,764 Systems 1,660 — Service/Other 91 19 Total Acutus direct revenue 6,972 2,783 Distribution agreements 1,492 53 Total revenue $ 8,464 $ 2,836 The Company’s contracts only include fixed consideration. There are no discounts, rebates, returns or other forms of variable consideration. Customers are generally required to pay within 30 to 60 days. The delivery of disposable products are performance obligations satisfied at a point in time. The disposable products are shipped Free on Board (“FOB”) shipping point or FOB destination. For disposable products that are shipped FOB shipping point, the customer has the significant risks and rewards of ownership and legal title to the assets when the disposable products leave the Company’s shipping facilities, thus the customer obtains control and revenue is recognized at that point in time. Revenue is recognized on delivery for disposable products shipped via FOB destination. The installation and delivery of the AcQMap System is satisfied at a point in time when the installation is complete, which is when the customer can benefit and has control of the system. The Company’s software updates and equipment service performance obligations are satisfied evenly over time as the customer simultaneously receives and consumes the benefits of the Company’s performance for these services throughout the service period. The Company allocates the transaction price to each performance obligation identified in the contract based on the relative standalone selling price (“SSP”). The Company determines SSP for the purposes of allocating the transaction price to each performance obligation based on the adjusted market assessment approach that maximizes the use of observable inputs, which includes, but is not limited to, transactions where the specific performance obligations are sold separately, list prices and offers to customers. The Company’s contracts with customers generally have an expected duration of one year or less, and therefore the Company has elected the practical expedient in ASC 606 to not disclose information about its remaining performance obligations. Any incremental costs to obtain contracts are recorded as selling, general and administrative expense as incurred due to the short duration of the Company’s contracts. The Company’s contract balances consisted solely of accounts receivable as of December 31, 2020 and 2019. In May 2020, the Company entered into bi-lateral distribution agreements with Biotronik SE & Co. KG (“Biotronik”) (the “Bi-Lateral Distribution Agreements”). Pursuant to the Bi-Lateral Distribution Agreements, the Company obtained a non-exclusive license to distribute a range of Biotronik’s products and accessories in the United States, Canada, China, Hong Kong and multiple Western European countries under the Company’s private label. Moreover, if an investigational device exemption (“IDE”) clinical trial is required for these products to obtain regulatory approval in the United States, or a clinical trial is required for these products to obtain regulatory approval in China, the Company will obtain an exclusive distribution right in such territories for a term of up to five years commencing on the date of regulatory approval if the Company covers the cost of the IDE or other clinical trial and the Company conducts such study within a specified period. Biotronik also agreed to distribute the Company’s products and accessories in Germany, Japan, Mexico, Switzerland and multiple countries in Asia-Pacific, Eastern Europe, the Middle East and South America. The Company also granted Biotronik a co-exclusive right to distribute these products in Hong Kong. Each party will pay to the other party specified transfer prices on the sale of the other party’s products and, accordingly, will earn a distribution margin on the sale of the other party’s products. The following table provides revenue by geographic location for the years ended December 31, 2020 and 2019 (in thousands): Year Ended December 31, 2020 2019 Acutus Direct United States $ 4,625 $ 738 Europe 2,347 2,045 Total Acutus direct revenue 6,972 2,783 Distribution Agreements United States 229 — Europe 1,263 53 Total revenue through distribution 1,492 53 Total revenue $ 8,464 $ 2,836
Inventory	Inventory Inventory is comprised of raw materials, direct labor and manufacturing overhead and is stated at the lower of cost (first-in, first-out basis) or net realizable value. The Company recorded write-downs for excess and obsolete inventory based on management’s review of inventories on hand, compared to estimated future usage and sales, shelf-life and assumptions about the likelihood of obsolescence of $0.1 million and $0.7 million, for the years ended December 31, 2020 and 2019, respectively.
Accounts Receivable	Accounts Receivable Trade accounts receivable are recorded net of allowances for uncollectible accounts. The Company evaluates the collectability of its accounts receivable based on various factors including historical experience, the length of time the receivables are past due and the financial health of the customer. The Company reserves specific receivables if collectability is no longer reasonably assured. Based upon the assessment of these factors, the Company did not record an allowance for uncollectible accounts as of December 31, 2020 or 2019.
Property and Equipment, Net	Property and Equipment, Net Property and equipment are recorded at cost. Depreciation and amortization are provided using the straight-line method over the estimated useful lives of the related assets, generally three to five years, or, in the case of leasehold improvements, over the lesser of the useful life of the related asset or the lease term.
Intangible Assets	Intangible Assets Intangible assets consist of acquired developed technology, acquired in-process technology, trademarks and trade names and a customer-related intangible which were acquired as part of the acquisition of Rhythm Xience, Inc. (“Rhythm Xience”) in June 2019. The Company determines the appropriate useful life of its finite-lived intangible assets by performing an analysis of expected cash flows of the acquired assets. Finite-lived intangible assets are amortized over their estimated useful lives using the straight-line method, which approximates the pattern in which the economic benefits are consumed. Acquired in-process technology was classified as an indefinite-lived intangible asset, until the receipt of U.S. Food and Drug Administration (“FDA”) approval for the technology in January 2020. Once the FDA approval was received, the in-process technology was classified as a finite-lived intangible and amortization for in-process technology began. Indefinite-lived intangible assets are tested for impairment at least annually and are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Indefinite-lived intangible assets are impaired if their estimated fair values are less than their carrying value.
Goodwill	Goodwill Goodwill represents the excess of the purchase price of an entity over the estimated fair value of the assets acquired and liabilities assumed, and it is presented as goodwill in the accompanying consolidated balance sheets. Under ASC 350, Intangibles – Goodwill and Other
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company reviews long-lived assets, including property and equipment and finite-lived intangible assets, for impairment whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. An impairment loss is recognized when the asset’s carrying value exceeds the total undiscounted cash flows expected from its use and eventual disposition. The amount of the impairment loss is determined as the excess of the carrying value of the asset over its fair value. For the year ended December 31, 2019, the Company recorded a $0.8 million impairment of its property and equipment resulting from the release of a second generation of the Company’s AcQMap System. For the year ended December 31, 2020, the Company determined that there was no impairment of property and equipment. For the years ended December 31, 2020 and 2019, the Company did not have an impairment of the intangible assets.
Foreign Currency Translation and Transactions	Foreign Currency Translation and Transactions The assets, liabilities and results of operations of Acutus NV are measured using their functional currency, the Euro, which is the currency of the primary foreign economic environment in which this subsidiary operates. Upon consolidating this entity with the Company, its assets and liabilities are translated to U.S. dollars at currency exchange rates as of the balance sheet date and its revenues and expenses are translated at the weighted-average currency exchange rates during the applicable reporting periods. Translation adjustments resulting from the process of translating this entity’s financial statements are reported in accumulated other comprehensive income (loss) in the consolidated balance sheets and foreign currency translation adjustment in the consolidated statements of operations and comprehensive loss.
Lessee Leases	Lessee Leases The Company accounts for its leases under ASC 842, Leases In calculating the right-of-use asset and lease liability, the Company elects to combine lease and non-lease components. The Company excludes short-term leases having initial terms of 12 months or less from the new guidance as an accounting policy election.
Cost of Products Sold	Cost of Products Sold Cost of products sold includes raw materials, direct labor, manufacturing overhead, shipping and receiving costs and other less significant indirect costs related to the production of the Company’s products.
Research and Development	Research and Development The Company is actively engaged in new product research and development efforts. Research and development expenses consist primarily of salaries and employee-related costs (including stock-based compensation) for personnel directly engaged in research and development activities, clinical trial expenses, equipment costs, material costs, allocated rent and facilities costs and depreciation. Research and development expenses also include payments for the asset acquisition from Biotronik and VascoMed GmbH (collectively, the “Biotronik Parties”) for certain licenses of patents, technology, know-how rights and equipment (the “Biotronik Asset Acquisition”). Research and development expenses relating to possible future products are expensed as incurred. The Company also accrues and expenses costs for activities associated with clinical trials performed by third parties as incurred. All other costs relative to setting up clinical trial sites are expensed as incurred. Clinical trial site costs related to patient enrollment are accrued as patients are entered into the trials.
Selling, General and Administrative	Selling, General and Administrative Selling, general and administrative (“SG&A”) expenses consist primarily of salaries and employee-related costs (including stock-based compensation) for personnel in sales, executive, finance and other administrative functions, allocated rent and facilities costs, legal fees relating to intellectual property and corporate matters, professional fees for accounting and consulting services, marketing costs and insurance costs. The Company expenses all SG&A costs as incurred.
Fair Value Measurements	Fair Value Measurements Fair value measurements are based on the premise that fair value is an exit price representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the following three-tier fair value hierarchy has been used in determining the inputs used in measuring fair value: Level 1—Quoted prices in active markets for identical assets or liabilities. Level 2—Observable inputs other than Level 1 prices for similar assets or liabilities that are directly or indirectly observable in the marketplace. Level 3—Unobservable inputs which are supported by little or no market activity and that are financial instruments whose values are determined using pricing models, discounted cash flow methodologies or similar techniques, as well as instruments for which the determination of fair value requires significant judgment or estimation. Financial instruments measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Management’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. The use of different assumptions and/or estimation methodologies may have a material effect on estimated fair values. Accordingly, the fair value estimates disclosed or initial amounts recorded may not be indicative of the amount that the Company or holders of the instruments could realize in a current market exchange. There were no transfers made among the three levels in the fair value hierarchy for the years ended December 31, 2020 and 2019. As of December 31, 2020 and 2019, the Company’s cash (excluding cash equivalents which are recorded at fair value on a recurring basis), restricted cash, accounts receivable, accounts payable and accrued expenses were carried at cost, which approximates the fair values due to the short-term nature of the instruments. The carrying amount of the Company’s long-term debt approximates fair value due to its variable market interest rate and management’s opinion that current rates and terms that would be available to the Company with the same maturity and security structure would be essentially equivalent to that of the Company’s long-term debt. Certain features of the convertible notes were determined to be an embedded derivative requiring separate measurement from the loan host instrument. The following tables classify the Company’s financial assets and liabilities measured at fair value on a recurring basis into the fair value hierarchy as of December 31, 2020 and 2019 (in thousands): Fair Value Measured as of December 31, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fair Value at December 31, 2020 Assets included in: Cash and cash equivalents Money market securities $ 19,070 $ — $ — $ 19,070 Marketable securities at fair value Corporate debt securities — 31,353 — 31,353 U.S. treasury securities — 20,531 — 20,531 Commercial paper — 53,955 — 53,955 Asset-backed securities — 8,726 — 8,726 Total fair value $ 19,070 $ 114,565 $ — $ 133,635 Liabilities included in: Contingent consideration $ — $ — $ 9,300 $ 9,300 Total fair value $ — $ — $ 9,300 $ 9,300 Fair Value Measured as of December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fair Value at December 31, 2019 Assets included in: Cash and cash equivalents Money market securities $ 8,901 $ — $ — $ 8,901 Marketable securities at fair value Corporate debt securities — 28,224 — 28,224 Asset-backed securities — 17,121 — 17,121 U.S. treasury securities — 5,032 — 5,032 Commercial paper — 11,974 — 11,974 Total fair value $ 8,901 $ 62,351 $ — $ 71,252 Liabilities included in: Contingent consideration $ — $ — $ 13,900 $ 13,900 Common and preferred stock warrant liability — — 8,919 8,919 Total fair value $ — $ — $ 22,819 $ 22,819 The fair value of the Company’s money market funds is determined using quoted market prices in active markets for identical assets. The Company’s portfolio of marketable securities is comprised of commercial paper, asset-backed securities, U.S. treasury securities and short-term highly liquid, high credit quality corporate debt securities. The fair value for the available-for-sale marketable securities is determined based on trade prices in active markets for identical assets (Level 1 inputs) or valuation models using inputs that are observable either directly or indirectly (Level 2 inputs), such as quoted prices for similar assets, yield curve, volatility factors, credit spreads, default rates, loss severity, current market and contractual prices for the underlying instruments, broker and dealer quotes, as well as other relevant economic measures. The following table presents changes in Level 3 liabilities measured at fair value for the years ended December 31, 2020 and 2019 (in thousands): Common and Preferred Stock Warrant Liability Contingent Consideration Embedded Derivative in 2018 Convertible Notes Total Balance, December 31, 2018 $ 6,842 $ — $ 5,568 $ 12,410 Issuance of preferred stock warrants in conjunction with debt 872 — — 872 Conversion of convertible notes — — (6,282 ) (6,282 ) Fair value of contingent consideration - Rhythm Xience acquisition — 13,400 — 13,400 Change in fair