Lucid Diagnostics Inc美股招股说明书(2026-04-23版)

Lucid Diagnostics Inc. Common Stock We are offering 18,000,000 shares of our common stock pursuant to this prospectus supplement and the accompanying baseprospectus. Our common stock is listed for trading on the Capital Market of the Nasdaq Stock Market, or “Nasdaq,” under the symbol “LUCD.”On April 22, 2026, the last reported sales price of our common stock was $1.31 per share. (1)We have also agreed to reimburse the underwriters for certain out-of-pocket accountable expenses incurred by them inconnection with this offering, up to a maximum of $75,000. See “Underwriting” for additional information. Investing in our common stock involves a high degree of risk. See the section entitled “Risk Factors” beginning on page S-6 ofthis prospectus supplement and in the documents incorporated by reference herein and in the accompanying base prospectusfor a discussion of information that should be considered in connection with an investment in our common stock. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of thesesecurities or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying base prospectus. Anyrepresentation to the contrary is a criminal offense. Delivery of the shares is expected to be made against payment therefore on or about April 24, 2026. Joint Bookrunners Canaccord Genuity BTIG The date of this prospectus supplement is April 23, 2026. TABLE OF CONTENTS ABOUT THIS PROSPECTUS SUPPLEMENTS-iiMARKET AND INDUSTRY DATAS-iiTRADEMARKSS-iiiNOTE ON FORWARD-LOOKING STATEMENTS AND RISK FACTOR SUMMARYS-iiiGLOSSARYS-ivPROSPECTUS SUPPLEMENT SUMMARYS-1THE OFFERINGS-5RISK FACTORSS-6USE OF PROCEEDSS-10CAPITALIZATIONS-11DILUTIONS-12DESCRIPTION OF COMMON STOCKS-13UNDERWRITINGS-14LEGAL MATTERSS-16EXPERTSS-16WHERE YOU CAN FIND MORE INFORMATIONS-16INFORMATION INCORPORATED BY REFERENCES-17 PROSPECTUS ABOUT THIS PROSPECTUSiiMARKET AND INDUSTRY DATAiiTRADEMARKSiiiNOTE ON FORWARD-LOOKING STATEMENTS AND RISK FACTOR SUMMARYiiiGLOSSARYivPROSPECTUS SUMMARY1RISK FACTORS5USE OF PROCEEDS5DESCRIPTION OF CAPITAL STOCK6DESCRIPTION OF DEBT SECURITIES11DESCRIPTION OF WARRANTS17DESCRIPTION OF THE UNITS18PLAN OF DISTRIBUTION OF SECURITIES19LEGAL MATTERS22EXPERTS22WHERE YOU CAN FIND MORE INFORMATION22INFORMATION INCORPORATED BY REFERENCE23 ABOUT THIS PROSPECTUS SUPPLEMENT This prospectus supplement and the accompanying base prospectus are part of a registration statement under the Securities Act onForm S-3 that we filed with the Securities and Exchange Commission, or the “SEC,” using a “shelf” registration process. Under thisshelf process, we may, from time to time, sell or issue any of the combination of securities described in the accompanying baseprospectus in one or more offerings with a maximum aggregate offering price of up to $175,000,000. The base prospectus provides you with a general description of the securities we may offer under the registration statement. Thisprospectus supplement provides specific details regarding this offering of 18,000,000 shares of our common stock. Generally, whenwe refer only to the “prospectus,” we are referring to both parts combined. This prospectus supplement contains specific informationabout the terms of this offering. This prospectus supplement may also add, update or change information contained in theaccompanying base prospectus. If there is any inconsistency between the information in this prospectus supplement and theaccompanying base prospectus, you should rely on the information in this prospectus supplement. You should read both thisprospectus supplement and the accompanying base prospectus, together with the additional information described below under theheading “Where You Can Find More Information” and “Information Incorporated by Reference.” You should rely only on the information contained or incorporated by reference in this prospectus supplement and the accompanyingbase prospectus and in any issuer free writing prospectus relating to this offering. We have not authorized anyone to provide you withdifferent information and, if provided, such information or representations must not be relied upon as having been authorized by us.Neither this prospectus supplement nor the accompanying base prospectus nor any issuer free writing prospectus shall constitute anoffer to sell or a solicitation of an offer to buy offered securities in any jurisdiction in which it is unlawful for such person to makesuch an offering or solicitation. This prospectus supplement and the accompanying base prospectus and any issuer free writingprospectus do not contain all of the information included in the registration statement. For a more complete understanding of theoffering of the securities, you should refer to the registration statement, including its exhibits. You should not assume that the information appearing in this prospectus supplement or the information appearing in the accompanyingbase pros