0001140361-21-009989 | 10-K | XBRL Viewer

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Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2020	Mar. 19, 2021	Jun. 30, 2020
Cover [Abstract]
Entity Registrant Name	CHF Solutions, Inc.
Entity Central Index Key	0001506492
Current Fiscal Year End Date	--12-31
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 Address, State or Province	MN
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 8.3
Entity Common Stock, Shares Outstanding		6,531,942

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 14,437	$ 1,279
Accounts receivable	905	799
Inventories	2,957	1,797
Other current assets	237	161
Total current assets	18,536	4,036
Property, plant and equipment, net	1,200	991
Operating lease right-of-use asset, net	255	442
Other assets	21	133
TOTAL ASSETS	20,012	5,602
Current liabilities
Accounts payable	1,097	1,488
Accrued compensation	2,192	1,592
Current portion of operating lease liability	206	186
Current portion of finance lease liability	24	0
Other current liabilities	66	85
Total current liabilities	3,585	3,351
Operating lease liability	55	261
Finance lease liability	54	0
Total liabilities	3,694	3,612
Commitments and contingencies
Stockholders' equity
Preferred stock	0	0
Common stock as of December 31, 2020 and December 31, 2019, par value $0.0001 per share; authorized 100,000,000 shares, issued and outstanding 2,736,060 and 155,802, respectively	0	0
Additional paid-in capital	249,663	218,278
Accumulated other comprehensive income:
Foreign currency translation adjustment	(7)	1,214
Accumulated deficit	(233,338)	(217,502)
Total stockholders' equity	16,318	1,990
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	20,012	5,602
Series A Junior Participating Preferred Stock [Member]
Stockholders' equity
Preferred stock	0	0
Series F Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock	$ 0	$ 0

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	39,969,873	39,969,465
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	2,736,060	155,802
Common stock, shares outstanding (in shares)	2,736,060	155,802
Series A Junior Participating Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	30,000	30,000
Preferred stock, shares outstanding (in shares)	0	0
Series F Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	127	535
Preferred stock, shares issued (in shares)	127	535
Preferred stock, shares outstanding (in shares)	127	535

Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Consolidated Statements of Operations and Comprehensive Loss [Abstract]
Net sales	$ 7,441	$ 5,511
Costs and Expenses:
Cost of goods sold	3,384	2,660
Selling, general and administrative	17,417	16,285
Research and development	3,668	4,672
Total costs and expenses	24,469	23,617
Loss from operations	(17,028)	(18,106)
Realized foreign currency translation gain from dissolution of subsidiary	1,202	0
Other income (expense), net	(1)	0
Loss before income taxes	(15,827)	(18,106)
Income tax expense	(9)	(8)
Net loss	$ (15,836)	$ (18,114)
Basic and diluted loss per share (in dollars per share)	$ (10.67)	$ (278.90)
Weighted average shares outstanding - basic and diluted (in shares)	1,649	81
Other comprehensive loss:
Realized foreign currency translation gain from dissolution of subsidiary	$ (1,202)	$ 0
Unrealized foreign currency translation adjustment	(19)	(9)
Total comprehensive loss	$ (17,057)	$ (18,123)

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid in Capital [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Deficit [Member]	Total
Balance at Dec. 31, 2018	$ 0	$ 204,101	$ 1,223	$ (199,388)	$ 5,936
Balance (in shares) at Dec. 31, 2018	17,114
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	$ 0	0	0	(18,114)	(18,114)
Realized foreign currency translation gain from dissolution of subsidiary					0
Unrealized foreign currency translation adjustment	0	0	(9)	0	(9)
Stock-based compensation, net	$ 0	1,512	0	0	1,512
Stock-based compensation, net (in shares)	0
Issuance of common stock, net	$ 0	12,665	0	0	12,665
Issuance of common stock, net (in shares)	59,955
Conversion of preferred stock into common stock	$ 0	0	0	0	0
Conversion of preferred stock into common stock (in shares)	78,733
Balance at Dec. 31, 2019	$ 0	218,278	1,124	(217,502)	1,990
Balance (in shares) at Dec. 31, 2019	155,802
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	$ 0	0	0	(15,836)	(15,836)
Realized foreign currency translation gain from dissolution of subsidiary	0	0	(1,202)	0	(1,202)
Unrealized foreign currency translation adjustment	0	0	(19)	0	(19)
Stock-based compensation, net	$ 0	1,349	0	0	1,349
Stock-based compensation, net (in shares)	0
Issuance of common stock, net	$ 0	25,921	0	0	25,921
Issuance of common stock, net (in shares)	1,695,877
Exercise of warrants	$ 0	4,115	0	0	4,115
Exercise of warrants (in shares)	455,139
Conversion of preferred stock into common stock	$ 0	0	0	0	0
Conversion of preferred stock into common stock (in shares)	429,242
Balance at Dec. 31, 2020	$ 0	$ 249,663	$ (7)	$ (233,338)	$ 16,318
Balance (in shares) at Dec. 31, 2020	2,736,060

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating Activities:
Net loss	$ (15,836)	$ (18,114)
Adjustments to reconcile net loss to cash flows used in operating activities:
Depreciation and amortization	376	239
Stock-based compensation expense	1,349	1,512
Loss on disposal of property and equipment	40	0
Realized foreign currency translation gain from dissolution of subsidiary	(1,202)	0
Changes in operating assets and liabilities:
Accounts receivable	(106)	(13)
Inventories	(1,420)	(343)
Other current assets	(76)	42
Other assets and liabilities	112	18
Accounts payable and accrued compensation	191	292
Net cash used in operations	(16,572)	(16,367)
Investing activities:
Purchases of property and equipment	(298)	(490)
Proceeds from sale of property and equipment	31	0
Net cash used in investing activities	(267)	(490)
Financing activities:
Proceeds from public stock offerings, net	25,921	12,665
Proceeds from warrant exercises	4,115	0
Payments on finance lease liability	(20)	0
Net cash provided by financing activities	30,016	12,665
Effect of exchange rate changes on cash	(19)	(9)
Net increase (decrease) in cash and cash equivalents	13,158	(4,201)
Cash and cash equivalents - beginning of year	1,279	5,480
Cash and cash equivalents - end of year	14,437	1,279
Supplemental schedule of non-cash activities
Financing fees incurred for subsequent equity financing included in other assets and accounts payable	0	111
Inventory transferred to property, plant and equipment	260	204
Equipment acquired through finance lease liability	98	0
Supplemental cash flow information
Cash paid for income taxes	$ 10	$ 4

Nature of Business and Significant Accounting Policies

12 Months Ended

Dec. 31, 2020

Nature of Business and Significant Accounting Policies [Abstract]

Nature of Business and Significant Accounting Policies

Note 1—Nature of Business and Significant Accounting Policies

Nature of Business

CHF Solutions, Inc. (the “Company”) is a medical device company focused on developing, manufacturing and commercializing the Aquadex FlexFlow® and Aquadex SmartFlow™ systems (collectively, the “Aquadex System”) for ultrafiltration therapy. The Aquadex SmartFlow™ system is indicated for temporary (up to eight hours) or extended (longer than 8 hours in patients who require hospitalization) use in adult and pediatric patients weighing 20kg or more whose fluid overload is unresponsive to medical management, including diuretics. CHF Solutions, Inc. is a Delaware corporation headquartered in Minneapolis with wholly owned subsidiaries in Ireland and Delaware. The Company has been listed on Nasdaq since February 2012.

In August 2016, the Company acquired the business associated with the Aquadex System (the “Aquadex Business”) from a subsidiary of Baxter International, Inc. (“Baxter”), and refocused its strategy to fully devote its resources to the Aquadex Business.

On October 6, 2020, the Company’s stockholders approved a reverse split of its outstanding common stock at a ratio in the range of 1-for-5 to 1-for-30 and, on October 9, 2020, the board of directors approved a 1-for-30 reverse split of the Company’s outstanding common stock that became effective after trading on October 16, 2020. This reverse stock split did not change the par value of the Company’s common stock or the number of common or preferred shares authorized by the Company’s Fourth Amended and Restated Certificate of Incorporation, as amended. All share and per-share amounts have been retroactively adjusted to reflect the reverse stock splits for all periods presented.

Going Concern

The Company’s consolidated financial statements have been prepared and presented on a basis assuming it continues as a going concern. During the years ended December 31, 2020 and 2019, the Company incurred losses from operations and net cash outflows from operating activities as disclosed in the consolidated statements of operations and cash flows, respectively. At December 31, 2020, the Company had an accumulated deficit of $233.3 million and it expects to incur losses for the immediate future. To date, the Company has been funded by debt and equity financings, and although the Company believes that it will be able to successfully fund its operations, there can be no assurance that it will be able to do so or that it will ever operate profitably.

The Company became a revenue generating company after acquiring the Aquadex Business in August 2016. The Company expects to incur additional losses in the near-term as it grows the Aquadex Business, including investments in expanding its sales and marketing capabilities, purchasing inventory, manufacturing components, and complying with the requirements related to being a U.S. public company. To become and remain profitable, the Company must succeed in expanding the adoption and market acceptance of the Aquadex System. This will require the Company to succeed in training personnel at hospitals and effectively and efficiently manufacturing, marketing and distributing the Aquadex System and related components. There can be no assurance that the Company will succeed in these activities, and it may never generate revenues sufficient to achieve profitability.

During 2019, 2020 and through March 19, 2021, the Company closed on underwritten public equity offerings for aggregate net proceeds of approximately $57.7 million after deducting the underwriting discounts and commissions and other costs associated with the offerings (see Note 5 –Stockholders’ Equity and Note 14 – Subsequent Events). The Company will require additional funding to grow its Aquadex Business, which may not be available on terms favorable to the Company, or at all. The Company may receive those funds from the proceeds from future warrant exercises, issuances of equity securities, or other financing transactions.

