<PAGE>

                         CONFIDENTIAL TREATMENT REQUESTED

    The Company has requested confidential treatment of certain portions
    of this exhibit on pages 1, 2, 3 and 4 of the Amendment between
    St. Jude Medical, Inc. and Heartport, Inc. dated as of January 31, 1997.

    *Confidential portion has been omitted and filed separately with the 
     Commission.


                                    AMENDMENT


This Amendment (the "Amendment") is made effective the 31st day of January, 1997
(the "Amendment Date") by and between St. Jude Medical, Inc. ("SJM"), a
Minnesota corporation, whose principal offices are located at One Lillehei
Plaza, St. Paul, Minnesota 55117 and Heartport, Inc., a Delaware corporation,
whose principal offices are located at 200 Chesapeake Drive, Redwood City,
California 94063 ("Heartport").  This Amendment is the first amendment to that
certain Agreement by and between SJM and Heartport dated as of September 11,
1995 (the "Agreement").  All terms of such Agreement not modified hereby shall
remain in full force and effect.  As set forth in Section 14.9 of the Agreement,
the Agreement as amended by this Amendment, together with the documents
mentioned in Section 14.9, shall constitute the entire agreement of the parties
relating to its subject matter.  All capitalized terms not defined herein shall
have the meanings given them in the Agreement.

The parties, intending to be legally bound, agree to the following amendments to
the Agreement:

With respect to Section 2.1 regarding the Note dated September 11, 1995 
executed by Heartport in favor of SJM and attached as Exhibit A to the 
Agreement (the "Note"), the parties agree that all conditions under the 
heading Reduction of Note were met on September 30, 1996 and the Note's 
balance of [*] shall be deemed to be non-interest bearing, nonrefundable, 
prepaid royalties of SJM to Heartport in accordance with the terms of the 
Note, the Agreement and this Amendment.

With respect to Section 2.2, the parties agree that SJM shall not be obligated
to pay Heartport [*] as non-interest bearing, nonrefundable, prepaid
royalties.

Section 5.1 is deleted in its entirety and replaced with the following:

     5. 1      MINIMUM ROYALTY.  Notwithstanding any other sections of this
               Agreement, in the event the royalty payment calculated under
               Section 5.2 is less than the minimum royalty set forth in this
               Section 5.1, SJM will pay Heartport a minimum royalty of [*] per
               each CCVDS Transferred (defined below) to a third party worldwide
               unless Heartport agrees in writing to a different minimum royalty
               level.  For each CCVDS Transferred to any third party worldwide,
               [*].

Section 5.2 is deleted in its entirety and replaced with the following:


                                        1


<PAGE>

                         CONFIDENTIAL TREATMENT REQUESTED

    *Confidential portion has been omitted and filed separately with the 
     Commission.


     5. 2      ROYALTY FORMULA.  For each CCVDS Transferred to any third party
               worldwide, SJM shall pay Heartport a royalty equal to the greater
               of (i) [*] of [*] of each CCVDS sold in the country of 
               such third party and the [*] of the counterpart SJM Prosthesis 
               designed and intended for use in conventional open heart valve 
               replacement and repair procedures (a "Counterpart Conventional 
               Prosthesis") in that same country or (ii) where SJM does not 
               offer for sale a Counterpart Conventional Prosthesis in the 
               country of such third party, [*] of [*] of each CCVDS sold
               in the country of such third party and the [*] of a Counterpart 
               Conventional Prosthesis last sold in that country adjusted by 
               the [*] of other SJM products in that country or, if no such 
               SJM products are sold in such country, the [*] of other SJM
               products in a country with similar pricing.  The total royalty
               payment obligation for each CCVDS type (e.g., SJM-Registered
               Trademark- Mechanical Heart Valve, SJM-Registered Trademark-
               Master Series, SJM-Registered Trademark- Hemodynamic Plus Series,
               SJM-Registered Trademark- Annuloplasty Ring, etc.) in each
               country shall be calculated as follows:

               [*]

               Total royalty payments in each quarter will be calculated by
               summing royalty payment obligations for all CCVDS types in all
               countries in which CCVDSs are Transferred.  [*] shall be 
               recalculated each calendar quarter.  Example: The [*] of a 
               CCVDS incorporating an SJM-Registered Trademark- Masters 
               Series Mechanical Heart Valve in France during the third 
               calendar quarter of 1997 is [*].  The [*] of the counterpart 
               SJM-Registered Trademark- Masters Series Mechanical Heart 
               Valve intended for use in conventional open procedures in 
               France during that same quarter is [*].  The royalty payment 
               obligation for each CCVDS incorporating an SJM-Registered 
               Trademark- Masters Series Mechanical Heart Valve in France 
               during the third calendar quarter of 1997 is [*].

Section 5.3 is deleted in its entirety and is reserved.

