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                       SECURITIES AND EXCHANGE COMMISSION
 
                             WASHINGTON, D.C. 20549
 
                            ------------------------
 
                                 FORM 10-K/A-2
                                ---------------
 
                                AMENDMENT NO. 2
                                       TO
 
(Mark One)
 
/X/  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934. FOR THE FISCAL YEAR ENDED DECEMBER 31, 1996
 
                                       OR
 
/ /  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
     EXCHANGE ACT OF 1934
 
            For the transition period from            to
 
                         Commission file number 0-28266
 
                            ------------------------
 
                                HEARTPORT, INC.
 
             (Exact Name of Registrant as Specified in Its Charter)
 
<TABLE>
<S>                               <C>
            DELAWARE                   94-3222307
(State or Other Jurisdiction of     (I.R.S. Employer
 Incorporation or Organization)      Identification
                                         Number)
</TABLE>
 
                  200 CHESAPEAKE DRIVE, REDWOOD CITY, CA 94063
 
               Address of Principal Executive Offices) (Zip Code)
 
                            ------------------------
 
                                 (415) 306-7900
 
               Registrant's Telephone Number, Including Area Code
 
                            ------------------------
 
        Securities registered pursuant to Section 12(b) of the Act: NONE
 
    Securities registered pursuant to Section 12(g) of the Act: COMMON STOCK
 
                                (Title of Class)
 
    Indicate by check mark whether the registrant: (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes _X_ No ____
 
    Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. _X_
 
    The aggregate market value of the voting stock held by non-affiliates of the
registrant as of March 14, 1997: approximately $324 million (based on the last
reported sale price of $27.25 per share on March 14, 1997 on the Nasdaq National
Market).
 
    The number of shares of Common Stock outstanding as of March 14, 1997 was
24,567,738.
 
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                                    PART IV
 
ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K.
 
(a) EXHIBITS
 
<TABLE>
<CAPTION>
EXHIBIT NO.                                               DESCRIPTION
-----------  -----------------------------------------------------------------------------------------------------
<S>          <C>
      2.1+   Agreement and Plan of Merger dated April 3, 1995, for the reincorporation merger of Stanford Surgical
               Technology, Inc., a California corporation, into Heartport, Inc., a Delaware corporation.
 
      3.1+   Restated Certificate of Incorporation.
 
      3.2+   Bylaws of the Registrant.
 
       4.1   Reference is made to Exhibits 3.1 and 3.2.
 
      4.2+   Specimen Common Stock certificate.
 
      4.3+   Third Amended and Restated Rights Agreement among Registrant and the Founders and Investors specified
               therein dated April 17, 1995.
 
      4.4#   Rights Agreement between the Registrant and the First National Bank of Boston dated April 25, 1996.
 
     10.1+   Form of Indemnification Agreement entered into by and between Registrant and its officers and
               directors.
 
     10.2+   1993 Stock Option Plan and forms of agreements thereunder.
 
     10.3#   1996 Stock Option Plan as amended and restated October 21, 1996.
 
     10.4#   Employee Stock Purchase Plan, as amended and restated October 21, 1996.
 
     10.5+   Real Property Lease between the Registrant and Metropolitan Insurance Company dated September 21,
               1992, as amended.
 
     10.6+   Equipment Financing Agreement between the Registrant and Lease Management Services, Inc. dated
               February 23, 1995.
 
    10.7+*   Agreement between the Company and St. Jude Medical, Inc. dated September 11, 1995.
 
     10.8#   Third Amendment to Lease Agreement between Heartport Research and Training Center, Inc. and
               University of Utah Research Foundation dated as of October 25, 1996.
 
     10.9*   Amendment to agreement between Registrant and St. Jude Medical, Inc. dated January 31, 1997.
 
    10.10#   Loan and Security Agreement dated December 31, 1996 between the Registrant and Silicon Valley Bank.
 
     11.1#   Computation of Net Loss Per Share.
 
     23.1#   Consent of Ernst & Young LLP, Independent Auditors.
 
     27.1#   Financial Data Schedule
 
      99.1   Proxy Statement for the Registrant's 1997 Annual Meeting of Stockholders.
</TABLE>
 
------------------------
 
*   Confidential treatment has been requested for certain portions of this
    exhibit. Omitted portions have been filed separately with the Securities and
    Exchange Commission.
 
+   Incorporated by reference to the Registrant's Registration Statement on Form
    S-1 (File No. 333-1906)
 
#  Previously filed.
 
                                      IV-1
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                                   SIGNATURES
 
    Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, as amended, the registrant has duly caused this amendment
to its Annual Report on Form 10-K to be signed on its behalf by the undersigned,
thereunto duly authorized, in Redwood City, California, on this 13th day of May,
1997.
 
                                HEARTPORT, INC.
 
                                By:             /s/ DAVID B. SINGER
                                     -----------------------------------------
                                                  David B. Singer
                                         SENIOR VICE PRESIDENT, FINANCE AND
                                              CHIEF FINANCIAL OFFICER
 
    Pursuant to the requirements of the Securities Exchange Act of 1934, as
amended, this amendment to Annual Report on Form 10-K has been signed below by
the following persons on behalf of the registrant and in the capacities and on
the dates indicated:
 
          SIGNATURE                       TITLE                    DATE
------------------------------  --------------------------  -------------------
 
                                President, Chief Executive
 /s/ WESLEY D. STERMAN, M.D.*     Officer and Director
------------------------------    (Principal Executive         May 13, 1997
   Wesley D. Sterman, M.D.        Officer)
 
                                Senior Vice President,
     /s/ DAVID B. SINGER          Finance and Chief
------------------------------    Financial Officer            May 13, 1997
       David B. Singer            (Principal Financial and
                                  Accounting Officer)
 
    /s/ FRANK M. FISCHER*
------------------------------  Director                       May 13, 1997
       Frank M. Fischer
 
   /s/ ROBERT V. GUNDERSON,
             JR.*
------------------------------  Director                       May 13, 1997
   Robert V. Gunderson, Jr.
 
     /s/ JOSEPH S. LACOB*
------------------------------  Director                       May 13, 1997
       Joseph S. Lacob
 
  /s/ JOHN H. STEVENS, M.D.*
------------------------------  Director                       May 13, 1997
    John H. Stevens, M.D.
 
  /s/ PETRI T. VAINIO, M.D.*
------------------------------  Director                       May 13, 1997
    Petri T. Vainio, M.D.
 
  /s/ STEVEN C. WHEELWRIGHT*
------------------------------  Director                       May 13, 1997
    Steven C. Wheelwright
 
*By:     /s/ DAVID B. SINGER
      -------------------------
           David B. Singer
          Attorney-in-Fact
 
                                      IV-3