The Company believes that its existing capital resources will be sufficient to support its operating plan through December 31, 2022. However, the Company may seek to raise additional capital to support its growth or other strategic initiatives through debt, equity or a combination thereof.

Basis of Presentation

The accompanying consolidated financial statements include the accounts of CHF Solutions, Inc. and its wholly-owned subsidiaries, CHF Solutions, LLC, Sunshine Heart Company Pty Ltd (through November 2020) and Sunshine Heart Ireland Limited. All intercompany accounts and transactions between consolidated entities have been eliminated. During the year ended December 31, 2020, the Company closed its Australian subsidiary and recognized a gain of $1.2 million on the dissolution of the entity, due to the recognition of previously unrealized foreign currency translation gains. This subsidiary represented an immaterial portion of our operations and the dissolution did not represent a strategic shift and therefore, is not presented as a discontinued operation.

Use of Estimates

The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts and disclosures in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates.

Cash and Cash Equivalents

Cash and cash equivalents consist of cash and term deposits with original maturities of three months or less. The carrying value of these instruments approximate fair value. The balances, at times, may exceed federally insured limits. The Company has not experienced any losses on its cash and cash equivalents.

Accounts Receivable

Accounts receivable are unsecured, recorded at net realizable value, and do not bear interest. The Company makes judgments as to its ability to collect outstanding receivables based upon significant patterns of collectability, historical experience, and managements’ evaluation of specific accounts and will provide an allowance for credit losses when collection becomes doubtful. The Company performs credit evaluations of its customers’ financial condition on an as-needed basis. Payment is generally due 30 days from the invoice date and accounts past 30 days are individually analyzed for collectability. When all collection efforts have been exhausted, the account is written off against the related allowance. To date the Company has not experienced any write-offs or significant deterioration of the aging of its accounts receivable, and therefore, no allowance for doubtful accounts was considered necessary as of December 31, 2020 or December 31, 2019. As of December 31, 2020, no customer represented over 10% of the accounts receivable balance. As of December 31, 2019, two customers represented 13% and 12% of the accounts receivable balance.

Inventories

Inventories are recorded as the lower of cost or net realizable value using the first-in, first-out method. Overhead is allocated to manufactured finished goods inventory based on the normal capacity of the Company’s production facilities. Abnormal amounts of overhead, if any, are expensed as incurred. Inventories consisted of the following as of December 31:

	2020		2019
Finished Goods	$	1,343	$	750
Work in Process		342		79
Raw Materials		1,272		968
Total	$	2,957	$	1,797

Other Current Assets

Other current assets represent prepayments and deposits made by the Company.

Property, Plant and Equipment

Property and equipment is stated at cost less accumulated depreciation. Depreciation is computed based upon the estimated useful lives of the respective assets. Leasehold improvements are amortized using the straight-line method over the shorter of the lease term or the estimated useful life of the assets. Repairs and maintenance costs are expensed as incurred. The cost and accumulated depreciation of property, plant and equipment retired, or otherwise disposed of are removed from the related accounts, and any residual values are charged to expense. Depreciation expense has been calculated using the following estimated useful lives:

Production Equipment	3-7 years
Office Furniture and Fixtures	3-5 years
Computer Software and Equipment	3-4 years
Loaners and demo equipment	1-5 years
Leasehold improvements	3-5 years

Depreciation expense was $376,000 and $239,000 for the years ended December 31, 2020, and 2019, respectively.

Property and equipment are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset group may not be recoverable. If the impairment tests indicate that the carrying value of the asset, or asset group is greater than the expected undiscounted cash flows to be generated by such asset or asset group, further analysis is performed to determine the fair value of the asset or asset group. To the extent the fair value of the asset or asset group is less than its carrying value, an impairment loss is recognized equal to the amount the fair value of the asset or asset group is exceeded by its carrying amount. Assets to be disposed of are carried at the lower of their carrying value or fair value less costs to sell. Considerable management judgment is necessary to estimate the fair value of assets or asset groups, and accordingly, actual results could vary significantly from such estimates.

The Company continues to report operating losses and negative cash flows from operations, both of which it considers to be indicators of potential impairment. Therefore, the Company evaluates its long-lived assets for potential impairment at each reporting period. The Company has concluded that its cash flows from the various long-lived assets are highly interrelated and, as a result, the Company consists of a single asset group. As the Company expects to continue incurring losses in the foreseeable future, the undiscounted cash flow step was bypassed and the Company proceeded to fair value the asset group. The Company has determined the fair value of the asset group using expected cash flows associated with its loaner units by considering sales prices for similar assets and by estimating future discounted cash flows expected from the units. For recently acquired assets within the asset group, primarily equipment, the Company determined the fair value based on the replacement cost. Because the Company consists of one asset group, consideration is also given to the relationship between the Company’s market capitalization and its carrying value to further support the Company’s determination of fair value. There have been no impairment losses recognized for the years ended December 31, 2020 or 2019.

Revenue Recognition

The Company recognizes revenue in accordance with Accounting Standards Codification (“ASC”), Topic 606, Revenue from Contracts with Customers. Accordingly, the Company recognizes revenue when its customers obtain control of its products or services, in an amount that reflects the consideration that the Company expects to receive in exchange for those goods and services. See Note 2 – Revenue Recognition, for additional disclosures. For the years ended December 31, 2020, and 2019, one customer represented 10.5% and 10.0% of net sales, respectively.

Foreign Currency Translation

Sales and expenses denominated in foreign currencies are translated at average exchange rates in effect throughout the year. Assets and liabilities of foreign operations are translated at period-end exchange rates with the impacts of foreign currency translation recognized to cumulative translation adjustment, a component of accumulated other comprehensive income. Foreign currency transactions gains and losses are included in other expense, net in the consolidated statements of operations and other comprehensive loss.

Stock-Based Compensation

The Company recognizes all share-based payments to employees and directors, including grants of stock options and common stock awards in the consolidated statement of operations and comprehensive loss as an operating expense based on their fair values as established at the grant date. Equity instruments issued to non-employees include common stock awards or warrants to purchase shares of our common stock. These common stock awards or warrants are either fully-vested and exercisable at the date of grant or vest over a certain period during which services are provided. The Company expenses the fair market value of fully vested awards at the time of grant, and of unvested awards over the period in which the related services are received

The Company computes the estimated fair values of stock options and warrants using the Black-Scholes option pricing model and market-based warrants using a Monte Carlo valuation model. Market price at the date of grant is used to calculate the fair value of restricted stock units and common stock awards.

Stock-based compensation expense is based on awards ultimately expected to vest and is reduced for estimated forfeitures except for market-based warrants which are expensed based on the grant date fair value regardless of whether the award vests. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates.

See Note 6- Stock-Based Compensation, for further information regarding the assumptions used to calculate the fair value of share-based compensation.

Income Taxes

Deferred income taxes are provided on a liability method, whereby deferred tax assets are recognized for deductible temporary differences and operating loss and tax credit carryforwards. Deferred tax liabilities are recognized for taxable temporary differences, which are the differences between the reported amounts of assets and liabilities and their tax bases. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion or all the deferred tax assets will not be realized. Deferred tax assets and liabilities are adjusted for the effects of changes in tax laws and rates on the date of enactment. The Company recognizes the financial statement benefit of a tax position only after determining that the relevant tax authority would more likely than not sustain the position following an audit. For tax positions meeting the more-likely-than-not threshold, the amount recognized in the consolidated financial statements is the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement with the relevant tax authority.

Loss per share

Basic loss per share is computed based on the net loss for each period divided by the weighted average number of common shares outstanding. The net loss allocable to common stockholders for the year ended December 31, 2020, reflects a $1.8 million increase for the net deemed dividend to preferred stockholders provided in connection with the close of the public offering of Series H Convertible Preferred Stock on January 28, 2020. This net deemed dividend includes $0.2 million that resulted from the subsequent reduction in the exercise of price of the warrants as a result of the March 2020 offering. The net loss allocable to common stockholders for the year ended December 31, 2019, reflects a $4.5 million increase for the net deemed dividend to preferred stockholders provided in connection with the close of the public offering of Series G Convertible Preferred Stock on March 12, 2019 (see Note 5 – Stockholders’ Equity), representing the intrinsic value of the shares at the time of issuance.

Diluted earnings per share is computed based on the net loss allocable to common stockholders for each period divided by the weighted average number of common shares outstanding, increased by the number of additional shares that would have been outstanding had the potentially dilutive common shares been issued, and reduced by the number of shares the Company could have repurchased from the proceeds from issuance of the potentially dilutive shares. Potentially dilutive shares of common stock include shares underlying outstanding convertible preferred stock, warrants, stock options and other stock-based awards granted under stock-based compensation plans.

The following table sets forth the potential shares of common stock that are not included in the calculation of diluted net loss per share because to do so would be anti-dilutive as of the end of each year presented:

	December 31,
	2020		2019
Stock options		16,889		13,471
Warrants to purchase common stock		1,631,948		231,629
Series F convertible preferred stock		14,224		18,190
Total		1,663,061		263,290

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2020			2019
Net loss	$	(15,836	)	$	(18,114	)
Deemed dividend to preferred stockholders (see Note 5)		(1,757	)		(4,509	)
Net loss after deemed dividend		(17,593	)		(22,623	)
Weighted average shares outstanding		1,649			81
Basic and diluted loss per share	$	(10.67	)	$	(278.90	)

Research and Development

Research and development costs include activities related to research, development, design, and testing improvements of the Aquadex System and potential related products. Research and development costs also include expenses related to clinical research that the Company may sponsor or conduct to enhance understanding of the product and its use. Research and development expenses are expensed as incurred.