value 1,205 500 714 2,419 Balance, December 31, 2019 $ 8,919 $ 13,900 $ — $ 22,819 Payment of contingent consideration — (2,500 ) — (2,500 ) Issuance of preferred stock for contingent consideration — (2,197 ) — (2,197 ) Reclassification of warrant liability to stockholders' equity (14,474 ) — — (14,474 ) Change in fair value 5,555 97 — 5,652 Balance, December 31, 2020 $ — $ 9,300 $ — $ 9,300 Unrealized gains and losses associated with liabilities within the Level 3 category include changes in fair value that were attributable to both observable (e.g., changes in market interest rates) and unobservable (e.g., changes in unobservable long-dated volatilities) inputs. In June 2019, the convertible notes were converted into shares of the Company’s Series D convertible preferred stock. The fair value of the common stock and preferred stock warrant liability was estimated using a Monte Carlo simulation in the first quarter of 2019 and as an output of the Hybrid Method for the remaining quarters of 2019 and the first and second quarter of 2020. The underlying equity included in the Monte Carlo simulation and the Hybrid Method was determined based on the equity value implied from the preferred stock transactions and from examination of income and market approaches for measurement dates in which a preferred transaction was not applicable. Additionally, the expected IPO value was considered in the determination of the equity value. The fair value of the warrants was impacted by the model selected as well as assumptions surrounding unobservable inputs including the underlying equity value, risk-free interest rate, expected dividend yield, contractual term and expected volatility. On August 10, 2020 when the warrants were converted and became equity classified warrants, the fair value of the common and preferred stock warrant liability was estimated using a Black-Scholes model. The underlying equity included in the Black-Scholes model was based on the IPO share price of $18.00. August 10, December 31, 2020 2019 Risk-free interest rate 0.39% 1.59% - 1.60% Expected dividend yield — — Contractual term in years 7.8 - 8.8 0.7 - 1.0 Expected volatility 65.0% 60.0% - 110.5% The fair value of the contingent consideration from the acquisition of Rhythm Xience represents the estimated fair value of future payments due to the sellers of Rhythm Xience based on the achievement of certain milestones and revenue-based targets in certain years. The initial fair value of the revenue-based contingent consideration was calculated through the use of a Monte Carlo simulation using revenue projections for the respective earn-out period, corresponding targets and approximate timing of payments as outlined in the purchase agreement. The analyses used the following assumptions: (i) expected term; (ii) risk-adjusted net sales or earnings; (iii) risk-free interest rate; and (iv) expected volatility of earnings. Estimated payments, as determined through the respective model, were further discounted by a credit spread assumption to account for credit risk. The fair value of the milestones-based contingent consideration was determined by probability weighting and discounting to the respective valuation date at the Company’s cost of debt. The Company’s cost of debt was determined by performing a synthetic credit rating for the Company and selecting yields based on companies with a similar credit rating. The contingent consideration is revalued to fair value each period, and any increase or decrease is recorded in operating loss. The fair value of the contingent consideration may be impacted by certain unobservable inputs, most significantly with regard to discount rates, expected volatility and historical and projected performance. Significant changes to these inputs in isolation could result in a significantly different fair value measurement. The weighted-average (in aggregate) significant unobservable inputs (Level 3 inputs) used in measuring the contingent consideration from the acquisition of Rhythm Xience as of December 31, 2020, December 31, 2019 and June 18, 2019 (acquisition date) were as follows: December 31, 2020 December 31, 2019 June 18, 2019 (Acquisition Date) Risk-free interest rate 0.20% 1.60% 1.80% Expected term in years 1.0 - 2.0 1.0 - 2.0 1.0 - 2.0 Expected volatility 17.2% 11.8% 11.6% As of June 12, 2019 (conversion date), the fair value of the embedded derivative of $6.3 million was based on the difference between the fair value of the Series D convertible preferred stock issued upon the conversion of the 2018 Convertible Notes, as defined below, of $31.4 million, or $16.67 per share, and the discounted conversion price of $25.1 million, or $13.33 per share.
Stock-Based Compensation	Stock-Based Compensation The Company accounts for all stock-based payments to employees and non-employees, including grants of stock options, restricted stock awards (“RSAs”), restricted stock units (“RSUs”) and restricted stock units with non-market performance and service conditions (“PSUs”) to be recognized in the consolidated financial statements, based on their respective grant date fair values. The Company estimates the fair value of stock option grants using the Black-Scholes option pricing model. The RSAs, RSUs and PSUs are valued based on the fair value of the Company’s common stock on the date of grant. The assumptions used in calculating the fair value of stock-based awards represent management’s best estimates and involve inherent uncertainties and the application of management’s judgment. The Company expenses stock-based compensation related to stock options, RSAs and RSUs over the requisite service period. As the PSUs have a performance condition, compensation expense was recognized for each vesting tranche over the respective requisite service period of each tranche upon the IPO closing on August 10, 2020, when the Company’s management deemed it probable that the performance conditions were satisfied. The Company recognized a cumulative true-up adjustment related to PSUs once the conditions became probable of being satisfied as the related service period had been completed in a prior period. All stock-based compensation costs are recorded in cost of products sold, research and development expense or SG&A expense in the consolidated statements of operations and comprehensive loss based upon the respective employee’s or non-employee’s roles within the Company. Forfeitures are recorded as they occur. See also “ Note 16—Stock-Based Compensation
Income Taxes	Income Taxes Income taxes are recorded in accordance with ASC 740, Income Taxes The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit would more likely than not be realized assuming examination by the taxing authority. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances. To date, there have been no interest or penalties charged in relation to the unrecognized tax benefits.
Warrant Liability	Warrant Liability The Company accounted for certain common stock warrants and convertible preferred stock warrants outstanding as a liability, in accordance with ASC 815, Derivatives and Hedging and upon conversion to equity-classified warrants, and any change in fair value was recognized in the consolidated statements of operations and comprehensive loss. In connection with the IPO on August 10, 2020, the common stock warrants and convertible preferred stock warrants that had been liability-classified were automatically converted into an equal number of warrants to purchase common stock and became equity-classified. The fair value of the outstanding liability on the conversion date was reclassified to additional paid-in capital in the Company’s consolidated balance sheet.
Asset Acquisitions (Research and Development—License Acquired)	Asset Acquisitions (Research and Development—License Acquired) The Company accounts for asset acquisitions, where substantially all of the fair value of the assets acquired is concentrated in a group of similar assets (e.g., intellectual property) and therefore the acquisitions do not constitute a business, in accordance with ASC 805, Business Combinations
Business Combinations	Business Combinations The Company accounts for business acquisitions using the acquisition method of accounting based on ASC 805, which requires recognition and measurement of all identifiable assets acquired and liabilities assumed at their fair value as of the date control is obtained. The Company determines the fair value of assets acquired and liabilities assumed based upon its best estimates of the acquisition-date fair value of assets acquired and liabilities assumed in the acquisition. Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired. Subsequent adjustments to fair value of any contingent consideration are recorded to the Company’s consolidated statements of operations and comprehensive loss.
Recently Adopted Accounting Pronouncements and Accounting Pronouncements to Be Adopted	Recently Adopted Accounting Pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) issued ASC 842 in order to increase transparency and comparability among organizations by, among other provisions, recognizing lease assets and lease liabilities on the balance sheet for those leases classified as operating leases under previous U.S. GAAP. For public companies, ASC 842 is effective for fiscal years beginning after December 15, 2018 (including interim periods within those periods) using a modified retrospective approach and early adoption is permitted. In transition, entities may also elect a package of practical expedients that must be applied in its entirety to all leases commencing before the adoption date, unless the lease is modified, and permits entities to not reassess (a) the existence of a lease, (b) lease classification or (c) determination of initial direct costs, as of the adoption date, which effectively allows entities to carryforward accounting conclusions under previous U.S. GAAP. In July 2018, the FASB issued Accounting Standards Update (“ASU”) No. 2018-11, Leases (Topic 842): Targeted Improvements , which provides entities an optional transition method to apply the guidance under ASC 842 as of the adoption date, rather than as of the earliest period presented. The Company adopted ASC 842 on January 1, 2019, using the optional transition method by recording a right-of-use asset of $3.0 million, a lease liability of $3.6 million and eliminated deferred rent of $0.6 million; there was no effect on opening accumulated deficit. In adopting the new standard, the Company elected to apply the practical expedients regarding the identification of leases, lease classification, indirect costs and the combination of lease and non-lease components. In October 2016, the FASB issued ASU No. 2016-16, Income Taxes: Intra-Entity Transfers of Assets Other Than Inventory . ASU No. 2016-16 requires an entity to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. The amendments eliminate the exception for an intra-entity transfer of an asset other than inventory. The amendments in ASU No. 2016-16 are effective for non-public business entities for annual periods beginning after December 15, 2018, and interim periods within annual periods beginning after December 15, 2018. The Company adopted ASU No. 2016-16 on January 1, 2019 and there was no impact from the adoption. In January 2017, the FASB issued ASU No. 2017-04, Intangibles-Goodwill and Other: Simplifying the Test for Goodwill Impairment In July 2017, the FASB issued ASU No. 2017-11, Earnings Per Share (Topic 260); Distinguishing Liabilities from Equity (Topic 480) Derivatives and Hedging In August 2018, the FASB issued ASU No. 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement Accounting Pronouncements to Be Adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326) In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
Summary of Significant Accounting Policies (Tables)	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Cash and Restricted Cash	The following table reconciles cash and restricted cash in the consolidated balance sheets to the totals shown on the consolidated statements of cash flows (in thousands). December 31, December 31, 2020 2019 Cash and cash equivalents $ 25,234 $ 9,452 Restricted cash 150 150 Total cash, cash equivalents and restricted cash $ 25,384 $ 9,602
Summary of Disaggregation of Revenue	The following table sets forth the Company’s revenue for disposables, systems, and service/other for the years ended December 31, 2020 and 2019 (in thousands): Year Ended December 31, 2020 2019 Acutus Direct Disposables $ 5,221 $ 2,764 Systems 1,660 — Service/Other 91 19 Total Acutus direct revenue 6,972 2,783 Distribution agreements 1,492 53 Total revenue $ 8,464 $ 2,836
Summary of Revenue from External Customers by Geographic Areas	The following table provides revenue by geographic location for the years ended December 31, 2020 and 2019 (in thousands): Year Ended December 31, 2020 2019 Acutus Direct United States $ 4,625 $ 738 Europe 2,347 2,045 Total Acutus direct revenue 6,972 2,783 Distribution Agreements United States 229 — Europe 1,263 53 Total revenue through distribution 1,492 53 Total revenue $ 8,464 $ 2,836
Summary of Fair Value, Liabilities Measured on Recurring Basis	The following tables classify the Company’s financial assets and liabilities measured at fair value on a recurring basis into the fair value hierarchy as of December 31, 2020 and 2019 (in thousands): Fair Value Measured as of December 31, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fair Value at December 31, 2020 Assets included in: Cash and cash equivalents Money market securities $ 19,070 $ — $ — $ 19,070 Marketable securities at fair value Corporate debt securities — 31,353 — 31,353 U.S. treasury securities — 20,531 — 20,531 Commercial paper — 53,955 — 53,955 Asset-backed securities — 8,726 — 8,726 Total fair value $ 19,070 $ 114,565 $ — $ 133,635 Liabilities included in: Contingent consideration $ — $ — $ 9,300 $ 9,300 Total fair value $ — $ — $ 9,300 $ 9,300 Fair Value Measured as of December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fair Value at December 31, 2019 Assets included in: Cash and cash equivalents Money market securities $ 8,901 $ — $ — $ 8,901 Marketable securities at fair value Corporate debt securities — 28,224 — 28,224 Asset-backed securities — 17,121 — 17,121 U.S. treasury securities — 5,032 — 5,032 Commercial paper — 11,974 — 11,974 Total fair value $ 8,901 $ 62,351 $ — $ 71,252 Liabilities included in: Contingent consideration $ — $ — $ 13,900 $ 13,900 Common and preferred stock warrant liability — — 8,919 8,919 Total fair value $ — $ — $ 22,819 $ 22,819
Summary of Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation	The following table presents changes in Level 3 liabilities measured at fair value for the years ended December 31, 2020 and 2019 (in thousands): Common and Preferred Stock Warrant Liability Contingent Consideration Embedded Derivative in 2018 Convertible Notes Total Balance, December 31, 2018 $ 6,842 $ — $ 5,568 $ 12,410 Issuance of preferred stock warrants in conjunction with debt 872 — — 872 Conversion of convertible notes — — (6,282 ) (6,282 ) Fair value of contingent consideration - Rhythm Xience acquisition — 13,400 — 13,400 Change in fair value 1,205 500 714 2,419 Balance, December 31, 2019 $ 8,919 $ 13,900 $ — $ 22,819 Payment of contingent consideration — (2,500 ) — (2,500 ) Issuance of preferred stock for contingent consideration — (2,197 ) — (2,197 ) Reclassification of warrant liability to stockholders' equity (14,474 ) — — (14,474 ) Change in fair value 5,555 97 — 5,652 Balance, December 31, 2020 $ — $ 9,300 $ — $ 9,300
Weighted average unobservable inputs to measure contingent consideration	The weighted-average (in aggregate) significant unobservable inputs (Level 3 inputs) used in measuring the common and preferred stock warrant liabilities as of August 10, 2020 (date of conversion to equity classified warrants) and December 31, 2019 were as follows: August 10, December 31, 2020 2019 Risk-free interest rate 0.39% 1.59% - 1.60% Expected dividend yield — — Contractual term in years 7.8 - 8.8 0.7 - 1.0 Expected volatility 65.0% 60.0% - 110.5% December 31, 2020 December 31, 2019 June 18, 2019 (Acquisition Date) Risk-free interest rate 0.20% 1.60% 1.80% Expected term in years 1.0 - 2.0 1.0 - 2.0 1.0 - 2.0 Expected volatility 17.2% 11.8% 11.6%

