8-K

UNITED STATESSECURITIES AND EXCHANGE COMMISSIONWASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

SeaStar Medical Holding Corporation

(Exact name of Registrant as Specified in Its Charter)

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 5.07 Submission of Matters to a Vote of Security Holders.

The special meeting of stockholders, as adjourned (the “Special Meeting”) of SeaStar Medical Holding Corporation (the “Company”) was held virtually on March 28, 2025, at 10:00 a.m., Mountain Time. The following proposals were approved by the stockholders, each by the votes set forth below:

Proposal 1. To approve, for purposes of complying with Nasdaq Listing Rule 5635(d), the issuance of Common Warrants and Common Warrant Shares upon the exercise thereof:

Proposal 2. To approve, for purposes of complying with Nasdaq Listing Rule 5635(d), the extension of the term of the Company's series B Warrants:

Proposal 3. To approve a proposal to adjourn or postpone the Special Meeting to a later date or dates, if necessary, to permit further solicitation and vote of proxies if there are insufficient votes for, or otherwise in connection with, the approval of the foregoing proposals:

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.