Recent Accounting Pronouncements

The Company evaluates events through the date the consolidated financial statements are filed for events requiring adjustment to or disclosure in the consolidated financial statements. There are no new accounting pronouncements not yet adopted that the Company believes will have a material impact on its consolidated financial statements.

Revenue Recognition	12 Months Ended
Revenue Recognition	Dec. 31, 2020
Revenue Recognition [Abstract]
Revenue Recognition	Note 2 – Revenue Recognition Net Sales The Company sells its products in the United States primarily through a direct sales force. Customers who purchase the Company’s products include hospitals and clinics throughout the United States. In countries outside the United States, the Company sells its products through a limited number of specialty healthcare distributors in Austria, Brazil, Brunei, Germany, Greece, Hong Kong, India, Israel, Italy, Palestine, Singapore, Spain, Switzerland, Thailand and the United Kingdom. These distributors resell the Company’s products to hospitals and clinics in their respective geographies. Revenue from product sales are recognized when the customer or distributor obtains control of the product, which occurs at a point in time, most frequently upon shipment of the product or receipt of the product, depending on shipment terms. The Company’s standard shipping terms are FOB shipping point, unless the customer requests that control and title to the inventory transfer upon delivery. Revenue is measured as the amount of consideration we expect to receive, adjusted for any applicable estimates of variable consideration and other factors affecting the transaction price, which is based on the invoiced price, in exchange for transferring products. All revenue is recognized when the Company satisfies its performance obligations under the contract. The majority of the Company’s contracts have a single performance obligation and are short term in nature. The Company has entered into extended service plans with customers which are recognized over time. This revenue represents less than 1% of net sales for the years ended December 31, 2020 and 2019. The unfulfilled performance obligations related to these extended service plans is included in deferred revenue, which is included in other current liabilities on the consolidated balance sheets. The majority of the deferred revenue is expected to be recognized within one year. Sales taxes and value added taxes in foreign jurisdictions that are collected from customers and remitted to governmental authorities are accounted for on a net basis and therefore are excluded from net sales. Revenue includes shipment and handling fees charged to customers. Shipping and handling costs associated with outbound freight after control over a product has transferred to a customer are accounted for as a fulfillment cost and are included in cost of goods sold. Customers that are part of a group purchasing organization and have agreements with the Company receive administrative fees for purchases which are netted against revenues. Product Returns: The Company offers customers a limited right of return for its product in case of non-conformity or performance issues. The Company estimates the amount of its product sales that may be returned by its customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized. The Company currently estimates product return liabilities using available industry data and its own historical sales and returns information. The Company has not received any returns to date and believes that future returns of its products will be minimal. Therefore, revenue recognized is not currently impacted by variable consideration related to product returns.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 50
-Paragraph 12
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-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
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-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045

+ Details

Property, Plant and Equipment

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Note 3—Property, Plant and Equipment

Property, plant and equipment were as follows:

(in thousands)	December 31, 2020			December 31, 2019
Production Equipment	$	1,201		$	1,113
Loaners and Demo Equipment		1,073			801
Computer Software and Equipment		691			579
Office Furniture & Fixtures		364			291
Leasehold Improvements		242			224
Total		3,571			3,008
Accumulated Depreciation		(2,371	)		(2,017	)
	$	1,200		$	991

Debt	12 Months Ended
Debt	Dec. 31, 2020
Debt [Abstract]
Debt	Note 4—Debt On August 5, 2016, the Company entered into a loan and security agreement with Silicon Valley Bank (the Bank). Under this agreement, the Bank agreed to provide the Company with up to $5.0 million in debt financing, consisting of a term loan in an aggregate original principal amount not to exceed $4.0 million (the “Term Loan”) and a revolving line of credit in an aggregate principal amount not to exceed $1.0 million outstanding at any time (the “Revolving Line”). Proceeds from the loans were to be used for general corporate and working capital purposes. Advances under the Term Loan were available to the Company until November 30, 2016 and were subject to the Company’s compliance with liquidity covenants. The Term Loan expired unused on November 30, 2016 and is no longer available to be drawn. Advances under the Revolving Line were available to the Company until March 31, 2020 and were to accrue interest at a floating annual rate equal to 1.75% or 1.0% above the prime rate, depending on liquidity factors. Outstanding borrowings, if any, were to be collateralized by all of the Company’s assets, excluding intellectual property which was subject to a negative pledge. The Revolving Line expired unused on March 31, 2020. There were no borrowings outstanding under this facility as of December 31, 2019.