Asset Acquisition and Busines_2

Asset Acquisition and Business Combination (Tables)	12 Months Ended
Asset Acquisition and Business Combination (Tables)	Dec. 31, 2020
Business Combination Recognized Identifiable Assets Acquired Goodwill And Liabilities Assumed Net [Abstract]
Summary of Purchase Price Allocation To The Assets Acquired and Liabilities Assumed	The following table summarizes the allocation of the purchase price to the assets acquired and liabilities assumed for the Rhythm Xience Acquisition (in thousands): Accounts receivable, net $ 3 Prepaid expenses and other current assets 8 Property and equipment, net 3 Intangible assets 4,360 Goodwill 12,026 Contingent consideration (13,400 ) Cash consideration $ 3,000
Summary of Unaudited Pro Forma Financial Information	The following unaudited pro forma financial information presents results of operations as if the Rhythm Xience Acquisition had occurred on January 1, 2019 (in thousands): Year Ended December 31, 2019 Revenue $ 2,933 Net loss $ (97,850 )

Marketable Securities (Tables)

Marketable Securities (Tables)	12 Months Ended
Marketable Securities (Tables)	Dec. 31, 2020
Investments Debt And Equity Securities [Abstract]
Summary of Marketable Securities	Marketable securities consisted of the following as of December 31, 2020 and 2019 (in thousands): December 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Available-for-sale securities - short-term: Corporate debt securities $ 31,359 $ — $ (6 ) $ 31,353 U.S. treasury securities 20,533 — (2 ) 20,531 Commercial paper 53,955 — — 53,955 Total available-for-sale securities - short-term 105,847 — (8 ) 105,839 Asset-backed securities, long-term 8,726 — 8,726 Total available-for-sale securities $ 114,573 $ — $ (8 ) $ 114,565 December 31, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Available-for-sale securities - short-term: Corporate debt securities $ 28,204 $ 20 $ — $ 28,224 Asset-backed securities 17,108 13 — 17,121 U.S. treasury securities 5,020 12 — 5,032 Commercial paper 11,974 — — 11,974 Total available-for-sale securities $ 62,306 $ 45 $ — $ 62,351

Inventory (Tables)

Inventory (Tables)	12 Months Ended
Inventory (Tables)	Dec. 31, 2020
Inventory Disclosure [Abstract]
Summary of Inventory	Inventory as of December 31, 2020 and 2019 consisted of the following (in thousands): December 31, December 31, 2020 2019 Raw materials $ 7,960 $ 5,492 Work in process 1,267 1,605 Finished goods 3,731 1,327 Total inventory $ 12,958 $ 8,424

Lessor Sales-Type Leases (Table

Lessor Sales-Type Leases (Tables)	12 Months Ended
Lessor Sales-Type Leases (Tables)	Dec. 31, 2020
Leases [Abstract]
Estimated Future Maturities of Customer Sales-Type Lease Receivables	As of December 31, 2020, estimated future maturities of customer sales-type lease receivables for each of the following years were as follows (in thousands): Year ending December 31, 2021 $ 367 Year ending December 31, 2022 338 Year ending December 31, 2023 107 Year ending December 31, 2024 27 Year ending December 31, 2025 - Lease receivable $ 839

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	12 Months Ended
Property and Equipment, Net (Tables)	Dec. 31, 2020
Property Plant And Equipment [Abstract]
Summary of Property and Equipment, Net	The Company’s property and equipment, net, consisted of the following as of December 31, 2020 and 2019 (in thousands): December 31, December 31, 2020 2019 Medical diagnostic equipment $ 13,242 $ 5,492 Furniture and fixtures 388 159 Office equipment 1,392 1,321 Laboratory equipment and software 3,491 2,807 Leasehold improvements 608 507 Construction in process 468 306 Total property and equipment 19,589 10,592 Less: accumulated depreciation (7,233 ) (6,165 ) Property and equipment, net $ 12,356 $ 4,427

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
Goodwill and Intangible Assets (Tables)	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Summary Of Goodwill And Intangible Assets Activities	The tables below summarize goodwill and intangible assets activities as of December 31, 2020 and 2019 (in thousands): Goodwill Intangible Assets Balance, December 31, 2018 $ — $ — Rhythm Xience Acquisition 12,026 4,360 Amortization expense — (250 ) Balance, December 31, 2019 12,026 4,110 Biotronik License Agreement — 2,000 Amortization expense — (457 ) Balance, December 31, 2020 $ 12,026 $ 5,653
Summary of Finite and Indefinite Lived Intangible Assets	Estimated Useful Weighted Average Remaining Life (in years) Life (in years) Intangible Assets Accumulated Amortization December 31, 2020 Developed technology 10 8.6 $ 4,200 $ (600 ) $ 3,600 Customer-related intangible 5 3.5 100 (30 ) 70 Licensed intangibles 10 9.9 2,000 (17 ) 1,983 Total $ 6,300 $ (647 ) $ 5,653 Estimated Useful Weighted Average Remaining Life (in years) Life (in years) Intangible Assets Accumulated Amortization December 31, 2019 Developed technology 10 9.5 $ 3,600 $ (180 ) $ 3,420 In-process technology indefinite 600 — 600 Trademarks and trade names 0.5 — 60 (60 ) — Customer-related intangible 5 4.5 100 (10 ) 90 Total $ 4,360 $ (250 ) $ 4,110
Summary Of Remaining Amortization Expense	The following table shows the remaining amortization expense associated with amortizable intangible assets as of December 31, 2020 (in thousands): Developed Technology Customer- Related Intangible Licensed Intangibles Total Amortization Year ending December 31, 2021 $ 420 $ 20 $ 200 $ 640 Year ending December 31, 2022 420 20 200 640 Year ending December 31, 2023 420 20 200 640 Year ending December 31, 2024 420 10 200 630 Year ending December 31, 2025 420 — 200 620 Thereafter 1,500 — 983 2,483 Total $ 3,600 $ 70 $ 1,983 $ 5,653

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
Accrued Liabilities (Tables)	Dec. 31, 2020
Payables And Accruals [Abstract]
Summary Of Accrued Liabilities	Accrued liabilities consisted of the following as of December 31, 2020 and 2019 (in thousands): December 31, December 31, 2020 2019 Compensation and related expenses $ 6,250 $ 3,785 Professional fees 120 188 Deferred revenue 301 311 Sales and use tax 169 151 Biotronik Asset Acquisition - accrued purchase price — 5,000 Other 468 641 Total accrued liabilities $ 7,308 $ 10,076

Debt (Tables)

Debt (Tables)	12 Months Ended
Debt (Tables)	Dec. 31, 2020
Debt Instruments [Abstract]
Summary of Outstanding Debt	Outstanding debt as of December 31, 2020 and 2019 consisted of the following (in thousands): December 31, December 31, 2020 2019 2019 Credit Agreement (1) $ 44,550 $ 44,550 Total debt, gross 44,550 44,550 Less: Unamortized debt discount and fees (5,539 ) (6,306 ) Total long-term debt $ 39,011 $ 38,244
Schedule of Shares Issued Upon Conversion	In June 2019, in conjunction with the Series D preferred stock issuance, the 2019 Convertible Notes and the 2018 Convertible Notes, along with accrued interest thereon, were converted into shares of Series D convertible preferred stock. As such, the convertible noteholders received an aggregate of 4,108,478 shares of Series D convertible preferred stock for the conversion of all outstanding 2019 Convertible Notes and 2018 Convertible Notes at a conversion price of $$16.67 per share and $13.33 per share (including the 20.0% discount provided for in the 2018 Convertible Notes), respectively. The following table provides the shares issued upon conversion: Conversion on June 12, 2019 Stated Interest Rate Conversion Price Conversion Price per Share Face Value (in thousands) Accrued Interest (in thousands) Total Conversion Amount (in thousands) Shares Issued 2019 Convertible Notes 13% Lowest price paid by cash investor in 2019 Series D preferred stock issuance $ 16.67 $ 37,000 $ 66 $ 37,066 2,223,913 2018 Convertible Notes 10% 80% of lowest price paid by cash investor in 2019 Series D preferred stock issuance $ 13.33 22,815 2,313 25,128 1,884,565 80% of lowest price paid by cash investor in 2019 Series D preferred stock issuance $ 59,815 $ 2,379 $ 62,194 4,108,478

Operating Leases (Tables)

Operating Leases (Tables)	12 Months Ended
Operating Leases (Tables)	Dec. 31, 2020
Leases [Abstract]
Summary Of Quantitative Information About Operating Leases	The following table summarizes quantitative information about the Company’s operating leases for the years ended December 31, 2020 and 2019 (dollars in thousands): Year Ended December 31, 2020 2019 Operating cash flows from operating leases $ 1,013 $ 972 Right-of-use assets exchanged for operating lease liabilities $ - $ 2,978 Weighted average remaining lease term – operating leases (in years) 1.6 3.2 Weighted average discount rate – operating leases 7.0 % 7.0 %
Summary Of Components Of Lease Cost	The following table provides the components of the Company’s lease cost for the years ended December 31, 2020 and 2019 (in thousands): Year Ended December 31, 2020 2019 Operating leases Operating lease cost $ 864 $ 864 Variable lease cost 311 234 Total rent expense $ 1,175 $ 1,098
Summary Of Future Minimum Payments Under The Non-cancelable Operating Leases	As of December 31, 2020, future minimum payments under the non-cancelable operating leases were as follows (in thousands): Year ending December 31, 2021 $ 1,044 Year ending December 31, 2022 1,074 Year ending December 31, 2023 51 Year ending December 31, 2024 51 Year ending December 31, 2025 — Total 2,220 Less: present value discount (153 ) Operating lease liabilities $ 2,067