Section 5.4 is deleted in its entirety and replaced with the following:

     5. 4      The parties, after considering a number of alternatives, have 
               agreed that, for mutual convenience, and in lieu of negotiating 
               milestone payments, technology transfer fees and the like, that 
               subject to the suspension provision of Section 5.9, [*], as a 
               technology fee for sales [*], provided that if the sale were to 
               occur in the United States, a patent royalty would be owed and 
               that the duty to pay the technology fee (as opposed to the [*] in
               each country [*] a) when a Licensed Patent issues covering such 
               sales in the country or b) when a [*] (i.e. a closed-chest 
               valve delivery system consisting of a prosthesis and a prosthesis
               holder, each of which is manufactured and intended for use in a 
               closed-chest valve delivery system), manufactured and marketed 
               by [*] bound by agreement with Heartport to pay a comparable fee 
               meeting the standards of Section 5.10, becomes available in 
               that country.


                                        2


<PAGE>

                         CONFIDENTIAL TREATMENT REQUESTED

    *Confidential portion has been omitted and filed separately with the 
     Commission.


Section 5.10 is deleted in its entirety and replaced with the following:

     5.10      MOST FAVORED LICENSEE STATUS.  (i) PRODUCTS NOT INCORPORATING A
               [*].  Heartport will not grant to any other licensee receiving 
               a license to make, use or sell Less Invasive Prosthesis Holders 
               or closed-chest valve delivery systems (which shall be defined 
               as a CCVDS which includes a non-SJM Prosthesis that incorporates 
               a valve product other than a [*] instead of an SJM Prosthesis) 
               in the field of closed-chest valve repair or replacement a 
               license [*] than those extended to SJM in this Agreement or 
               under [*] less restrictive than those extended to SJM, unless 
               those terms are similarly extended to SJM with respect to [*] 
               granted to such other licensee.  In the event Heartport grants 
               a license covered by this Section 5.10, Heartport shall provide 
               SJM written notice of such License within thirty (30) days of 
               grant.  Such notice should include a certification that such 
               other agreement does not require Heartport to grant a [*]  
               to SJM under this Section 5.10.  (ii) PRODUCTS INCORPORATING A
               [*].  Notwithstanding the foregoing, the parties agree that 
               Heartport may, without restriction, grant licenses to make, use 
               or sell Less Invasive Prosthesis Holders or closed-chest valve 
               delivery systems that incorporate a [*].  In the event that 
               Heartport grants such a license with respect to [*] to one
               or more third parties, Heartport agrees that, at such time as SJM
               has completed the design and/or regulatory approval process for a
               [*] to be utilized in a closed-chest valve delivery system in 
               any country, at the request of SJM Heartport must grant SJM 
               a license with respect to [*]

6.   DELIVERY HANDLE.

     All sections, Section 6.1 through Section 6.5 are deleted in their entirety
and are reserved.


                                        3


<PAGE>

                         CONFIDENTIAL TREATMENT REQUESTED

    *Confidential portion has been omitted and filed separately with the 
     Commission.


Section 14.10 is added in its entirety:

     14.10     RENEGOTIATION.  After the [*] anniversary of the Amendment
               Date, SJM shall have the right to request renegotiation of the
               [*] set forth in [*]; provided, however, that any amendment 
               to the Agreement resulting from such negotiations shall be [*]

Section 15.1 is deleted in its entirety and replaced with the following:

     15. 1     CCVDS.  "CCVDS" shall consist of no more than one of each of the
               following:  an SJM Prosthesis and a Less Invasive Prosthesis
               Holder.

Section 15.3 is deleted in its entirety and replaced with the following:

     15. 3     HEARTPORT PORT-ACCESS DELIVERY HANDLE.  "Heartport Port-Access
               Delivery Handle" and the "Handle" shall mean a handle developed
               and manufactured by Heartport or its designee.

Section 15.5 is deleted in its entirety and replaced with the following:

     15. 5     LESS INVASIVE PROSTHESIS HOLDER.  "Less Invasive Prosthesis
               Holder" shall mean prosthesis holders compatible with a Heartport
               Port-Access Delivery Handle or covered by Heartport patents,
               including, but not limited to, prosthesis holders covered by
               Heartport method patents when sale of the prosthesis holder in
               the absence of a license would constitute contributory
               infringement of such patents.

Section 15.14 is added in its entirety:

     15.14     [*] shall mean a [*]. This includes, but is not limited to, [*].

Section 15.15 is added in its entirety:

     15.15     [*] shall mean any [*] whose primary function is to [*].

Section 15.16 is added in its entirety:


                                        4


<PAGE>

                         CONFIDENTIAL TREATMENT REQUESTED


     15.16     TRANSFERRED OR TRANSFER.  "Transferred" or "Transfer" shall mean
               a transaction in which the title of a CCVDS is transferred for
               compensation or as part of an agreement.  Transfer includes, but
               is not limited to, a valve transferred as part of a VIP
               agreement.  Transfer excludes consigned inventory and product
               donated for humanitarian or scientific purposes.


                     [The remainder of this page is blank.]


                                        5


<PAGE>

                         CONFIDENTIAL TREATMENT REQUESTED


IN WITNESS WHEREOF, authorized representatives of the parties have executed this
Amendment to the Agreement as of the Amendment Date.


HEARTPORT, INC.                         ST. JUDE MEDICAL, INC.


/s/ Wesley D. Sterman, M.D.             /s/ Ronald A. Matricaria
-------------------------------------   ----------------------------------------
Wesley D. Sterman, M.D.                 Ronald A. Matricaria
President and Chief Executive Officer   President and Chief Executive Officer


                                        6