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2020
Stockholders' Equity [Abstract]
Stockholders' Equity	Note 5—Stockholders’ Equity Series F Convertible Preferred Stock: On November 27, 2017, the Company closed on an underwritten public offering Series F Convertible Preferred Stock and warrants to purchase shares of common stock for gross proceeds of $18.0 million. Net proceeds totaled approximately $16.2 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The offering was comprised of Series F convertible preferred stock, convertible into shares of the Company’s common stock at an initial conversion price of $1,890.00 per share. Each share of Series F convertible preferred stock was accompanied by a Series 1 warrant, which was to expire on the first anniversary of its issuance, to purchase 16 shares of the Company’s common stock at an exercise price of $1,890.00 per share, and a Series 2 warrant, which expires on the seventh anniversary of its issuance, to purchase 16 shares of the Company’s common stock at an exercise price of $1,890.00 per share. The Series F convertible preferred stock has full ratchet price based anti-dilution protection, subject to customary carve outs, in the event of a down-round financing at a price per share below the conversion price of the Series F convertible preferred stock (which protection will expire if, during any 20 of 30 consecutive trading days, the volume weighted average price of the Company’s common stock exceeds 300% of the then-effective conversion price of the Series F convertible preferred stock and the daily dollar trading volume for each trading day during such period exceeds $200,000). The exercise price of the warrants is fixed and does not contain any variable pricing features, nor any price based anti-dilutive features, apart from customary adjustments for stock splits, combinations, reclassifications, stock dividends or fundamental transactions. A total of 18,000 shares of Series F convertible preferred stock initially convertible into 9,557 shares of common stock and warrants to purchase 19,122 shares of common stock were issued in the offering. Effective March 12, 2019, the conversion price of the Series F convertible preferred stock was reduced from $890.40 to $157.50, the per share price to the public of the Series G convertible preferred stock issued in the March 2019 Offering, described below. Effective October 25, 2019, the conversion price of the Series F convertible preferred stock was reduced from $157.50 to $42.30, and on November 6, 2019 from $42.30 to $29.83, the per share price to the public in the October and November 2019 transactions, respectively, described below. Effective January 28, 2020, the conversion price of the Series F convertible preferred stock was reduced from $29.83 to $16.50, the per share price to the public of the Series H convertible preferred stock which closed in an underwritten public offering on January 28, 2020, described below. Effective March 23, 2020, the conversion price of the Series F convertible preferred stock was reduced from $16.50 to $9.00, the per share price to the public in the March 2020 transaction, described below. As of December 31, 2020, and December 31, 2019, 127 and 535 shares, respectively, of the Series F convertible preferred stock remained outstanding. Series G Convertible Preferred Stock and March 2019 Offering: On March 12, 2019, the Company closed on an underwritten public offering of common stock, Series G convertible preferred stock and warrants to purchase shares of common stock for gross proceeds of $12.4 million, which included the full exercise of the underwriter’s over-allotment option to purchase additional shares and warrants (“March 2019 Offering”). Net proceeds totaled approximately $11.0 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The Series G convertible preferred stock included a beneficial conversion amount of $4.5 million, representing the intrinsic value of the shares at the time of issuance. This amount is reflected as an increase to the loss per share allocable to common stockholders in the years ended December 31, 2019. The March 2019 Offering was comprised of 15,173 shares of common stock priced at $157.50 per share and 1,910,536 shares of Series G convertible preferred stock, convertible into common stock at $157.50 per share. Each share of Series G convertible preferred stock and each share of common stock was accompanied by a Series 1 warrant and a Series 2 warrant. The Series 1 warrants are exercisable into 78,863 shares of common stock and the Series 2 warrants are exercisable into 78,863 shares of common stock. Series 1 warrants expire on the fifth anniversary of the date of issuance and are exercisable at $157.50 to purchase one share of common stock. Series 2 warrants expire on the earlier of: (i) the eighteen-month anniversary of the date of issuance and (ii) the 30th trading day following the public announcement of the receipt from the U.S. Food and Drug Administration (FDA) of clearance or approval of a modification to the product label for the Aquadex System to include pediatric patients. Series 2 warrants are exercisable at $157.50 per share of common stock. The Company announced it had received FDA clearance for use of its Aquadex System in pediatric patients on February 26, 2020, effectively setting the date of expiration of these warrants for April 8, 2020. The conversion price of the Series G convertible preferred stock as well as the exercise price of the warrants are fixed and do not contain any variable pricing features, nor any price based anti-dilutive features apart from customary adjustments for splits and reverse splits of common stock. The Series G convertible preferred stock included a beneficial ownership limitation of 4.99% but had no dividend preference (except to extent dividends are also paid on the common stock), liquidation preference or other preferences over common stock. The securities comprising the units were immediately separable and were issued separately. As of December 31, 2019, all 63,685 shares of the Series G convertible preferred stock had been converted into common stock and none remained outstanding. October and November 2019 Offerings: On October 25, 2019, the Company closed on a registered direct offering of 19,195 shares of common stock at a price of $34.50 per share, for gross proceeds of approximately $660,000, prior to deducting commissions and expenses related to the transaction. In a concurrent private placement, the Company agreed to issue to the investors in the registered direct offering unregistered warrants to purchase up to 19,196 shares of its common stock at an exercise price of $42.30 per share, which became exercisable six months from the date of issuance and will expire five years from the initial exercise date. On November 6, 2019, the Company closed on a registered direct offering of 40,637 shares of common stock, or common equivalents, at a price of $33.60 per share, for gross proceeds of approximately $1.36 million prior to deduction of commissions and offering expenses related to the transaction. In a concurrent private placement, the Company agreed to issue to the investors in the registered direct offering warrants to purchase up to 40,638 shares of our common stock at an exercise price of $29.83 per share, which were exercisable upon the date of issuance, and will expire five years from the initial exercise date. Series H Convertible Preferred Stock and January 2020 Offering: On January 28, 2020, the Company closed on an underwritten public offering of common stock, Series H convertible preferred stock and warrants to purchase shares of common stock for gross proceeds of $9.7 million, which included the full exercise of the underwriter’s over-allotment option to purchase additional shares and warrants (“January 2020 Offering”). Net proceeds totaled approximately $8.6 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The Series H convertible preferred stock included a beneficial conversion amount of $1.6 million, representing the intrinsic value of the shares at the time of issuance, and $0.2 million of down-round protection in connection with the re-pricing of the warrants following the March 2020 offering described below. This amount is reflected as an increase to the loss per share allocable to common stockholders in the year ended December 31, 2020. The January 2020 Offering was comprised of 201,546 shares of common stock priced at $16.50 per share and 11,517,269 shares of Series H convertible preferred stock, convertible into common stock at $16.50 per share, including the full exercise of the over-allotment option. Each share of Series H convertible preferred stock and each share of common stock was accompanied by a warrant to purchase common stock. The warrants are exercisable into 585,460 shares of common stock. The conversion price of the preferred stock issued in the transaction is fixed and does not contain any variable pricing feature or any price based anti-dilutive feature. The preferred stock issued in this transaction includes a beneficial ownership blocker but has no dividend rights (except to the extent that dividends are also paid on the common stock) or liquidation preference, and, subject to limited exceptions, has no voting rights. The securities comprising the units are immediately separable and were issued separately. The warrants were exercisable beginning on the closing date and expire on the fifth anniversary of the closing date and had an initial exercise price per share equal to $16.50 per share, subject to appropriate adjustment in the event of subsequent equity sales of common stock or securities convertible into common stock for an exercise price per share less than the exercise price per share of the warrants then in effect (but in no event lower than 10% of the applicable Unit offering price), or in the event of recapitalization events, stock dividends, stock splits, stock combinations, reclassifications, reorganizations or similar events affecting our common stock. Effective March 23, 2020, the exercise price of these warrants was reduced from $16.50 to $9.00, the per share price to the public in the March 2020 offering, described below. As of December 31, 2020, all 11,517,269 shares of the Series H convertible preferred stock had been converted into common stock and none remained outstanding. As of December 31, 2020, warrants to purchase 455,162 shares of common stock had been exercised for total cash proceeds of $4.1 million. March 2020 Offering: On March 23, 2020, the Company closed on a registered direct offering of 138,715 shares of its common stock at a price to the public of $9.00 per share, for gross proceeds of approximately $1.2 million, or $1.0 million net after deducting commissions and offering expenses payable by CHF Solutions. In a concurrent private placement, the Company agreed to issue to the investors in the registered direct offering warrants to purchase up to 138,715 shares of the Company’s common stock. The warrants to purchase up to 138,715 shares of common stock have an exercise price of $11.18 per share, were exercisable six months from the date of issuance, and will expire five and a half years from the date of issuance. April 2020 Offering: On April 1, 2020 the Company closed on a registered direct offering of 171,008 shares of its common stock at a price to the public of $13.02 per share, for gross proceeds of approximately $2.2 million, prior to deduction of commissions and offering expenses related to the transaction. In a concurrent private placement, the Company agreed to issue to the investors in the registered direct offering warrants to purchase up to 85,506 shares of the Company’s common stock. The warrants have an exercise price of $11.15 per share, were exercisable immediately, and will expire five and a half years from the date of issuance. May 2020 Offering: On May 5, 2020 the Company closed on a registered direct offering of 119,930 shares of its common stock at a price to the public of $14.18 per share, for gross proceeds of approximately $1.7 million, prior to deduction of commissions and offering expenses related to the transaction. In a concurrent private placement, the Company agreed to issue to the investors in the registered direct offering warrants to purchase up to 59,966 shares of the Company’s common stock. The warrants have an exercise price of $12.30 per share, were exercisable immediately, and will expire five and a half years from the date of issuance. August 2020 Offering: On August 21, 2020, the Company closed on an underwritten public offering of common stock and warrants to purchase shares of common stock for gross proceeds of approximately $14.4 million, which included the full exercise of the underwriter’s over-allotment option to purchase additional shares and warrants (“August 2020 Offering”). Net proceeds totaled approximately $13.0 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The August 2020 Offering was comprised of 1,064,678 shares of common stock priced at $13.50 per share. Each share of common stock was accompanied by a warrant to purchase common stock. The warrants are exercisable into 1,064,678 shares of common stock. The securities comprising the units are immediately separable and were issued separately. The warrants were exercisable beginning on the effective date of our stockholders’ approval of a reverse stock split in an amount sufficient to permit the exercise in full of the warrants, which occurred on October 6, 2020, and will expire on the five-year anniversary of the closing date. Placement Agent Fees: In connection with the offerings described above, the Company paid the placement agents an aggregate cash placement fee equal to 8% of the aggregate gross proceeds raised in each of the offerings. Market-Based Warrants: On May 30, 2019, the Company granted a market-based warrant to a consultant in exchange for investor relations services. The warrant represents the right to acquire up to 3,334 shares of the Company’s common stock at an exercise price of $95.40 per share, the closing stock price of the Company’s common shares on May 30, 2019. The warrant is subject to a vesting schedule based on the Company achieving certain market stock prices within a specified period of time. The warrant expires on May 30, 2024. The warrant was valued at $57.90 per share using the Monte Carlo valuation methodology and was expensed over the term of the consulting engagement which was twelve months. Significant inputs used for the Monte Carlo valuation were the expected stock price volatility of 136.21%, and management’s expectations regarding the timing of regulatory clearance for an expanded label in pediatrics. None of these warrants had vested as of December 31, 2020.

Stock-Based Compensation

12 Months Ended

Dec. 31, 2020

Stock-Based Compensation [Abstract]

Stock-Based Compensation

Note 6— Stock-Based Compensation

Stock Options and Restricted Stock Awards

The Company has various share-based compensation plans, including the Amended and Restated 2002 Stock Plan, the Third Amended and Restated 2017 Equity Incentive Plan, the 2013 Non-Employee Directors’ Equity Incentive Plan and the New-Hire Equity Incentive Plan (collectively, the “Plans”). The Plans are designed to assist in attracting, motivating and retaining employees and directors and to recognize the importance of employees to the long-term performance and success of the Company. The Company has also granted stock options to certain non-employees outside of the Plans.

The Company recognized stock-based compensation expense related to grants of stock options, RSUs and common stock awards to employees, directors and consultants of $1.3 million, and $1.5 million during the years ended December 31, 2020 and 2019, respectively. The following table summarizes the stock-based compensation expense which was recognized in the consolidated statements of operations for the years ended December 31,

(Dollars in thousands)	2020		2019
Selling, general and administrative	$	1,252	$	1,387
Research and development		97		125
Total	$	1,349	$	1,512

The majority of the RSUs and options to purchase common stock vest on the anniversary of the date of grant, which ranges from one to four years. Stock-based compensation expense related to these awards is recognized on a straight-line basis over the related vesting term in most cases, which generally is the service period. It is the Company’s policy to issue new shares upon the exercise of options.

Stock Options: The following is a summary of the Plans’ stock option activity during the years ended December 31:

	2020					2019
	Options Outstanding			Weighted Average Exercise Price		Options Outstanding			Weighted Average Exercise Price
Beginning Balance		13,471		$	515.33		4,638		$	1,461.24
Granted		5,542			10.03		9,374			71.40
Exercised		—			—		—			—
Forfeited/expired		(2,124	)		71.51		(541	)		926.31
Outstanding at December 31		16,889		$	405.34		13,471		$	515.33
Vested at December 31		7,254		$	697.37		2,383		$	1,417.42

For options outstanding and vested at December 31, 2020, the weighted average remaining contractual life was 8.47 years and 8.07 years, respectively. There were no option exercises in 2020 or 2019. The total fair value of options that vested in 2020 and 2019 was $1.7 million, and $2.4 million, respectively, at the fair value of the options as of the date of grant.

Valuation Assumptions: The fair value of each stock option is estimated at the grant date using the Black-Scholes option pricing model. The fair value of stock options under the Black-Scholes option pricing model requires management to make assumptions regarding projected employee stock option exercise behaviors, risk-free interest rates, volatility of the Company’s stock price, and expected dividends.

The Company has not historically paid cash dividends to its stockholders, and currently does not anticipate paying any cash dividends in the foreseeable future. As a result, the Company has assumed a dividend yield of 0%. The risk-free interest rate is based upon the rates of U.S. Treasury bills with a term that approximates the expected life of the option. Since the Company has limited historical exercise data to reasonably estimate the expected life of its option awards, the expected life is calculated using a simplified method. Expected volatility is based on historical volatility of the Company’s stock.

The following table provides the weighted average assumptions used in the Black-Scholes option pricing model for the years ended December 31:

	2020			2019
Expected dividend yield		0	%		0	%
Risk-free interest rate		0.65	%		1.85	%
Expected volatility		127.87	%		121.67	%
Expected life (in years)		5.91			6.22

The weighted-average fair value of stock options granted in 2020 and 2019 was $8.79 and $62.37, respectively. As of December 31, 2020, the total compensation cost related to all non-vested stock option awards not yet recognized was approximately $1.5 million and is expected to be recognized over the remaining weighted-average period of 2.53 years.