Warrants (Tables)

Warrants (Tables)	12 Months Ended
Warrants (Tables)	Dec. 31, 2020
Warrants And Rights Note Disclosure [Abstract]
Schedule of Outstanding Warrants to Purchase the Company's Common Stock	As of December 31, 2020 and 2019, the outstanding warrants to purchase the Company’s common stock were comprised of the following: Equity Upon Exercise (After Conversion) Exercise Price Expiration Date December 31, 2020 December 31, 2019 Warrants issued in 2015 Common stock $ 5.25 1/30/25 3,808 7,616 Warrants issued with 2018 Convertible Notes Common stock $ 0.10 6/7/28 373,810 501,946 Warrants issued with 2018 Term Loan Common stock $ 16.67 7/31/28 26,998 26,998 Warrants issued with 2019 Credit Agreement Common stock $ 16.67 5/20/29 419,992 419,992 Total Warrants 824,608 956,552
Schedule of Warrant Activity	The Company’s warrant activity for the years ended December 31, 2020 and 2019 is as follows: Warrants Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Balance - December 31, 2018 543,793 $ 1.10 9.3 Granted 419,992 16.67 8.5 Exercised (7,233 ) 8.29 5.1 Balance - December 31, 2019 956,552 $ 7.88 8.4 Exercised (131,944 ) 0.25 7.4 Balance - December 31, 2020 824,608 $ 9.10 7.5

Convertible Preferred Stock (Ta

Convertible Preferred Stock (Tables)	12 Months Ended
Convertible Preferred Stock (Tables)	Dec. 31, 2020
Temporary Equity [Abstract]
Schedule of Initial Conversion Price per Share for each Series of Convertible Preferred Stock	The initial conversion price per share for each series of convertible preferred stock was the original issue price applicable to such series as follows: Series Conversion Price Series A convertible preferred stock $ 8.295 Series B convertible preferred stock $ 13.370 Series C convertible preferred stock $ 16.667 Series D convertible preferred stock $ 16.667

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
Stock-Based Compensation (Tables)	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Schedule of Estimate of the Fair Value of Stock Option	The following assumptions were used to estimate the fair value of stock option for the years ended December 31, 2020 and 2019: Year Ended December 31, 2020 2019 Risk-free interest rate 0.35% - 0.9% 1.6% - 2.1% Expected dividend yield — — Expected term in years 7.0 6.4 - 10.0 Expected volatility 60% - 80% 80%
Summary of Stock Option Activity	The following table summarizes stock option activity during the years ended December 31, 2020 and 2019: Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value (in thousands) Outstanding as of December 31, 2018 1,587,410 $ 8.13 8.0 $ 6,012 Options granted 540,157 13.37 Options exercised (27,806 ) 3.87 $ 251 Options forfeited (58,556 ) 9.86 Outstanding as of December 31, 2019 2,041,205 $ 9.52 7.7 $ 10,782 Options granted 1,794,895 16.91 Options exercised (172,312 ) 7.52 $ 1,660 Options forfeited (260,181 ) 12.10 Outstanding as of December 31, 2020 3,403,607 $ 13.32 8.1 $ 52,866 Options vested and exercisable as of December 31, 2020 1,403,764 $ 9.55 6.6 $ 27,035
Schedule of PSU and RSA Activity	The Company’s PSU and RSU activity for the years ended December 31, 2020 and 2019 was as follows: Number of Shares Weighted Average Grant Price Unvested as of December 31, 2018 - $ - Granted 567,509 13.37 Unvested as of December 31, 2019 567,509 $ 13.37 Granted 270,718 19.87 Forfeited (7,386 ) 18.00 Vested (285,375 ) 13.37 Unvested as of December 31, 2020 545,466 $ 16.53
Schedule of RSA Activity	The Company’s RSA activity for the years ended December 31, 2020 and 2019 was as follows: Number of Shares Weighted Average Grant Price Unvested as of December 31, 2018 - $ - Granted 11,449 13.37 Vested (11,449 ) 13.37 Unvested as of December 31, 2019 - $ - Granted 34,051 16.85 Vested (34,051 ) 16.85 Unvested as of December 31, 2020 - $ -
Summary of the Total Stock-Based Compensation Expense for the Stock Options, PSUs and RSAs Recorded in the Condensed Consolidated Statements of Operations and Comprehensive Loss	The following table summarizes the total stock-based compensation expense for the stock options, PSUs, RSUs and RSAs recorded in the consolidated statements of operations and comprehensive loss for the years ended December 31, 2020 and 2019 (in thousands): Year Ended December 31, 2020 2019 Cost of products sold $ 440 $ 209 Research and development 1,002 656 Selling, general and administrative 10,661 2,129 Total stock-based compensation $ 12,103 $ 2,994

Net Loss Per Common Share (Tabl

Net Loss Per Common Share (Tables)	12 Months Ended
Net Loss Per Common Share (Tables)	Dec. 31, 2020
Earnings Per Share [Abstract]
Summary of Calculation of the Diluted Net Loss per Common Share	The table below provides potentially dilutive securities not included in the calculation of the diluted net loss per common share because to do so would be anti-dilutive: Year Ended December 31, Shares issuable upon: 2020 2019 Conversion of Series A preferred stock — 391,210 Conversion of Series B preferred stock — 3,088,444 Conversion of Series C preferred stock — 4,499,921 Conversion of Series D preferred stock — 8,200,297 Exercise of stock options 3,403,607 2,041,205 Exercise of common stock warrants 824,608 509,562 Exercise of preferred stock warrants — 446,990 Vesting of PSUs and RSUs 545,466 — Total 4,773,681 19,177,629

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Schedule of Components of Pretax Loss from Operation	The components of pretax loss from operations for the years ended December 31, 2020 and 2019 are as follows: December 31, 2020 2019 U.S. domestic $ (102,048 ) $ (97,091 ) Foreign 90 52 Pretax loss from operations $ (101,958 ) $ (97,039 )
Schedule of Components of Income Tax Expense for Continuing Operations	The components of income tax expense for continuing operations are as follows: December 31, 2020 2019 Current tax provision: Federal $ — $ — State 23 — Foreign — — Total provision for income taxes $ 23 $ —
Schedule of Reconciliation of Expected Tax Computed at U.S. Statutory Federal Income Tax Rate to Total Expense for Income Taxes	A reconciliation of the expected tax computed at the U.S. statutory federal income tax rate to the total expense for income taxes for the years ended December 31, 2020 and 2019 is as follows (dollars in thousands): Year Ended December 31, 2020 2019 Income tax benefit at federal statutory rate $ (21,411 ) 21.00 % $ (20,378 ) 21.00 % Adjustments for tax effects of: State taxes, net (2,237 ) 2.19 % (1,315 ) 1.35 % Permanent adjustments 968 (0.95 )% 567 (0.58 )% Interest expense — 0.00 % 230 (0.24 )% Warrants 1,167 (1.14 )% 253 (0.26 )% Research and development credit (5,870 ) 5.76 % (53 ) 0.05 % Unrecognized tax benefit 1,761 (1.73 )% 16 (0.02 )% Valuation allowance 26,619 (26.11 )% 20,500 (21.11 )% Rate change (737 ) 0.72 % 223 (0.23 )% Other (237 ) 0.23 % (43 ) 0.19 % Income tax expense $ 23 (0.03 )% $ — —
Schedule of Components of Company's Deferred Tax Assets and Liabilities	Significant components of the Company’s deferred tax assets and liabilities as of December 31, 2020 and 2019 were as follows (in thousands): December 31, 2020 2019 Deferred tax assets: Net operating losses $ 68,727 $ 45,455 Stock-based compensation 1,225 720 Research and development credit 7,225 3,116 Accrued vacation 390 187 Accrued expenses 745 484 IRC 263A — 239 Intangible assets 3,863 3,047 Lease liability 439 605 Other 196 153 Total gross deferred tax assets 82,810 54,006 Valuation allowance (79,782 ) (52,949 ) Net deferred tax asset 3,028 1,057 Deferred tax liabilities: Property and equipment (1,979 ) (450 ) Prepaid expenses (642 ) (122 ) Right of use assets (349 ) (485 ) IRC 263A (58 ) — Total deferred tax liabilities (3,028 ) (1,057 ) Net deferred tax assets (liabilities) $ — $ —
Schedule of Changes to Unrecognized Tax Benefits	The following table summarizes the changes to unrecognized tax benefits as of December 31, 2020 and 2019 (in thousands): December 31, 2020 2019 Balance at beginning of year $ 1,539 $ 1,523 Increases (decreases) related to prior year tax positions 1,210 (493 ) Increases related to current year tax positions 648 509 Balance at end of year $ 3,397 $ 1,539

Organization and Description _2

Organization and Description of Business - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Date of incorporation	Mar. 25, 2011
Accumulated deficit	$ 361,015,000	$ 259,034,000	$ 0
Working capital deficit	$ 129,500,000	$ 50,500,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional information (Detail)	12 Months Ended
	Dec. 31, 2020USD ($)SegmentReportingUnit$ / shares	Dec. 31, 2019USD ($)	Jun. 12, 2019USD ($)$ / shares	Jan. 01, 2019USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of operating segment \| Segment	1
Other-than-temporary impairments related to marketable securities	$ 0	$ 0
Cash, FDIC insured amount	250,000
Inventory Write-down	100,000	700,000
Allowance for uncollectible accounts	$ 0	0
Number of reporting unit \| ReportingUnit	1
Impairment of property and equipment	$ 0	786,000
Impairment of intangible assets	0	0
Conversion amount			$ 59,815,000
Interest or penalties charged in relation to the unrecognized tax benefits	0
Right-of-use asset	1,669,000	2,341,000		$ 3,000,000
Lease liability	2,067,000			3,600,000
Deferred rent				600,000
Accumulated deficit	$ (361,015,000)	$ (259,034,000)		$ 0
ASU No. 2018-11 [Member]
Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 1, 2019
ASU No. 2016-16 [Member]
Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 1, 2019
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect		true
ASU No. 2017-04 [Member]
Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 1, 2019
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect		true
Change in Accounting Principle, Accounting Standards Update, Early Adoption		true
ASU No. 2017-11 [Member]
Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 1, 2019
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect		true
ASU No. 2018-13 [Member]
Summary Of Significant Accounting Policies [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted		true
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Jan. 1, 2019
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect		true
Embedded Derivative in 2018 Convertible Notes [Member]
Summary Of Significant Accounting Policies [Line Items]
Fair value of the embedded derivative			6,300,000
Conversion amount			$ 31,400,000
Conversion price per share \| $ / shares			$ 16.67
Discounted conversion price			$ 25,100,000
Discounted conversion price per share \| $ / shares			$ 13.33
IPO [Member]
Summary Of Significant Accounting Policies [Line Items]
Share price \| $ / shares	$ 18
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Customers payment period	30 days
Property and equipment, estimated useful lives	3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Customers payment period	60 days
Contracts with customers, expected duration	1 year
Property and equipment, estimated useful lives	5 years
Deferred Equipment Agreements [Member]
Summary Of Significant Accounting Policies [Line Items]
Cash, FDIC insured amount	$ 0
Deferred Equipment Agreements [Member] \| Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Contract term	2 years
Deferred Equipment Agreements [Member] \| Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Contract term	4 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Cash and Restricted Cash (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Cash and cash equivalents	$ 25,234	$ 9,452
Restricted cash	150	150
Total cash, cash equivalents and restricted cash	$ 25,384	$ 9,602	$ 9,775

