Note 1 - Organization and Nature of Operations (Details Textual) $ / shares in Units, $ in Thousands				3 Months Ended						9 Months Ended
	Aug. 15, 2025 $ / shares	May 22, 2025	May 12, 2025 USD ($) $ / shares shares	Sep. 30, 2025 USD ($) $ / shares shares	Jun. 30, 2025 USD ($)	Mar. 31, 2025 USD ($)	Sep. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2025 USD ($) $ / shares shares	Sep. 30, 2024 USD ($)	Oct. 17, 2025 shares	Jun. 20, 2025	Feb. 28, 2025	Dec. 31, 2024 USD ($) $ / shares shares
Stock, Shares Authorized (in shares) | shares				70,000,000						70,000,000
Common Stock, Shares Authorized (in shares) | shares				60,000,000						60,000,000					60,000,000
Preferred Stock, Shares Authorized (in shares) | shares				10,000,000						10,000,000					10,000,000
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares	$ 0.0001			$ 0.0001						$ 0.0001					$ 0.0001
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest | $				$ (2,344)	$ (5,458)	$ (4,045)	$ (4,120)	$ (4,220)	$ (2,675)	$ (11,847)	$ (11,015)
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation | $										(6,784)	$ (6,407)
Retained Earnings (Accumulated Deficit) | $				(303,757)						(303,757)					$ (292,352)
Working Capital (Deficit) | $				(2,900)						(2,900)
Cash and Cash Equivalent | $				$ 1,075						$ 1,075					$ 2,873
Preferred Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares				$ 0.0001						$ 0.0001					$ 0.0001
Series L Warrants [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares				$ 9.5						$ 9.5
Series B Preferred Stock [Member]
Preferred Stock, Shares Authorized (in shares) | shares				3,000						3,000					3,000
Preferred Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares				$ 0.0001						$ 0.0001					$ 0.0001
May 2025 PIPE Financing [Member]
Proceeds from Issuance or Sale of Equity | $			$ 1,500
Offering Fees | $			400
Stock Issued During Period, Value, New Issues | $					$ 2,034
Payments of Stock Issuance Costs | $			$ 400
May 2025 PIPE Financing [Member] | Series L Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) | shares			150
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares			$ 9.5
May 2025 PIPE Financing [Member] | PIPE Units [Member]
Stock Issued During Period, Shares, New Issues (in shares) | shares			1,500
Units Issued, Series B Preferred Shares Per Unit			1
May 2025 PIPE Financing [Member] | Series B Preferred Stock [Member]
Stock Issued During Period, Shares, New Issues (in shares) | shares			1,500
Preferred Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares			$ 0.0001
ATM Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares) | shares										868,582
Stock Issued During Period, Value, New Issues | $										$ 4,000
Payments of Stock Issuance Costs | $										$ 300
Cardionomic's Late-stage Treatment for Acute Decompensated Heart Failure [Member]
Debt Instrument, Term (Year)		3 years
Reverse Stock Split [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	19									19
Subsequent Event [Member]
Stock, Shares Authorized (in shares) | shares												510,000,000
Common Stock, Shares Authorized (in shares) | shares												500,000,000
Preferred Stock, Shares Authorized (in shares) | shares												10,000,000
Cardionomix Inc. [Member]
Subsidiary, Ownership Percentage, Parent				82.00%						82.00%				82.00%
Cardionomix Inc. [Member] | Chief Executive Officer and Chairman of the Board [Member]
Subsidiary, Ownership Percentage, Parent				12.00%						12.00%
Cardionomix Inc. [Member] | Certain Third Parties [Member]
Subsidiary, Ownership Percentage, Parent				6.00%						6.00%
KardioNav, Inc. [Member]
Subsidiary, Ownership Percentage, Parent				57.00%						57.00%			57.00%
KardioNav, Inc. [Member] | Chief Executive Officer and Chairman of the Board [Member]
Subsidiary, Ownership Percentage, Parent				10.00%						10.00%
KardioNav, Inc. [Member] | Certain Third Parties [Member]
Subsidiary, Ownership Percentage, Parent				33.00%						33.00%
KardioNav, Inc. [Member] | Chelak iECG, Inc. [Member]
Subsidiary, Ownership Percentage, Parent				33.00%						33.00%