Warrants

Warrants to purchase 1,631,948 and 231,629 shares of common stock were outstanding at December 31, 2020 and 2019, respectively. As of December 31, 2020, warrants outstanding were exercisable at prices ranging from $9.00 to $53,550 per share, and are exercisable over a period ranging from 10 months to 4.9 years.

Fair Value of Financial Instruments

12 Months Ended

Dec. 31, 2020

Fair Value of Financial Instruments [Abstract]

Fair Value of Financial Instruments

Note 7 - Fair Value of Financial Instruments

The Company’s financial instruments consist of cash and cash equivalents and warrants.

Pursuant to the requirements of ASC Topic 820 “Fair Value Measurement,” the Company’s financial assets and liabilities measured at fair value on a recurring basis are classified and disclosed in one of the following three categories:

•	Level 1 - Financial instruments with unadjusted quoted prices listed on active market exchanges.

•

Level 2 - Financial instruments lacking unadjusted, quoted prices from active market exchanges, including over the counter traded financial instruments. The prices for the financial instruments are determined using prices for recently traded financial instruments with similar underlying terms as well as directly or indirectly observable inputs, such as interest rates and yield curves that are observable at commonly quoted intervals.

•	Level 3 - Financial instruments that are not actively traded on a market exchange. This category includes situations where there is little, if any, market activity for the financial instrument. The prices are determined using significant unobservable inputs or valuation techniques.

The fair value of the market-based warrants described in Note 5 was calculated using a Monte Carlo valuation model and was classified as Level 3 in the fair value hierarchy. These warrants were classified as permanent equity and as a result, were measured at the grant date and are not required to be remeasured to fair value at each reporting period end.

All cash equivalents are considered Level 1 measurements for all periods presented. The Company does not have any financial instruments classified as Level 2 or Level 3 and there were no movements between these categories as of December

31, 2020 and December 31, 2019. The Company believes that the carrying amounts of all remaining financial instruments approximate their fair value due to their relatively short maturities.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Income Taxes

12 Months Ended

Dec. 31, 2020

Income Taxes [Abstract]

Income Taxes

Note 8—Income Taxes

Domestic and foreign loss before income taxes, consists of the following for the years ended December 31:

(in thousands)	2020			2019
Domestic	$	(15,865	)	$	(18,114	)
Foreign		38			8
Loss before income taxes	$	(15,827	)	$	(18,106	)

The components of income tax expense consist of the following for the years ended December 31:

(in thousands)	2020			2019
Current:
United States and state	$	—		$	—
Foreign, net		(9	)		(8	)
Deferred:
United States and state		—			—
Foreign		—			—
Total income tax expense	$	(9	)	$	(8	)

Actual income tax expense differs from statutory federal income tax expense as follows for the years ended December 31:

(in thousands)	2020			2019
Statutory federal income tax benefit	$	3,324		$	3,802
State tax benefit, net of federal taxes		94			46
Foreign tax		(1	)		1
Foreign deferred exchange rate adjustments		1,027			(59	)
Dissolution of foreign subsidiary		(11,401	)		—
Nondeductible/nontaxable items		34			(272	)
Other		(255	)		(113	)
Valuation allowance (increase) decrease		7,169			(3,413	)
Total income tax expense	$	(9	)	$	(8	)

Deferred taxes consist of the following as of December 31:

(in thousands)	2020			2019
Deferred tax assets:
Noncurrent:
Accrued leave	$	61		$	51
Other accrued expenses		—			—
Stock based compensation		293			449
Net operating loss carryforward		37,665			44,572
Other		11			69
Intangibles		751			809
R&D credit carryforward		531			531
Total deferred tax assets		39,312			46,481
Less: valuation allowance		(39,312	)		(46,481	)
Total	$	—		$	—

As of December 31, 2020, the Company had federal net operating loss (“NOLs”) carryforwards of approximately $168.2 million and $30.9 million of state NOL carryforwards. Approximately $120.1 million of federal NOL carryforwards will expire between 2024 and 2037. Pursuant to the Tax Cuts and Jobs Act of 2017, NOLs generated after 2017 of approximately $48.1 million do not expire. The expiration of state NOL carryforwards will vary by jurisdiction. In addition, future utilization of NOL carryforwards in the U.S. may be subject to certain limitations under Section 382 of the Internal Revenue Code. As of December 31, 2020, the Company no longer has tax loss carryforwards in the Commonwealth of Australia due to the dissolution of the subsidiary in November 2020.

The Company provides for a valuation allowance when it is more likely than not that it will not realize a portion of the deferred tax assets. The Company has established a valuation allowance for U.S. and foreign deferred tax assets due to the uncertainty that enough taxable income will be generated in those taxing jurisdictions to utilize the assets. Therefore, the Company has not reflected any benefit of such deferred tax assets in the accompanying consolidated financial statements. For the years ended December 31, 2020, and 2019, the valuation allowance decreased by $7.2 million and increased by $3.4 million, respectively. The current year decrease was primarily due to the dissolution of the Australian subsidiary and corresponding elimination of their net operating loss carryforwards previously subject to a valuation allowance.

During 2018, 2019 and 2020, the Company believes it experienced an ownership change as defined in Section 382 of the Internal Revenue Code which will limit the ability to utilize the Company’s net operating losses (NOLs). The Company may have experienced additional ownership changes in earlier years further limiting the NOL carry-forwards that may be utilized. The Company has not yet completed a formal Section 382 analysis. The general limitation rules allow the Company to utilize its NOLs subject to an annual limitation that is determined by multiplying the federal long-term tax-exempt rate by the Company’s value immediately before the ownership change.

The accounting guidance related to uncertain tax positions prescribes a recognition threshold and measurement attribute for recognition and measurement of a tax position taken or expected to be taken in a tax return. It also provides guidance on de-recognition, classification, interest and penalties, accounting in interim periods, disclosure and transition. The Company had no material uncertain tax positions as of December 31, 2020 or 2019.

The Company recognizes interest and penalties on unrecognized tax benefits as well as interest received from favorable tax settlements within income tax expense. At December 31, 2020 and 2019, the Company recorded no accrued interest or penalties related to uncertain tax positions.

The tax years ended December 31, 2017 through December 31, 2020 remain open to examination by the Internal Revenue Service and for the various states where the Company is subject to taxation. Additionally, the returns of the Company’s Australian (through November 2020) and Irish subsidiary are subject to examination by tax authorities of those jurisdictions for the tax years ended and subsequent to June 30, 2015 and December 31, 2015, respectively.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References + Details

Operating Leases

12 Months Ended

Dec. 31, 2020

Operating Leases [Abstract]

Operating Leases

Note 9—Operating Leases

The Company leases office and manufacturing space under a non-cancelable operating lease that expires in March 2022. In August 2018, the Company entered into a third amendment to the lease, extending the term of the lease from March 31, 2019 to March 31, 2022. Beginning on April 1, 2019, the annual base rent is $9.00 per square foot, subject to annual increases of $0.25 per square foot.

The cost components of the Company’s operating lease were as follows for the year ended December 31, :

(in thousands)
	2020		2019
Operating lease cost	$	213	$	213
Variable lease cost		114		102
Total	$	327	$	315

Variable lease costs consist primarily of taxes, insurance, and common area or other maintenance costs for our leased office and manufacturing space.

Maturities of our lease liability for the Company’s operating lease are as follows as of December 31, :

(in thousands)	2020
2021	$	219
2022		55
Total lease payments		274
Less: Interest		(13	)
Present value of lease liability	$	261

As of December 31, 2020, and 2019 the remaining lease terms were 1.25 and 2.25 years, respectively, and discount rates were 7.5% for each year. For the years ended December 31, 2020, and 2019 the operating cash outflows from the Company’s operating lease for office and manufacturing space were $213,000 and $206,000, respectively.

Finance Lease Liability	12 Months Ended
Finance Lease Liability	Dec. 31, 2020
Finance Lease Liability [Abstract]
Finance Lease Liability	Note 10—Finance Lease Liability In 2020, the Company entered into lease agreements to finance equipment valued at $98,000. The equipment consisted of computer hardware and audio-visual equipment and is included in Property, Plant and Equipment in the accompanying consolidated financial statements. The principal amount under the lease agreements was $93,000 at the date the lease commenced, the implied interest rate is 7.5%, and the term of the lease is 39 months.

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2020
Commitments and Contingencies [Abstract]
Commitments and Contingencies	Note 11—Commitments and Contingencies Employee Retirement Plan The Company has a 401(k)-profit sharing plan that provides retirement benefit to substantially all full-time U.S. employees. Eligible employees may contribute a percentage of their annual compensation, subject to Internal Revenue Service limitations, with the Company matching a portion of the employee’s contributions at the discretion of the Company. Matching contributions totaled $234,000 and $227,000 for the years ended December 31, 2020 and 2019, respectively. Contingent Consideration In connection with the Company’s purchase of the Aquadex Business in August 2016, the Company had an obligation to pay additional consideration that was contingent upon the occurrence of certain future events. Contingent consideration was recognized at the acquisition date at $126,000, the estimated fair value of the contingent milestone payments. The fair value of the contingent consideration was remeasured to its estimated fair value at the end of each reporting period, with changes recorded to earnings. During 2019, this contingency had expired, therefore its fair value was $0.

Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions	Note 12—Related Party Transactions In January 2019, we entered into a consulting agreement with Steven Brandt, one of our non-employee directors, pursuant to which Mr. Brandt provided services, on an interim basis, until May 31, 2019, to support our commercial strategy under the direction of our Chief Executive Officer. Mr. Brandt was paid a fee of $19,000 per month, for a total of $76,000 for his services. Mr. Brandt also received $2,453 for reimbursement of expenses. There were no related party transactions requiring disclosure during the year ended December 31, 2020.