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Summary of Disaggregation of Revenue (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Summary Of Significant Accounting Policies [Line Items]
Total revenue	$ 8,464	$ 2,836
Distribution Agreements [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	1,492	53
Acutus Direct Revenue [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	6,972	2,783
Acutus Direct Revenue [Member] \| Disposables [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	5,221	2,764
Acutus Direct Revenue [Member] \| Systems [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	1,660
Acutus Direct Revenue [Member] \| Product and Service, Other [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	$ 91	$ 19

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Summary of Revenue from External Customers by Geographic Areas (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Summary Of Significant Accounting Policies [Line Items]
Total revenue	$ 8,464	$ 2,836
Acutus Direct Revenue [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	6,972	2,783
Distribution Agreements [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	1,492	53
United States [Member] \| Acutus Direct Revenue [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	4,625	738
United States [Member] \| Distribution Agreements [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	229
Europe [Member] \| Acutus Direct Revenue [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	2,347	2,045
Europe [Member] \| Distribution Agreements [Member]
Summary Of Significant Accounting Policies [Line Items]
Total revenue	$ 1,263	$ 53

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Summary of Fair Value, Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets
Total Assets Fair Value	$ 133,635	$ 71,252
Liabilities
Total Liabilities Fair Value	9,300	22,819
Contingent Consideration [Member]
Liabilities
Total Liabilities Fair Value	9,300	13,900
Common and Preferred Stock Warrant Liability [Member]
Liabilities
Total Liabilities Fair Value		8,919
Money Market Securities [Member]
Assets
Money market securities	19,070	8,901
Corporate Debt Securities [Member]
Assets
Marketable securities	31,353	28,224
US Treasury Securities [Member]
Assets
Marketable securities	20,531	5,032
Commercial Paper [Member]
Assets
Marketable securities	53,955	11,974
Asset-backed Securities [Member]
Assets
Marketable securities	8,726	17,121
Fair Value, Inputs, Level 1 [Member]
Assets
Total Assets Fair Value	19,070	8,901
Fair Value, Inputs, Level 1 [Member] \| Money Market Securities [Member]
Assets
Money market securities	19,070	8,901
Fair Value, Inputs, Level 2 [Member]
Assets
Total Assets Fair Value	114,565	62,351
Fair Value, Inputs, Level 2 [Member] \| Corporate Debt Securities [Member]
Assets
Marketable securities	31,353	28,224
Fair Value, Inputs, Level 2 [Member] \| US Treasury Securities [Member]
Assets
Marketable securities	20,531	5,032
Fair Value, Inputs, Level 2 [Member] \| Commercial Paper [Member]
Assets
Marketable securities	53,955	11,974
Fair Value, Inputs, Level 2 [Member] \| Asset-backed Securities [Member]
Assets
Marketable securities	8,726	17,121
Fair Value, Inputs, Level 3 [Member]
Liabilities
Total Liabilities Fair Value	9,300	22,819
Fair Value, Inputs, Level 3 [Member] \| Contingent Consideration [Member]
Liabilities
Total Liabilities Fair Value	$ 9,300	13,900
Fair Value, Inputs, Level 3 [Member] \| Common and Preferred Stock Warrant Liability [Member]
Liabilities
Total Liabilities Fair Value		$ 8,919

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Summary of Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Detail) - USD ($) $ in Thousands	Jun. 12, 2019	Dec. 31, 2020	Dec. 31, 2019
Summary Of Significant Accounting Policies [Line Items]
Conversion of convertible notes	$ (62,194)
Reclassification of warrant liability to stockholders' equity		$ 14,474
Change in fair value of contingent consideration		97	$ 500
Fair Value, Inputs, Level 3 [Member]
Summary Of Significant Accounting Policies [Line Items]
Balance, December 31, 2018		22,819	12,410
Issuance of preferred stock warrants in conjunction with debt			872
Conversion of convertible notes			(6,282)
Fair value of contingent consideration			13,400
Payment of contingent consideration		(2,500)
Issuance of preferred stock for contingent consideration		(2,197)
Reclassification of warrant liability to stockholders' equity		(14,474)
Change in fair value of contingent consideration		5,652	2,419
Balance, December 31, 2019		9,300	22,819
Common and Preferred Stock Warrant Liability [Member] \| Fair Value, Inputs, Level 3 [Member]
Summary Of Significant Accounting Policies [Line Items]
Balance, December 31, 2018		8,919	6,842
Issuance of preferred stock warrants in conjunction with debt			872
Reclassification of warrant liability to stockholders' equity		(14,474)
Change in fair value of contingent consideration		5,555	1,205
Balance, December 31, 2019			8,919
Contingent Consideration [Member] \| Fair Value, Inputs, Level 3 [Member]
Summary Of Significant Accounting Policies [Line Items]
Balance, December 31, 2018		13,900
Fair value of contingent consideration			13,400
Payment of contingent consideration		(2,500)
Issuance of preferred stock for contingent consideration		(2,197)
Change in fair value of contingent consideration		97	500
Balance, December 31, 2019		$ 9,300	13,900
Embedded Derivative in 2018 Convertible Notes [Member] \| Fair Value, Inputs, Level 3 [Member]
Summary Of Significant Accounting Policies [Line Items]
Balance, December 31, 2018			5,568
Conversion of convertible notes			(6,282)
Change in fair value of contingent consideration			$ 714

Summary of Significant Accou_10

Summary of Significant Accounting Policies - Summary of Weighted Average Fair Value Assumptions on Common and Preferred Stock Warrant Liabilities (Detail) - Fair Value, Inputs, Level 3 [Member]	Aug. 10, 2020	Dec. 31, 2019
Measurement Input, Risk Free Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Common and preferred stock warrant liabilities, Fair value inputs	0.0039
Measurement Input, Price Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Common and preferred stock warrant liabilities, Fair value inputs	0.650
Minimum [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Common and preferred stock warrant liabilities, Fair value inputs		0.0159
Minimum [Member] \| Measurement Input, Maturity [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Common and preferred stock warrant liabilities, Fair value inputs	7 years 9 months 18 days	8 months 12 days
Minimum [Member] \| Measurement Input, Price Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Common and preferred stock warrant liabilities, Fair value inputs		0.600
Maximum [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Common and preferred stock warrant liabilities, Fair value inputs		0.0160
Maximum [Member] \| Measurement Input, Maturity [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Common and preferred stock warrant liabilities, Fair value inputs	8 years 9 months 18 days	1 year
Maximum [Member] \| Measurement Input, Price Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Common and preferred stock warrant liabilities, Fair value inputs		1.105

Summary of Significant Accou_11

Summary of Significant Accounting Policies - Summary of Weighted Average Fair Value Assumptions on Contingent Consideration (Detail) - Fair Value, Inputs, Level 3 [Member] - Rhythm Xience [Member]	Dec. 31, 2020	Dec. 31, 2019	Jun. 18, 2019
Measurement Input, Risk Free Interest Rate [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration from the acquisition, Fair value inputs	0.0020	0.0160	0.0180
Measurement Input, Price Volatility [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration from the acquisition, Fair value inputs	0.172	0.118	0.116
Minimum [Member] \| Measurement Input, Maturity [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration from the acquisition, Fair value inputs	0.010	0.010	0.010
Maximum [Member] \| Measurement Input, Maturity [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration from the acquisition, Fair value inputs	0.020	0.020	0.020

Asset Acquisition and Busines_3

Asset Acquisition and Business Combination - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 18, 2019	Feb. 29, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Research and development expense				$ 33,454	$ 23,029
Payments for contingent consideration				2,500
Goodwill			$ 12,026	12,026	12,026
Amortization of intangible assets				457	250
Biotronik Asset Acquisition [Member]
Business Acquisition [Line Items]
Consideration paid in cash					10,000
Equity interests issued and issuable					5,000
Consideration transferred				15,000
Payments for contingent consideration				2,000
Contingent milestone and royalty payments			10,000	8,000	10,000
Potential milestone payments capitalized				2,000
Biotronik Asset Acquisition [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Potential milestone payments payable				10,000
Biotronik Asset Acquisition [Member] \| Intellectual Property [Member]
Business Acquisition [Line Items]
Research and development expense				15,000
Rhythm Xience [Member]
Business Acquisition [Line Items]
Consideration paid in cash	$ 3,000
Payments for contingent consideration				2,500
Date of business acquisition	Jun. 18, 2019
Goodwill	$ 12,026
Contingent consideration liability	13,400			9,300
Business combination contingent consideration liability change in amount			500	$ 100
Revenue			100
Net loss			1,000
Transaction costs			$ 200		200
Income tax benefit					100
Interest expense					100
Amortization of intangible assets					200
Rhythm Xience [Member] \| SG&A Expense [Member]
Business Acquisition [Line Items]
Acquisition costs					$ 200
Rhythm Xience [Member] \| Earnout Consideration [Member]
Business Acquisition [Line Items]
Potential milestone payments payable	$ 17,000
Series D Convertible Preferred Stock [Member] \| Biotronik Asset Acquisition [Member]
Business Acquisition [Line Items]
Business consideration, number of equity interests issued and issuable				273,070
Equity interests issued and issuable				$ 5,000
Series D Convertible Preferred Stock [Member] \| Rhythm Xience [Member]
Business Acquisition [Line Items]
Business consideration, number of equity interests issued and issuable				119,993
Series D Convertible Preferred Stock [Member] \| Rhythm Xience [Member] \| Earnout Consideration [Member]
Business Acquisition [Line Items]
Equity interests issued and issuable		$ 2,200

Asset Acquisition and Busines_4

Asset Acquisition and Business Combination - Purchase Price Allocation (Detail) - USD ($) $ in Thousands	Jun. 18, 2019	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Goodwill		$ 12,026	$ 12,026
Rhythm Xience [Member]
Business Acquisition [Line Items]
Accounts receivable, net	$ 3
Prepaid expenses and other current assets	8
Property and equipment, net	3
Intangible assets	4,360
Goodwill	12,026
Contingent consideration	(13,400)	$ (9,300)
Cash consideration	$ 3,000

Asset Acquisition and Busines_5

Asset Acquisition and Business Combination - Summary of Unaudited Pro Forma Financial Information (Detail) - Rhythm Xience [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Business Acquisition [Line Items]
Revenue	$ 2,933
Net loss	$ (97,850)

Marketable Securities - Summary

Marketable Securities - Summary of Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 114,573	$ 62,306
Gross Unrealized Gains		45
Gross Unrealized Losses	(8)
Fair Value	114,565	62,351
Short-term debt [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	105,847
Gross Unrealized Losses	(8)
Fair Value	105,839
Corporate Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	31,359	28,204
Gross Unrealized Gains		20
Gross Unrealized Losses	(6)
Fair Value	31,353	28,224
US Treasury Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	20,533	5,020
Gross Unrealized Gains		12
Gross Unrealized Losses	(2)
Fair Value	20,531	5,032
Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	53,955	11,974
Fair Value	53,955	11,974
Asset-backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	8,726	17,108
Gross Unrealized Gains		13
Fair Value	$ 8,726	$ 17,121

Marketable Securities - Additio

Marketable Securities - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities	$ 114,565	$ 62,351
Debt securities, available-for-sale, maturity		1 year
Short-term debt [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities	$ 105,839
Debt securities, available-for-sale, maturity	1 year
Long-term debt [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities	$ 8,700
Debt securities, available-for-sale, maturity	2 years

Inventory - Summary of Inventor

Inventory - Summary of Inventory (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 7,960	$ 5,492
Work in process	1,267	1,605
Finished goods	3,731	1,327
Total inventory	$ 12,958	$ 8,424

