Note 12 - Preferred Stock (Details Textual) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
	Jan. 09, 2023	Mar. 31, 2025	Dec. 31, 2024
Series X Preferred Stock [Member]
Convertible Preferred Stock, Shares Issued upon Conversion (in shares)	100
Preferred Stock, Convertible, Conversion Price (in dollars per share)	$ 32
Preferred Stock, Shares Outstanding (in shares)		12,656	12,656
Series A Convertible Preferred Stock [Member]
Convertible Preferred Stock, Shares Issued upon Conversion (in shares)		62.5
Preferred Stock, Shares Outstanding (in shares)		0
Conversion of Stock, Maximum Threshold Percentage Allowing Conversion		9.99%
Old Catheter [Member] | Series X Preferred Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)	14,649.592
Old Catheter [Member] | Conversion of Convertible Promissory Notes into Series X Preferred Stock [Member]
Debt Conversion, Original Debt, Amount	$ 25.2