Segment and Geographic Information	12 Months Ended
Segment and Geographic Information	Dec. 31, 2020
Segment and Geographic Information [Abstract]
Segment and Geographic Information	Note 13—Segment and Geographic Information The Company has one reportable segment, cardiac and coronary disease products. At December 31, 2019 and 2018, long-lived assets were located primarily in the United States.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8924-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	Note 14 – Subsequent Events On January 19, 2021, the Company announced that Nestor Jaramillo, Jr. was appointed as Chief Executive Officer and President of the Company. In connection with such appointment, he entered into an Executive Employment Agreement with the Company. Mr. Jaramillo had served as the Company’s chief operating officer and president since June 2020 and as the Company’s chief commercial officer from May 2019 to June 2020. John Erb, the predecessor Chief Executive Officer will remain a part-time employee for a period of six months to assist with the transition and thereafter will continue to serve as the Company’s Chairman of the Board. On March 19, 2021, the Company closed on an underwritten public offering of 3,795,816 shares of common stock, which includes the full exercise of the underwriter’s over-allotment option, for gross proceeds of approximately $20.9 million. Net proceeds totaled approximately $19.0 million after deducting the underwriting discounts and commissions and other costs associated with the offering and after giving effect to the underwriters’ full exercise of their overallotment option. In connection with this transaction, the conversion price of the Series F convertible preferred stock was reduced from $9.00 to $5.50, the per share price to the public in the March 2021 transaction, described above. In addition, the exercise price of the common stock warrants issued in connection with the January 2020 Offering was reduced from $9.00 to $5.50, the per share price to the public in the March 2021 offering, described above.

Nature of Business and Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2020

Nature of Business and Significant Accounting Policies [Abstract]

Going Concern

Basis of Presentation

Use of Estimates

Cash and Cash Equivalents

Accounts Receivable

Inventories

	2020		2019
Finished Goods	$	1,343	$	750
Work in Process		342		79
Raw Materials		1,272		968
Total	$	2,957	$	1,797

Other Current Assets

Other current assets represent prepayments and deposits made by the Company.

Property, Plant and Equipment

Production Equipment	3-7 years
Office Furniture and Fixtures	3-5 years
Computer Software and Equipment	3-4 years
Loaners and demo equipment	1-5 years
Leasehold improvements	3-5 years

Depreciation expense was $376,000 and $239,000 for the years ended December 31, 2020, and 2019, respectively.

Revenue Recognition

Foreign Currency Translation

Stock-Based Compensation

See Note 6- Stock-Based Compensation, for further information regarding the assumptions used to calculate the fair value of share-based compensation.

Income Taxes

Loss per Share

Loss per share

	December 31,
	2020		2019
Stock options		16,889		13,471
Warrants to purchase common stock		1,631,948		231,629
Series F convertible preferred stock		14,224		18,190
Total		1,663,061		263,290

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2020			2019
Net loss	$	(15,836	)	$	(18,114	)
Deemed dividend to preferred stockholders (see Note 5)		(1,757	)		(4,509	)
Net loss after deemed dividend		(17,593	)		(22,623	)
Weighted average shares outstanding		1,649			81
Basic and diluted loss per share	$	(10.67	)	$	(278.90	)

Research and Development

Recent Accounting Pronouncements

Nature of Business and Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2020

Nature of Business and Significant Accounting Policies [Abstract]

Inventories

Inventories consisted of the following as of December 31:

	2020		2019
Finished Goods	$	1,343	$	750
Work in Process		342		79
Raw Materials		1,272		968
Total	$	2,957	$	1,797

Estimated Useful Lives

Depreciation expense has been calculated using the following estimated useful lives:

Production Equipment	3-7 years
Office Furniture and Fixtures	3-5 years
Computer Software and Equipment	3-4 years
Loaners and demo equipment	1-5 years
Leasehold improvements	3-5 years

Potential Shares of Common Stock not Included in Diluted Net Loss Per Share

	December 31,
	2020		2019
Stock options		16,889		13,471
Warrants to purchase common stock		1,631,948		231,629
Series F convertible preferred stock		14,224		18,190
Total		1,663,061		263,290

Reconciles Reported Net Loss with Reported Net Loss Per Share

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2020			2019
Net loss	$	(15,836	)	$	(18,114	)
Deemed dividend to preferred stockholders (see Note 5)		(1,757	)		(4,509	)
Net loss after deemed dividend		(17,593	)		(22,623	)
Weighted average shares outstanding		1,649			81
Basic and diluted loss per share	$	(10.67	)	$	(278.90	)

Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Property, plant and equipment were as follows:

(in thousands)	December 31, 2020			December 31, 2019
Production Equipment	$	1,201		$	1,113
Loaners and Demo Equipment		1,073			801
Computer Software and Equipment		691			579
Office Furniture & Fixtures		364			291
Leasehold Improvements		242			224
Total		3,571			3,008
Accumulated Depreciation		(2,371	)		(2,017	)
	$	1,200		$	991

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2020

Stock-Based Compensation [Abstract]

Summary of Stock-Based Compensation Expense

The following table summarizes the stock-based compensation expense which was recognized in the consolidated statements of operations for the years ended December 31,

(Dollars in thousands)	2020		2019
Selling, general and administrative	$	1,252	$	1,387
Research and development		97		125
Total	$	1,349	$	1,512

Summary of Plan Stock Option Activity

The following is a summary of the Plans’ stock option activity during the years ended December 31:

	2020					2019
	Options Outstanding			Weighted Average Exercise Price		Options Outstanding			Weighted Average Exercise Price
Beginning Balance		13,471		$	515.33		4,638		$	1,461.24
Granted		5,542			10.03		9,374			71.40
Exercised		—			—		—			—
Forfeited/expired		(2,124	)		71.51		(541	)		926.31
Outstanding at December 31		16,889		$	405.34		13,471		$	515.33
Vested at December 31		7,254		$	697.37		2,383		$	1,417.42

Weighted Average Assumptions used in Black-Scholes Option Pricing Model

The following table provides the weighted average assumptions used in the Black-Scholes option pricing model for the years ended December 31:

	2020			2019
Expected dividend yield		0	%		0	%
Risk-free interest rate		0.65	%		1.85	%
Expected volatility		127.87	%		121.67	%
Expected life (in years)		5.91			6.22

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Income Taxes [Abstract]

Domestic and Foreign Loss Before Income Taxes

Domestic and foreign loss before income taxes, consists of the following for the years ended December 31:

(in thousands)	2020			2019
Domestic	$	(15,865	)	$	(18,114	)
Foreign		38			8
Loss before income taxes	$	(15,827	)	$	(18,106	)

Components of Income Tax Expense

The components of income tax expense consist of the following for the years ended December 31:

(in thousands)	2020			2019
Current:
United States and state	$	—		$	—
Foreign, net		(9	)		(8	)
Deferred:
United States and state		—			—
Foreign		—			—
Total income tax expense	$	(9	)	$	(8	)

Actual Income Tax Expense Differs from Statutory Federal Income Tax Expense

Actual income tax expense differs from statutory federal income tax expense as follows for the years ended December 31:

(in thousands)	2020			2019
Statutory federal income tax benefit	$	3,324		$	3,802
State tax benefit, net of federal taxes		94			46
Foreign tax		(1	)		1
Foreign deferred exchange rate adjustments		1,027			(59	)
Dissolution of foreign subsidiary		(11,401	)		—
Nondeductible/nontaxable items		34			(272	)
Other		(255	)		(113	)
Valuation allowance (increase) decrease		7,169			(3,413	)
Total income tax expense	$	(9	)	$	(8	)

Deferred Taxes

Deferred taxes consist of the following as of December 31:

(in thousands)	2020			2019
Deferred tax assets:
Noncurrent:
Accrued leave	$	61		$	51
Other accrued expenses		—			—
Stock based compensation		293			449
Net operating loss carryforward		37,665			44,572
Other		11			69
Intangibles		751			809
R&D credit carryforward		531			531
Total deferred tax assets		39,312			46,481
Less: valuation allowance		(39,312	)		(46,481	)
Total	$	—		$	—

Operating Leases (Tables)

12 Months Ended

Dec. 31, 2020

Operating Leases [Abstract]

Cost Components of Operating Leases

The cost components of the Company’s operating lease were as follows for the year ended December 31, :

(in thousands)
	2020		2019
Operating lease cost	$	213	$	213
Variable lease cost		114		102
Total	$	327	$	315

Maturities of Lease Liability

Maturities of our lease liability for the Company’s operating lease are as follows as of December 31, :

(in thousands)	2020
2021	$	219
2022		55
Total lease payments		274
Less: Interest		(13	)
Present value of lease liability	$	261

Nature of Business and Significant Accounting Policies, Nature of Business, Going Concern, Basis of Presentation, Accounts Receivable and Inventories (Details) $ in Thousands			12 Months Ended
	Oct. 09, 2020	Oct. 06, 2020	Dec. 31, 2020 USD ($) Customer	Dec. 31, 2019 USD ($) Customer	Mar. 19, 2021 USD ($)
Nature of Business [Abstract]
Reverse stock split ratio	0.033
Going Concern [Abstract]
Accumulated deficit			$ (233,338)	$ (217,502)
Basis of Presentation [Abstract]
Gain on dissolution of foreign subsidiary			$ 1,202
Accounts Receivable [Abstract]
Accounts receivables maximum credit period from invoice date			30 days
Allowance for doubtful accounts			$ 0	0
Inventories [Abstract]
Finished Goods			1,343	750
Work in Process			342	79
Raw Materials			1,272	968
Total			$ 2,957	$ 1,797
Subsequent Event [Member]
Going Concern [Abstract]
Net proceeds from issuance of public offering					$ 57,700
Minimum [Member]
Nature of Business [Abstract]
Reverse stock split ratio		0.2
Maximum [Member]
Nature of Business [Abstract]
Reverse stock split ratio		0.033
Accounts Receivable [Member]
Revenue, Performance Obligation [Abstract]
Number of major customers \| Customer			0	2
Accounts Receivable [Member] \| Customer One [Member]
Revenue, Performance Obligation [Abstract]
Concentration risk percentage				13.00%
Accounts Receivable [Member] \| Customer Two [Member]
Revenue, Performance Obligation [Abstract]
Concentration risk percentage				12.00%