Lessor Sales-Type Leases - Addi

Lessor Sales-Type Leases - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Lessor Lease Description [Line Items]
Lease revenue	$ 800,000	$ 0
Sales-type Lease, Income, Comprehensive Income [Extensible List]	us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
Lease receivable		$ 0
Prepaid Expenses and Other Current Assets [Member]
Lessor Lease Description [Line Items]
Lease receivable	$ 400,000
Other Assets [Member]
Lessor Lease Description [Line Items]
Lease receivable	$ 400,000

Lessor Sales-Type Leases - Esti

Lessor Sales-Type Leases - Estimated Future Maturities of Customer Sales-Type Lease Receivables (Detail) $ in Thousands	Dec. 31, 2020USD ($)
Leases [Abstract]
Year ending December 31, 2021	$ 367
Year ending December 31, 2022	338
Year ending December 31, 2023	107
Year ending December 31, 2024	27
Lease receivable	$ 839

Property and Equipment, Net - S

Property and Equipment, Net - Summary Of Property And Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 19,589	$ 10,592
Less: accumulated depreciation	(7,233)	(6,165)
Property and equipment, net	12,356	4,427
Medical diagnostic equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	13,242	5,492
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	388	159
Office equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	1,392	1,321
Laboratory equipment and software [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	3,491	2,807
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	608	507
Construction in process [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 468	$ 306

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Abstract]
Depreciation	$ 2,763,000	$ 2,280,000
Impairment of property and equipment	$ 0	$ 786,000

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Summary Of Goodwill and Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Indefinite Lived Intangible Assets By Major Class [Line Items]
Goodwill, Beginning Balance	$ 12,026
Goodwill, Ending Balance	12,026	$ 12,026
Intangible Assets, Beginning Balance	4,110
Intangible Assets, Amortization expense	(457)	(250)
Intangible Assets, Ending Balance	5,653	4,110
Rhythm Xience [Member]
Indefinite Lived Intangible Assets By Major Class [Line Items]
Goodwill, Acquisition		12,026
Intangible Assets, Acquisition		4,360
Intangible Assets, Amortization expense		$ (200)
Biotronik Asset Acquisition [Member]
Indefinite Lived Intangible Assets By Major Class [Line Items]
Intangible Assets, Acquisition	$ 2,000

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Summary of Finite and Indefinite Lived Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Finite And Indefinite Lived Intangible Assets [Line Items]
Finite Intangible Assets	$ 5,653	$ 4,110
Intangible Assets, Gross	6,300	4,360
Accumulated Amortization	(647)	(250)
Intangible Assets	$ 5,653	$ 4,110
Developed Technology [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Estimated Useful Life (in Years)	10 years	10 years
Weighted Average Remaining Life (in Years)	8 years 7 months 6 days	9 years 6 months
Finite Intangible Assets, Gross	$ 4,200	$ 3,600
Finite Intangible Assets, Accumulated Amortization	(600)	(180)
Finite Intangible Assets	$ 3,600	$ 3,420
Trademarks and Trade Names [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Estimated Useful Life (in Years)		6 months
Finite Intangible Assets, Gross		$ 60
Finite Intangible Assets, Accumulated Amortization		$ (60)
Customer-Related Intangible [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Estimated Useful Life (in Years)	5 years	5 years
Weighted Average Remaining Life (in Years)	3 years 6 months	4 years 6 months
Finite Intangible Assets, Gross	$ 100	$ 100
Finite Intangible Assets, Accumulated Amortization	(30)	(10)
Finite Intangible Assets	$ 70	90
Licensed Intangibles [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Estimated Useful Life (in Years)	10 years
Weighted Average Remaining Life (in Years)	9 years 10 months 24 days
Finite Intangible Assets, Gross	$ 2,000
Finite Intangible Assets, Accumulated Amortization	(17)
Finite Intangible Assets	$ 1,983
In-process Technology [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets, Gross		600
Indefinite-lived Intangible Assets		$ 600

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 457	$ 250

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets - Summary of remaining amortization expense associated with amortizable intangible assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Finite Lived Intangible Assets [Line Items]
Year ending December 31, 2021	$ 640
Year ending December 31, 2022	640
Year ending December 31, 2023	640
Year ending December 31, 2024	630
Year ending December 31, 2025	620
Thereafter	2,483
Finite Intangible Assets	5,653	$ 4,110
Developed Technology [Member]
Finite Lived Intangible Assets [Line Items]
Year ending December 31, 2021	420
Year ending December 31, 2022	420
Year ending December 31, 2023	420
Year ending December 31, 2024	420
Year ending December 31, 2025	420
Thereafter	1,500
Finite Intangible Assets	3,600	3,420
Customer-Related Intangible [Member]
Finite Lived Intangible Assets [Line Items]
Year ending December 31, 2021	20
Year ending December 31, 2022	20
Year ending December 31, 2023	20
Year ending December 31, 2024	10
Finite Intangible Assets	70	$ 90
Licensed Intangibles [Member]
Finite Lived Intangible Assets [Line Items]
Year ending December 31, 2021	200
Year ending December 31, 2022	200
Year ending December 31, 2023	200
Year ending December 31, 2024	200
Year ending December 31, 2025	200
Thereafter	983
Finite Intangible Assets	$ 1,983

Accrued Liabilities - Summary O

Accrued Liabilities - Summary Of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Payables And Accruals [Abstract]
Compensation and related expenses	$ 6,250	$ 3,785
Professional fees	120	188
Deferred revenue	301	311
Sales and use tax	169	151
Biotronik Asset Acquisition - accrued purchase price		5,000
Other	468	641
Total accrued liabilities	$ 7,308	$ 10,076

Debt - Summary of Outstanding D

Debt - Summary of Outstanding Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 44,550	$ 44,550
Less: Unamortized debt discount and fees	(5,539)	(6,306)
Total long-term debt	39,011	38,244
Two Thousand And Nineteen Convertible Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 44,550	$ 44,550

Debt - Summary of Outstanding_2

Debt - Summary of Outstanding Debt (Parenthetical) (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Two Thousand And Nineteen Credit Agreement [Member]
Debt Instrument [Line Items]
Debt instrument, fee amount	$ 4.6	$ 4.6

Debt - Additional Information (

Debt - Additional Information (Detail) - USD ($)	Jun. 12, 2019	May 20, 2019	Jun. 07, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jul. 31, 2018
Debt Instrument [Line Items]
Conversion amount	$ 59,815,000
Class of warrants, exercise price				$ 9.10	$ 7.88	$ 1.10
Payment for the extinguishment of term loan					$ 2,332,000
Loss on debt extinguishment					$ (1,447,000)
Issuance of Series D convertible preferred stock for 2018 Convertible Notes and 2019 Convertible Notes, Shares	4,108,478
Convertible Notes Payable [Member]
Debt Instrument [Line Items]
Conversion amount		$ 37,000,000
Debt instrument, interest rate		13.00%	10.00%
Long-term debt, maturity date		Dec. 31, 2019	Jun. 7, 2019
Minimum qualified equity financing amount	$ 23,000,000
Debt instrument, beneficial conversion feature				$ 13,500,000
Debt instrument convertible price percentage	80.00%
Convertible Notes Payable [Member] \| Automatic Conversion Feature
Debt Instrument [Line Items]
Minimum qualified equity financing amount	$ 20,000,000
2019 Convertible Notes [Member]
Debt Instrument [Line Items]
Conversion amount	$ 37,000,000
Debt instrument, interest rate	13.00%
Issuance of Series D convertible preferred stock for 2018 Convertible Notes and 2019 Convertible Notes, Shares	2,223,913
Conversion price per share	$ 16.67
2018 Convertible Notes [Member]
Debt Instrument [Line Items]
Conversion amount	$ 22,815,000
Debt instrument, interest rate	10.00%
Warrants liability fair value				$ 5,400,000
Class of warrants number of securities called by the warrants or rights				501,946
Debt instrument, Initial debt discount before inception				$ 20,300,000
Proceeds from issuance of convertible preferred stock, net of issuance costs			$ 22,800,000
Embedded derivative, fair value	$ 2,400,000
Loss on issuance of convertible notes and warrants				900,000
Issuance of Series D convertible preferred stock for 2018 Convertible Notes and 2019 Convertible Notes, Shares	1,884,565
Conversion price per share	$ 13.33
Series D Convertible Preferred Stock [Member]
Debt Instrument [Line Items]
Issuance of Series D convertible preferred stock for 2018 Convertible Notes and 2019 Convertible Notes, Shares	4,108,478				4,108,478
Series D Convertible Preferred Stock [Member] \| 2019 Convertible Notes [Member]
Debt Instrument [Line Items]
Proceeds from issuance of convertible preferred stock, net of issuance costs	$ 37,000,000
Series D Convertible Preferred Stock [Member] \| 2018 Convertible Notes [Member]
Debt Instrument [Line Items]
Embedded derivative, fair value				6,300,000
2018 Term Loan [Member]
Debt Instrument [Line Items]
Conversion amount							$ 15,000,000
Debt instrument, interest rate							8.95%
Debt instrument, fee amount				$ 100,000			$ 600,000
Long-term debt, maturity date							Jul. 1, 2023
Debt instrument, interest rate, increase (decrease)				5.00%
Debt instrument, direct fees				$ 100,000
Debt instrument, Initial debt discount before inception				1,100,000
Payment for the extinguishment of term loan				16,200,000
Loss on debt extinguishment				1,400,000
Write-off of deferred financing fees				900,000
Prepayment penalty				500,000
Prepayment fees				$ 100,000
2018 Term Loan [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate							7.04%
Two Thousand And Nineteen Credit Agreement [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate				7.75%
Debt instrument, fee amount				$ 4,600,000	$ 4,600,000
Warrants liability fair value				$ 900,000
Class of warrants number of securities called by the warrants or rights				419,992
Debt instrument, direct fees				$ 1,200,000
Two Thousand And Nineteen Credit Agreement [Member] \| Common Stock [Member]
Debt Instrument [Line Items]
Class of warrants, exercise price				$ 16.67
Two Thousand And Nineteen Credit Agreement [Member] \| Series C Convertible Preferred Stock [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate term				7.75% plus LIBOR
Class of warrants, exercise price				$ 16.67
Two Thousand And Nineteen Credit Agreement [Member] \| Series D Convertible Preferred Stock [Member]
Debt Instrument [Line Items]
Class of warrants, exercise price				$ 16.67
Two Thousand And Nineteen Credit Agreement [Member] \| Senior Term Loan [Member]
Debt Instrument [Line Items]
Conversion amount		$ 70,000,000
Proceeds from senior term loan		40,000,000
Debt instrument, remaining amount		30,000,000
Debt instrument unused borrowing capacity		$ 0
Debt instrument, fee amount				$ 4,600,000
Long-term debt, maturity date				May 20, 2024
Debt instrument, Initial debt discount before inception				$ 6,700,000
Default Event [Member] \| Senior Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, increase (decrease)				10.00%
2018 Term Loan [Member]
Debt Instrument [Line Items]
Warrants liability fair value				$ 300,000
Class of warrants number of securities called by the warrants or rights				26,998
2018 Term Loan [Member] \| Common Stock [Member]
Debt Instrument [Line Items]
Class of warrants, exercise price				$ 16.67
2018 Term Loan [Member] \| Series C Convertible Preferred Stock [Member]
Debt Instrument [Line Items]
Class of warrants, exercise price				16.67
2018 Term Loan [Member] \| Series D Convertible Preferred Stock [Member]
Debt Instrument [Line Items]
Class of warrants, exercise price				$ 16.67

Debt - Schedule of Shares Issue

Debt - Schedule of Shares Issued Upon Conversion (Detail)	Jun. 12, 2019USD ($)$ / sharesshares
Debt Instrument [Line Items]
Face Value	$ 59,815,000
Accrued Interest	2,379,000
Total Conversion Amount	$ 62,194,000
Shares Issued \| shares	4,108,478
2019 Convertible Notes [Member]
Debt Instrument [Line Items]
Stated Interest Rate	13.00%
Conversion Price per Share \| $ / shares	$ 16.67
Face Value	$ 37,000,000
Accrued Interest	66,000
Total Conversion Amount	$ 37,066,000
Shares Issued \| shares	2,223,913
2018 Convertible Notes [Member]
Debt Instrument [Line Items]
Stated Interest Rate	10.00%
Conversion Price per Share \| $ / shares	$ 13.33
Face Value	$ 22,815,000
Accrued Interest	2,313,000
Total Conversion Amount	$ 25,128,000
Shares Issued \| shares	1,884,565

Operating Leases - Additional I

Operating Leases - Additional Information (Detail)	12 Months Ended
Operating Leases - Additional Information (Detail)	Dec. 31, 2020ft²
Lessee, Lease, Description [Line Items]
Office space	50,800
Corporate Office Space and Manufacturing Facility
Lessee, Lease, Description [Line Items]
Lease expiration date	Dec. 31, 2022
Office Space And Manufacturing Facility
Lessee, Lease, Description [Line Items]
Operating lease option to extend renewal term description	five-year term
Office Space Zaventem Belgium
Lessee, Lease, Description [Line Items]
Office space	3,900
Lease expiration date	Dec. 31, 2021
Operating lease option to extend renewal term description	three-year term

Operating Leases - Summary Of Q

Operating Leases - Summary Of Quantitative Information About Operating Leases (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Lessee Disclosure [Abstract]
Operating cash flows from operating leases	$ 1,013	$ 972
Right-of-use assets exchanged for operating lease liabilities		$ 2,978
Weighted average remaining lease term – operating leases (in years)	1 year 7 months 6 days	3 years 2 months 12 days
Weighted average discount rate – operating leases	7.00%	7.00%

Operating Leases - Summary Of C

Operating Leases - Summary Of Components Of Lease Cost (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating leases
Operating lease cost	$ 864	$ 864
Variable lease cost	311	234
Total rent expense	$ 1,175	$ 1,098

Operating Leases - Summary Of F

Operating Leases - Summary Of Future Minimum Payments Under The Non-Cancelable Operating Leases (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2019
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
Year ending December 31, 2021	$ 1,044
Year ending December 31, 2022	1,074
Year ending December 31, 2023	51
Year ending December 31, 2024	51
Total	2,220
Less: present value discount	(153)
Operating lease liabilities	$ 2,067	$ 3,600

Warrants - Schedule of Outstand

Warrants - Schedule of Outstanding Warrants to Purchase the Company's Common Stock (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Class of Warrant or Right [Line Items]
Class of warrants, exercise price	$ 9.10	$ 7.88		$ 1.10
Class of Warrant or Right, Outstanding	824,608	956,552	7,233	543,793
Common Stock [Member] \| Warrants Issued in 2015 [Member]
Class of Warrant or Right [Line Items]
Equity Upon Exercise (After Conversion)	Common stock
Class of warrants, exercise price	$ 5.25
Expiration Date	Jan. 30, 2025
Class of Warrant or Right, Outstanding	3,808	7,616
Common Stock [Member] \| Warrants Issued with 2018 Convertible Notes [Member]
Class of Warrant or Right [Line Items]
Equity Upon Exercise (After Conversion)	Common stock
Class of warrants, exercise price	$ 0.10
Expiration Date	Jun. 7, 2028
Class of Warrant or Right, Outstanding	373,810	501,946
Common Stock [Member] \| Warrants Issued with 2018 Term Loan [Member]
Class of Warrant or Right [Line Items]
Equity Upon Exercise (After Conversion)	Common stock
Class of warrants, exercise price	$ 16.67
Expiration Date	Jul. 31, 2028
Class of Warrant or Right, Outstanding	26,998	26,998
Common Stock [Member] \| Warrants Issued with 2019 Credit Agreement [Member]
Class of Warrant or Right [Line Items]
Equity Upon Exercise (After Conversion)	Common stock
Class of warrants, exercise price	$ 16.67
Expiration Date	May 20, 2029
Class of Warrant or Right, Outstanding	419,992	419,992

Warrants - Schedule of Warrants

Warrants - Schedule of Warrants Activity (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Warrants And Rights Note Disclosure [Abstract]
Warrants, Beginning Balance	956,552	543,793
Warrants, Granted		419,992
Warrants, Exercised	(131,944)	(7,233)
Warrants, Ending Balance	824,608	956,552	543,793
Weighted Average Exercise Price, Beginning Balance	$ 7.88	$ 1.10
Weighted Average Exercise Price, Granted		16.67
Weighted Average Exercise Price, Exercised	0.25	8.29
Weighted Average Exercise Price, Ending Balance	$ 9.10	$ 7.88	$ 1.10
Weighted Average Remaining Contractual Life	7 years 6 months	8 years 4 months 24 days	9 years 3 months 18 days
Weighted Average Remaining Contractual Life, Granted		8 years 6 months
Weighted Average Remaining Contractual Life, Exercised	7 years 4 months 24 days	5 years 1 month 6 days

Warrants - Additional Informati

Warrants - Additional Information (Detail) - USD ($) $ in Thousands	Aug. 10, 2020	Dec. 31, 2019
Class of Warrant or Right [Line Items]
Common and preferred stock warrant liability		$ 8,919
ASC 815 [Member]
Class of Warrant or Right [Line Items]
Common and preferred stock warrant liability	$ 14,500

Convertible Preferred Stock - A

Convertible Preferred Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Aug. 10, 2020	Jun. 12, 2019	Feb. 29, 2020	Mar. 31, 2019	Jul. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Temporary Equity [Line Items]
Convertible preferred stock, shares authorized	5,000,000
Convertible preferred stock issued		4,108,478
Proceeds from issuance of convertible preferred stock							$ 66,563
Class of Warrant or Right, Outstanding				7,233		824,608	956,552	543,793
Firm Underwritten Commitment [Member] \| Prospective Event Trgerring Conversion of Temporary Equity into Permanent Equity [Member]
Temporary Equity [Line Items]
Stock issue share price per unit						$ 50
Firm Underwritten Commitment [Member] \| Prospective Event Trgerring Conversion of Temporary Equity into Permanent Equity [Member] \| Minimum [Member]
Temporary Equity [Line Items]
Sale of stock consideration received						$ 50,000
Series A Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Conversion of stock shares converted	391,210
Convertible preferred stock, shares authorized	0					0	3,848,696
Convertible preferred stock, par value						$ 0.001	$ 0.001
Issuance of Series A preferred stock for cashless warrant exercise				2,652
Series B Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Conversion of stock shares converted	3,088,444
Convertible preferred stock, shares authorized	0					0	30,032,100
Convertible preferred stock, par value						$ 0.001	$ 0.001
Series C Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Conversion of stock shares converted	4,499,921
Convertible preferred stock, shares authorized	0					0	48,184,000
Convertible preferred stock, par value						$ 0.001	$ 0.001
Series D Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Conversion of stock shares converted	8,593,360
Convertible preferred stock, shares authorized	0					0	90,000,000
Convertible preferred stock, par value						$ 0.001	$ 0.001
Convertible preferred stock issued		4,108,478					4,108,478
Series D Convertible Preferred Stock [Member] \| Private Placement [Member]
Temporary Equity [Line Items]
Convertible preferred stock issued					8,200,297
Embedded derivative included in Series D convertible preferred stock					$ 6,300
Series D Convertible Preferred Stock [Member] \| Private Placement [Member] \| $16.67 Per Share Series D Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible preferred stock issued					4,091,819
Price per share					$ 16.67
Proceeds from issuance of convertible preferred stock					$ 66,600
Offering costs					$ 1,600
Series D Convertible Preferred Stock [Member] \| Private Placement [Member] \| 2018 Convertible Notes [Member]
Temporary Equity [Line Items]
Convertible preferred stock issued					1,884,565
Price per share					$ 13.33
Proceeds from issuance of convertible preferred stock					$ 25,100
Series D Convertible Preferred Stock [Member] \| Private Placement [Member] \| 2019 Convertible Notes [Member]
Temporary Equity [Line Items]
Convertible preferred stock issued					2,223,913
Price per share					$ 16.67
Proceeds from issuance of convertible preferred stock					$ 37,100
Redeemable Convertible Series D Preferred Stock [Member] \| Rhythm xcience acquisition [Member]
Temporary Equity [Line Items]
Business combination contingent consideration shares issued shares			119,993
Business combination contingent consideration shares issued value			$ 2,200
Redeemable Convertible Series D Preferred Stock [Member] \| Biotonik Asset Acquisition [Member]
Temporary Equity [Line Items]
Business combination contingent consideration shares issued shares			273,070
Business combination contingent consideration shares issued value			$ 5,000
Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible preferred stock, shares authorized							172,064,796
Convertible preferred stock, par value							$ 0.001
Redeemable Convertible Series A Preferred Stock [Member] \| Non Cumulative Dividends [Member]
Temporary Equity [Line Items]
Temporary equity dividend per share declared						0.68
Redeemable Convertible Series B Preferred Stock [Member] \| Non Cumulative Dividends [Member]
Temporary Equity [Line Items]
Temporary equity dividend per share declared						1.07
Redeemable Convertible Series C Preferred Stock [Member] \| Non Cumulative Dividends [Member]
Temporary Equity [Line Items]
Temporary equity dividend per share declared						$ 1.36

Convertible Preferred Stock - S

Convertible Preferred Stock - Schedule of Initial Conversion Price Per Share for each Series of Convertible Preferred Stock (Detail)	Dec. 31, 2020$ / shares
Redeemable Convertible Series A Preferred Stock [Member]
Temporary Equity [Line Items]
Temporary equity initial conversion price per share	$ 8.295
Redeemable Convertible Series B Preferred Stock [Member]
Temporary Equity [Line Items]
Temporary equity initial conversion price per share	13.370
Redeemable Convertible Series C Preferred Stock [Member]
Temporary Equity [Line Items]
Temporary equity initial conversion price per share	16.667
Redeemable Convertible Series D Preferred Stock [Member]
Temporary Equity [Line Items]
Temporary equity initial conversion price per share	$ 16.667

Stockholders' Equity (Deficit)

Stockholders' Equity (Deficit) - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Aug. 10, 2020	Dec. 31, 2020	Dec. 31, 2019
Class Of Stock [Line Items]
Proceeds from issuance of common stock upon IPO, net of issuance costs		$ 166,286
Common Stock, Shares Authorized	260,000,000	260,000,000	220,000,000
Convertible Preferred Stock, Shares Authorized	5,000,000
Common Stock, Par or Stated Value Per Share		$ 0.001	$ 0.001
Common stock voting rights			one voting right
Proceeds from stock options exercises		$ 634	$ 108
Common Stock [Member]
Class Of Stock [Line Items]
Stock option exercises, shares		124,938	27,799
Amended and Restated Certificate of Incorporation [Member]
Class Of Stock [Line Items]
Common Stock, Shares Authorized			220,000,000
Common Stock, Par or Stated Value Per Share			$ 0.001
IPO [Member]
Class Of Stock [Line Items]
Number of shares issued during the period	10,147,058
Gross proceeds from IPO	$ 182,600
Proceeds from issuance of common stock upon IPO, net of issuance costs	$ 166,300
Over-Allotment Option [Member]
Class Of Stock [Line Items]
Number of shares issued during the period	1,323,529
IPO and Over Allotment [Member]
Class Of Stock [Line Items]
Price per share	$ 18