Nature of Business and Significant Accounting Policies, Property, Plant and Equipment and Revenue Recognition (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 376	$ 239
Impairment losses recognized	$ 0	$ 0
Production Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Production Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	7 years
Office Furniture & Fixtures [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Office Furniture & Fixtures [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	5 years
Computer Software and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Computer Software and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	4 years
Loaners and Demo Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	1 year
Loaners and Demo Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	5 years
Leasehold Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Leasehold Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	5 years
ASC 606 [Member] \| Customer One [Member] \| Net Sales [Member]
Revenue, Performance Obligation [Abstract]
Concentration risk percentage	10.50%	10.00%

Nature of Business and Significant Accounting Policies, Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)	1,663,061	263,290
Reconciliation of reported net loss with reported net loss per share [Abstract]
Net loss	$ (15,836)	$ (18,114)
Deemed dividend to preferred shareholders (see Note 5)	(1,757)	(4,509)
Net loss after deemed dividend	$ (17,593)	$ (22,623)
Weighted average shares outstanding (in shares)	1,649,000	81,000
Basic and diluted loss per share (in dollars per share)	$ (10.67)	$ (278.90)
March 2020 Offering [Member]
Loss per share [Abstract]
Net deemed dividends resulting from subsequent reduction in exercise price of warrants	$ 200
Stock Options [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)	16,889	13,471
Warrants to Purchase Common Stock [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)	1,631,948	231,629
Series F Convertible Preferred Stock [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)	14,224	18,190

Revenue Recognition (Details)	12 Months Ended
Revenue Recognition (Details)	Dec. 31, 2020	Dec. 31, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Abstract]
Expected timing of satisfaction, period		1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Abstract]
Expected timing of satisfaction, period	1 year
Sales Revenue [Member] \| ASC 606 [Member] \| Maximum [Member]
Revenue, Performance Obligation [Abstract]
Percentage of net sales	1.00%	1.00%

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	$ 3,571	$ 3,008
Accumulated Depreciation	(2,371)	(2,017)
Property, Plant and Equipment, Net	1,200	991
Production Equipment [Member]
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	1,201	1,113
Loaners and Demo Equipment [Member]
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	1,073	801
Computer Software and Equipment [Member]
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	691	579
Office Furniture & Fixtures [Member]
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	364	291
Leasehold Improvements [Member]
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	$ 242	$ 224

Debt (Details) - Silicon Valley Bank [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Aug. 05, 2016
Line of Credit Facility [Abstract]
Maximum borrowing capacity	$ 5.0
Term Loan [Member]
Line of Credit Facility [Abstract]
Maximum borrowing capacity			$ 4.0
Maturity date	Nov. 30, 2016
Revolving Line [Member]
Line of Credit Facility [Abstract]
Maximum borrowing capacity	$ 1.0
Maturity date	Mar. 31, 2020
Total borrowings outstanding		$ 0.0
Revolving Line [Member] \| Floating Annual Rate [Member]
Line of Credit Facility [Abstract]
Interest rate	1.75%
Revolving Line [Member] \| Prime Rate [Member]
Line of Credit Facility [Abstract]
Interest rate	1.00%

Stockholders' Equity (Details) $ / shares in Units, $ in Thousands										12 Months Ended
	Aug. 21, 2020 USD ($) $ / shares shares	May 05, 2020 USD ($) $ / shares shares	Apr. 01, 2020 USD ($) shares	Mar. 23, 2020 USD ($) $ / shares shares	Jan. 28, 2020 USD ($) $ / shares shares	Nov. 06, 2019 USD ($) $ / shares shares	Oct. 25, 2019 USD ($) $ / shares shares	Mar. 12, 2019 USD ($) $ / shares shares	Nov. 27, 2017 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) shares	Apr. 02, 2020 $ / shares shares	May 30, 2019 $ / shares shares	Jul. 03, 2018 $ / shares
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)					585,460	40,638	19,196
Warrants exercised to purchase common stock (in shares)										455,162
Proceeds from warrant exercises \| $										$ 4,115	$ 0
Exercise price of warrants (in dollars per share) \| $ / shares				$ 11.18	$ 16.50	$ 29.83	$ 42.30
Preferred stock, shares outstanding (in shares)										0	0
Issuance of common stock, net (in shares)					201,546	40,637	19,195
Public offering price (in dollars per share) \| $ / shares						$ 33.60	$ 34.50
Gross proceeds from public stock offering \| $					$ 9,700	$ 1,360	$ 660
Net proceeds from public stock offering \| $					8,600
Down-round protection in connection with re-pricing of warrants \| $					200
Beneficial conversion amount \| $					$ 1,600
Warrant expiry period				5 years 6 months		5 years	5 years
Warrants exercisable period				6 months			6 months
Expected Stock Price Volatility [Member]
Class of Stock Disclosures [Abstract]
Warrants measurement input										1.3621
March 2019 Offering [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)								15,173
Public offering price (in dollars per share) \| $ / shares								$ 157.50
March 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)				138,715
Exercise price of warrants (in dollars per share) \| $ / shares				$ 9.00
Issuance of common stock, net (in shares)				138,715
Public offering price (in dollars per share) \| $ / shares				$ 9.00
Gross proceeds from public stock offering \| $				$ 1,200
Net proceeds from public stock offering \| $				$ 1,000
April 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)												85,506
Exercise price of warrants (in dollars per share) \| $ / shares												$ 11.15
Issuance of common stock, net (in shares)			171,008
Public offering price (in dollars per share) \| $ / shares												$ 13.02
Gross proceeds from public stock offering \| $			$ 2,200
Warrant expiry period			5 years 6 months
May 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)		59,966
Exercise price of warrants (in dollars per share) \| $ / shares		$ 12.30
Issuance of common stock, net (in shares)		119,930
Public offering price (in dollars per share) \| $ / shares		$ 14.18
Gross proceeds from public stock offering \| $		$ 1,700
Warrant expiry period		5 years 6 months
August 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)	1,064,678
Public offering price (in dollars per share) \| $ / shares	$ 13.50
Gross proceeds from public stock offering \| $	$ 14,400
Net proceeds from public stock offering \| $	$ 13,000
Number of shares issuable on the exercise of warrants (in shares)	1,064,678
Warrant expiry period										5 years
Warrants to Purchase Common Stock [Member]
Class of Stock Disclosures [Abstract]
Number of warrants vested (in shares)										0
Warrants to Purchase Common Stock [Member] \| Minimum [Member]
Class of Stock Disclosures [Abstract]
Exercise price of warrants (in dollars per share) \| $ / shares										$ 9.00
Warrants to Purchase Common Stock [Member] \| Consultant [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)													3,334
Exercise price of warrants (in dollars per share) \| $ / shares										$ 57.90			$ 95.40
Series F Convertible Preferred Stock [Member]
Class of Stock Disclosures [Abstract]
Gross proceeds from issuance of convertible preferred stock \| $									$ 18,000
Net proceeds from issuance of convertible preferred stock \| $									$ 16,200
Conversion price (in dollars per share) \| $ / shares				$ 9.00	$ 16.50	$ 29.83	$ 42.30	$ 157.50	$ 1,890.00					$ 890.40
Number of consecutive trading days considered for expiration										20 days
Number of consecutive trading days										30 days
Preferred stock issued (in shares)									18,000	127	535
Number of shares issuable on conversion of preferred stock (in shares)									9,557
Preferred stock, shares outstanding (in shares)										127	535
Aggregate cash placement fee								8.00%
Series F Convertible Preferred Stock [Member] \| Minimum [Member]
Class of Stock Disclosures [Abstract]
Percentage of volume weighted average price of common stock									300.00%
Trading volume for each trading day \| $									$ 200
Series F Convertible Preferred Stock [Member] \| Warrants to Purchase Common Stock [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)									19,122
Series F Convertible Preferred Stock [Member] \| Warrant Series 1 [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)									16
Exercise price of warrants (in dollars per share) \| $ / shares									$ 1,890.00
Series F Convertible Preferred Stock [Member] \| Warrant Series 2 [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)									16
Exercise price of warrants (in dollars per share) \| $ / shares									$ 1,890.00
Series G Convertible Preferred Stock [Member]
Class of Stock Disclosures [Abstract]
Gross proceeds from issuance of convertible preferred stock \| $								$ 12,400
Net proceeds from issuance of convertible preferred stock \| $								$ 11,000
Conversion price (in dollars per share) \| $ / shares								$ 157.50
Number of consecutive trading days										30 days
Preferred stock, shares outstanding (in shares)											0
Beneficial conversion amount \| $										$ 4,500
Beneficial ownership limitation								4.99%
Conversion of preferred stock into common stock (in shares)											63,685
Series G Convertible Preferred Stock [Member] \| March 2019 Offering [Member]
Class of Stock Disclosures [Abstract]
Number of shares issuable on conversion of preferred stock (in shares)								1,910,536
Series G Convertible Preferred Stock [Member] \| Warrant Series 1 [Member]
Class of Stock Disclosures [Abstract]
Exercise price of warrants (in dollars per share) \| $ / shares								$ 157.50
Number of shares issuable on the exercise of warrants (in shares)								78,863
Series G Convertible Preferred Stock [Member] \| Warrant Series 2 [Member]
Class of Stock Disclosures [Abstract]
Exercise price of warrants (in dollars per share) \| $ / shares								$ 157.50
Number of shares issuable on the exercise of warrants (in shares)								78,863
Series H Preferred Stock [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares					$ 16.50
Preferred stock, shares outstanding (in shares)										0
Issuance of common stock, net (in shares)					11,517,269
Public offering price (in dollars per share) \| $ / shares					$ 16.50
Maximum percentage of the applicable Unit offering price, by which exercise price can be lower than adjustment					10.00%
Conversion of preferred stock into common stock (in shares)										11,517,269