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Aug. 05, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Fair value exercise price to calculate aggregate intrinsic value of options		$ 28.81	$ 14.81	$ 11.91
Share based compensation by share based payment arrangement weighted-average grant date fair value per share of stock option grants		$ 11.58	$ 9.72
Unrecognized compensation related to stock options not vested		$ 28
Share based compensation non vested award period for recognition		2 years 9 months 18 days
Performance Based Restricted Stock Units [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share based compensation by share based payment arrangement instruments other than options granted	567,509	270,718	567,509
Share based compensation by share based payment arrangement instruments other than options granted weighted average grant date fair value	$ 13.37	$ 19.87	$ 13.37
2020 Equity Incentive Plan [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share based payment arrangement, shares authorized for issuance		2,193,360
Share based payment arrangement number of shares available for issuance		1,032,016
2011 Plan [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share based payment arrangement, shares authorized for issuance		2,764,600
Share based payment arrangement number of shares available for issuance		0
Share based compensation by share based payment arrangement stock options vesting term		4 years
Share based compensation by share based payment arrangement stock options contractual term		10 years
2020 ESPP [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share based payment arrangement, shares authorized for issuance					387,063
Share based payment arrangement, shares purchased		0

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Estimate of the Fair Value of Stock Option (Detail)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Share Based Payment Award Stock Options Valuation Assumptions [Line Items]
Risk-free interest rate, minimum	0.35%	1.60%
Risk-free interest rate, maximum	0.90%	2.10%
Expected term in years	7 years
Expected volatility		80.00%
Expected volatility, minimum	60.00%
Expected volatility, maximum	80.00%
Minimum [Member]
Schedule Of Share Based Payment Award Stock Options Valuation Assumptions [Line Items]
Expected term in years		6 years 4 months 24 days
Maximum [Member]
Schedule Of Share Based Payment Award Stock Options Valuation Assumptions [Line Items]
Expected term in years		10 years

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Detail) - Stock Option [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options outstanding beginning balance	2,041,205	1,587,410
Options granted	1,794,895	540,157
Options exercised	(172,312)	(27,806)
Options forfeited	(260,181)	(58,556)
Stock options outstanding ending balance	3,403,607	2,041,205	1,587,410
Stock options vested and exercisable as of December 31, 2020	1,403,764
Weighted average exercise price outstanding beginning balance	$ 9.52	$ 8.13
Options granted	16.91	13.37
Options exercised	7.52	3.87
Options forfeited	12.10	9.86
Weighted average exercise price outstanding ending balance	13.32	$ 9.52	$ 8.13
Weighted average exercise price of options vested and exercisable as of December 31, 2020	$ 9.55
Weighted average remaining contractual life outstanding	8 years 1 month 6 days	7 years 8 months 12 days	8 years
Weighted average remaining contractual life of options vested and exercisable as of December 31, 2020	6 years 7 months 6 days
Aggregate intrinsic value outstanding beginning balance	$ 10,782	$ 6,012
Aggregate intrinsic value, options exercised	1,660	251
Aggregate intrinsic value outstanding ending balance	52,866	$ 10,782	$ 6,012
Aggregate intrinsic value of options vested and exercisable as of December 31, 2020	$ 27,035

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of PSU and RSA Activity (Detail) - Performance Based Restricted Stock Units [Member] - $ / shares	1 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares Unvested Beginning Balance		567,509
Granted	567,509	270,718	567,509
Forfeited		(7,386)
Vested		(285,375)
Number of Shares Unvested Ending Balance		545,466	567,509
Weighted Average Grant Price Unvested Beginning Balance		$ 13.37
Granted	$ 13.37	19.87	$ 13.37
Forfeited		18
Vested		13.37
Weighted Average Grant Price Unvested Ending Balance		$ 16.53	$ 13.37

Stock-Based Compensation - Sc_3

Stock-Based Compensation - Schedule of RSA Activity (Detail) - Restricted Stock Awards [Member] - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Granted	34,051	11,449
Number of Shares, Vested	(34,051)	(11,449)
Weighted Average Grant Price, Granted	$ 16.85	$ 13.37
Weighted Average Grant Price, Vested	$ 16.85	$ 13.37

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of the Total Stock-Based Compensation Expense for the Stock Options, PSUs and RSAs Recorded in the Condensed Consolidated Statements of Operations and Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	$ 12,103	$ 2,994
Cost of Sales [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	440	209
Research and Development Expense [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	1,002	656
SG&A Expense [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation	$ 10,661	$ 2,129

Net Loss Per Common Share - Sum

Net Loss Per Common Share - Summary of Calculation of the Diluted Net Loss per Common Share (Detail) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares issuable	4,773,681	19,177,629
Conversion of Series A Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares issuable		391,210
Conversion of Series B Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares issuable		3,088,444
Conversion of Series C Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares issuable		4,499,921
Conversion of Series D Preferred Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares issuable		8,200,297
Exercise of Stock Options [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares issuable	3,403,607	2,041,205
Exercise of Common Stock Warrants [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares issuable	824,608	509,562
Exercise of Preferred Stock Warrants [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares issuable		446,990
Vesting of PSUs and RSUs [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares issuable	545,466

401(k) Retirement Plan - Additi

401(k) Retirement Plan - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Four Zero One K Retirement Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer contribution to defined benefit plan	$ 0	$ 0

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Pretax Loss From Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
U.S. domestic	$ (102,048)	$ (97,091)
Foreign	90	52
Pretax loss from operations	$ (101,958)	$ (97,039)

Income Taxes - Schedule of Co_2

Income Taxes - Schedule of Components of Income Tax Expense for Continuing Operations (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Current tax provision:
State	$ 23
Total provision for income taxes	$ 23

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
Income Taxes - Additional Information (Detail) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Line Items]
Provision for state income taxes	$ 23,000
Provision for federal, state or foreign income taxes	23,000	$ 0
Deferred tax assets, valuation allowance	$ 79,782,000	52,949,000
Federal NOLs to be carried back to offset previous years income term	5 years
NOLs carried forward to offset taxable income	100.00%
NOLs carried forward to offset taxable income for 2021 and thereafter	80.00%
Unrecognized tax benefits	$ 3,397,000	1,539,000	$ 1,523,000
Unrecognized tax benefits that, if recognized, would affect the effective tax rate	$ 3,100,000
Income tax examination, description	Since the Company formed in 2011, all filed tax returns are subject to examination. Generally, the tax years remain open for examination by the federal statute under a three-year statute of limitation; however, states generally keep their statutes open for four years. However, the Company’s tax years from inception are subject to examination by the United States and California taxing authorities due to the carry forward of unused NOLs and R&D credits.
Interest and penalties accrued	$ 0	0
Interest and/or penalties recognized	0	$ 0
Federal [Member]
Income Taxes [Line Items]
NOL carryforwards	$ 303,500,000
NOL carryforwards, expiration date	Dec. 31, 2031
NOL carryforwards, expiration year	2031
NOL carryforwards amount offset will not expire	$ 195,300,000
Tax years remain open for examination, statute of limitation term	3 years
Federal [Member] \| R&D Credit Carryforwards [Member]
Income Taxes [Line Items]
Tax credit carryforwards	$ 6,600,000
Tax credit carryforwards, expiration date	Dec. 31, 2031
Federal [Member] \| NOL Begin to Expire in 2031
Income Taxes [Line Items]
NOL carryforwards	$ 108,200,000
State [Member]
Income Taxes [Line Items]
NOL carryforwards	$ 74,900,000
NOL carryforwards, expiration date	Dec. 31, 2029
State [Member] \| California [Member]
Income Taxes [Line Items]
Tax years remain open for examination, statute of limitation term	4 years
State [Member] \| California [Member] \| R&D Credit Carryforwards [Member]
Income Taxes [Line Items]
Tax credit carryforwards	$ 4,800,000
Tax credit carryforwards, expiration description	The state R&D credits do not expire.
Foreign [Member]
Income Taxes [Line Items]
NOL carryforwards	$ 500,000
Foreign [Member] \| Belgium [Member]
Income Taxes [Line Items]
NOL carryforwards, expiration description	Belgium NOLs do not expire.
Maximum [Member]
Income Taxes [Line Items]
Provision for state income taxes	$ 100,000

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Expected Tax Computed at U.S. Statutory Federal Income Tax Rate to Total Expense for Income Taxes (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income tax benefit at federal statutory rate	$ (21,411,000)	$ (20,378,000)
Adjustments for tax effects of:
State taxes, net	(2,237,000)	(1,315,000)
Permanent adjustments	968,000	567,000
Interest expense		230,000
Warrants	1,167,000	253,000
Research and development credit	(5,870,000)	(53,000)
Unrecognized tax benefit	1,761,000	16,000
Valuation allowance	26,619,000	20,500,000
Rate change	(737,000)	223,000
Other	(237,000)	(43,000)
Income tax expense	$ 23,000	$ 0
Income tax benefit at federal statutory rate	21.00%	21.00%
Adjustments for tax effects of:
State taxes, net	2.19%	1.35%
Permanent adjustments	(0.95%)	(0.58%)
Interest expense	0.00%	(0.24%)
Warrants	(1.14%)	(0.26%)
Research and development credit	5.76%	0.05%
Unrecognized tax benefit	(1.73%)	(0.02%)
Valuation allowance	(26.11%)	(21.11%)
Rate change	0.72%	(0.23%)
Other	0.23%	0.19%
Income tax expense	(0.03%)

Income Taxes - Schedule of Co_3

Income Taxes - Schedule of Components of Company's Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Net operating losses	$ 68,727	$ 45,455
Stock-based compensation	1,225	720
Research and development credit	7,225	3,116
Accrued vacation	390	187
Accrued expenses	745	484
IRC 263A		239
Intangible assets	3,863	3,047
Lease liability	439	605
Other	196	153
Total gross deferred tax assets	82,810	54,006
Valuation allowance	(79,782)	(52,949)
Net deferred tax asset	3,028	1,057
Deferred tax liabilities:
Property and equipment	(1,979)	(450)
Prepaid expenses	(642)	(122)
Right of use assets	(349)	(485)
IRC 263A	(58)
Total deferred tax liabilities	$ (3,028)	$ (1,057)

Income Taxes - Schedule of Chan

Income Taxes - Schedule of Changes to Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Balance at beginning of year	$ 1,539	$ 1,523
Increases (decreases) related to prior year tax positions	1,210
Increases (decreases) related to prior year tax positions		(493)
Increases related to current year tax positions	648	509
Balance at end of year	$ 3,397	$ 1,539

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Stock-based compensation expense	$ 12,103,000	$ 2,994,000
Selling, General and Administrative Expenses [Member]
Related Party Transaction [Line Items]
Stock-based compensation expense	10,661,000	2,129,000
Former Director and Shareholder [Member] \| Patent Rights from Former Director and Shareholder [Member] \| Maximum [Member]
Related Party Transaction [Line Items]
Royalty expense	$ 100,000	100,000
Former Director and Shareholder [Member] \| Patent Rights from Former Director and Shareholder [Member] \| Royalty Expenses [Member]
Related Party Transaction [Line Items]
Royalty expense as a percentage of net sales	3.00%
Beneficial Customer [Member] \| Sales [Member]
Related Party Transaction [Line Items]
Revenue from related parties	$ 500,000	300,000
Director and the Chairman [Member] \| Selling, General and Administrative Expenses [Member] \| PSUs [Member]
Related Party Transaction [Line Items]
Stock-based compensation expense	4,600,000
Director and the Chairman [Member] \| Consulting Agreement [Member] \| Selling, General and Administrative Expenses [Member]
Related Party Transaction [Line Items]
Consulting fees incurred for related party	200,000	200,000
Officer [Member] \| Consulting Agreement [Member] \| Selling, General and Administrative Expenses [Member]
Related Party Transaction [Line Items]
Consulting fees incurred for related party		300,000
Current Director and Officer [Member] \| Consulting Agreement [Member] \| Selling, General and Administrative Expenses [Member]
Related Party Transaction [Line Items]
Consulting fees incurred for related party		400,000
Orbimed Royalty Oppurtunities Two LP and Deerfield Private Design Fund LP [Member] \| 2019 Credit Agreement [Member]
Related Party Transaction [Line Items]
Line of credit maximum borrowing capacity		70,000,000
Line of credit cumulative drawdowns till date	40,000,000	40,000,000
Interest expenses related party	$ 5,500,000	$ 21,400,000