Stock-Based Compensation, Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Stock-Based Compensation Expense Items [Abstract]
Stock-based compensation expense	$ 1,349	$ 1,512
Minimum [Member]
Additional Disclosures [Abstract]
Award vesting period	1 year
Maximum [Member]
Additional Disclosures [Abstract]
Award vesting period	4 years
Selling, General and Administrative [Member]
Stock-Based Compensation Expense Items [Abstract]
Stock-based compensation expense	$ 1,252	1,387
Research and Development [Member]
Stock-Based Compensation Expense Items [Abstract]
Stock-based compensation expense	$ 97	$ 125
Stock Options [Member]
Stock Options Activity [Roll Forward]
Outstanding, beginning balance (in shares)	13,471	4,638
Granted (in shares)	5,542	9,374
Exercised (in shares)	0	0
Forfeited/expired (in shares)	(2,124)	(541)
Outstanding, ending balance (in shares)	16,889	13,471
Vested at the end of the year (in shares)	7,254	2,383
Weighted Average Exercise Price [Abstract]
Outstanding, beginning balance (in dollars per share)	$ 515.33	$ 1,461.24
Granted (in dollars per share)	10.03	71.40
Exercised (in dollars per share)	0	0
Forfeited/expired (in dollars per share)	71.51	926.31
Outstanding, ending balance (in dollars per share)	405.34	515.33
Vested at the end of the year (in dollars per share)	$ 697.37	$ 1,417.42
Weighted Average Remaining Contractual Term [Abstract]
Options outstanding, weighted average remaining contractual life	8 years 5 months 19 days
Options vested, weighted average remaining contractual life	8 years 25 days
Aggregate Intrinsic Value [Abstract]
Fair value of options, vested	$ 1,700	$ 2,400
Weighted Average Assumptions used in Black-Scholes Option Pricing Model [Abstract]
Expected dividend yield	0.00%	0.00%
Risk-free interest rate	0.65%	1.85%
Expected volatility	127.87%	121.67%
Expected life	5 years 10 months 28 days	6 years 2 months 19 days
Additional Disclosures [Abstract]
Weighted-average fair value of options granted (in dollars per share)	$ 8.79	$ 62.37
Total unrecognized compensation costs related to non-vested stock option awards	$ 1,500
Unrecognized compensation costs related to non-vested stock option awards, recognition period	2 years 6 months 11 days

Stock-Based Compensation, Warrants (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Mar. 23, 2020	Jan. 28, 2020	Dec. 31, 2019	Nov. 06, 2019	Oct. 25, 2019
Class of Warrant or Right [Abstract]
Exercise price of warrants (in dollars per share)		$ 11.18	$ 16.50		$ 29.83	$ 42.30
Warrants [Member]
Class of Warrant or Right [Abstract]
Warrants outstanding (in shares)	1,631,948			231,629
Warrants [Member] \| Minimum [Member]
Class of Warrant or Right [Abstract]
Exercise price of warrants (in dollars per share)	$ 9.00
Warrants exercisable period	10 months
Warrants [Member] \| Maximum [Member]
Class of Warrant or Right [Abstract]
Exercise price of warrants (in dollars per share)	$ 53,550
Warrants exercisable period	4 years 10 months 24 days

Fair Value of Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Fair Value Transfers between levels [Abstract]
Level 1 to Level 2 asset transfers	$ 0	$ 0
Level 2 to Level 1 asset transfers	0	0
Level 1 to Level 2 liability transfers	0	0
Level 2 to Level 1 liability transfers	$ 0	$ 0

Income Taxes, Domestic and Foreign Loss Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Loss before income taxes [Abstract]
Domestic	$ (15,865)	$ (18,114)
Foreign	38	8
Loss before income taxes	$ (15,827)	$ (18,106)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8906-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(8))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 235
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-URI http://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8924-108599

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

+ Details

Income Taxes, Components of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Current [Abstract]
United States and state	$ 0	$ 0
Foreign, net	(9)	(8)
Deferred [Abstract]
United States and state	0	0
Foreign	0	0
Total income tax expense	$ (9)	$ (8)

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Income Taxes, Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Effective income tax rate reconciliation [Abstract]
Statutory federal income tax benefit	$ 3,324	$ 3,802
State tax benefit, net of federal taxes	94	46
Foreign tax	(1)	1
Foreign deferred exchange rate adjustments	1,027	(59)
Dissolution of foreign subsidiary	(11,401)	0
Nondeductible/nontaxable items	34	(272)
Other	(255)	(113)
Valuation allowance (increase) decrease	7,169	(3,413)
Total income tax expense	$ (9)	$ (8)

Income Taxes, Deferred Taxes and Other Information (Details) $ in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2020 AUD ($)
Noncurrent [Abstract]
Accrued leave	$ 61	$ 51
Other accrued expenses	0	0
Stock based compensation	293	449
Net operating loss carryforward	37,665	44,572
Other	11	69
Intangibles	751	809
R&D credit carryforward	531	531
Total deferred tax assets	39,312	46,481
Less: valuation allowance	(39,312)	(46,481)
Total	0	0
Operating Loss Carryforwards [Abstract]
Increase (decrease) in valuation allowance	(7,200)	3,400
Unrecognized Tax Benefits [Abstract]
Uncertain tax positions	0	0
Penalties and Interest Accrued [Abstract]
Interest and penalties accrued on uncertain tax positions	$ 0	$ 0
Earliest Tax Year [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss (NOL) carryforwards, expiration date	Dec. 31, 2024
Latest Tax Year [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss (NOL) carryforwards, expiration date	Dec. 31, 2037
Federal [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss (NOL) carryforwards	$ 168,200
Net operating loss (NOL) carryforwards with expiration date	120,100
Net operating loss (NOL) carryforwards with no expiration date	48,100
State [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss (NOL) carryforwards	$ 30,900
Australian [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss (NOL) carryforwards			$ 0

Operating Leases (Details) $ in Thousands	12 Months Ended
Operating Leases (Details) $ in Thousands	Dec. 31, 2020 USD ($) $ / ft²	Dec. 31, 2019 USD ($)
Operating Leases [Abstract]
Annual base rent (per square foot) \| $ / ft²	9.00
Annual increase per square foot (in dollars per square foot) \| $ / ft²	0.25
Cost Components of Operating Leases [Abstract]
Operating lease cost	$ 213	$ 213
Variable lease cost	114	102
Total	327	$ 315
Maturities of Lease Liability [Abstract]
2021	219
2022	55
Total lease payments	274
Less: Interest	(13)
Present value of lease liability	$ 261
Remaining lease term	1 year 3 months	2 years 3 months
Discount rate	7.50%	7.50%
Operating cash outflows from operating lease	$ 213	$ 206

Finance Lease Liability (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Finance Lease Liability (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Finance Lease Liability [Abstract]
Value of finance lease equipment	$ 98	$ 98	$ 0
Principal amount under lease agreement	$ 93	$ 93
Implied interest rate	7.50%	7.50%
Finance lease term	39 months	39 months

Commitments and Contingencies - (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Aug. 31, 2016
Employee Retirement Plan [Abstract]
Employer's matching contribution	$ 234	$ 227
Aquadex Product Line [Member]
Contingent Consideration [Abstract]
Fair value of contingent consideration			$ 126
Contingent consideration		$ 0

Related Party Transactions (Details) - USD ($)	12 Months Ended
Related Party Transactions (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Abstract]
Service charges from related party	$ 0
Steven Brandt [Member]
Related Party Transaction [Abstract]
Monthly fee with related party		$ 19,000
Service charges from related party		76,000
Reimbursement expenses with related party		$ 2,453

Segment and Geographic Information (Details)	12 Months Ended
Segment and Geographic Information (Details)	Dec. 31, 2020 Segment
Segment and Geographic Information [Abstract]
Number of reportable segments	1

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 19, 2021	Mar. 23, 2020	Jan. 28, 2020	Nov. 06, 2019	Oct. 25, 2019	Mar. 12, 2019	Jul. 03, 2018	Nov. 27, 2017
Subsequent Events [Abstract]
Issuance of common stock, net (in shares)			201,546	40,637	19,195
Gross proceeds from public stock offering			$ 9,700	$ 1,360	$ 660
Net proceeds from public stock offering			$ 8,600
Exercise price of warrants (in dollars per share)		$ 11.18	$ 16.50	$ 29.83	$ 42.30
Subsequent Event [Member]
Subsequent Events [Abstract]
Issuance of common stock, net (in shares)	3,795,816
Gross proceeds from public stock offering	$ 20,900
Net proceeds from public stock offering	$ 19,000
March 2020 Offering [Member]
Subsequent Events [Abstract]
Issuance of common stock, net (in shares)		138,715
Gross proceeds from public stock offering		$ 1,200
Net proceeds from public stock offering		$ 1,000
Exercise price of warrants (in dollars per share)		$ 9.00
March 2021 Offering [Member] \| Subsequent Event [Member]
Subsequent Events [Abstract]
Exercise price of warrants (in dollars per share)	$ 5.50
Series F Convertible Preferred Stock [Member]
Subsequent Events [Abstract]
Conversion price (in dollars per share)		$ 9.00	$ 16.50	$ 29.83	$ 42.30	$ 157.50	$ 890.40	$ 1,890.00
Series F Convertible Preferred Stock [Member] \| Subsequent Event [Member]
Subsequent Events [Abstract]
Conversion price (in dollars per share)	$ 5.50