<PAGE>


                                                                  EXHIBIT E
                               STOCK OPTION AGREEMENT


     THIS AGREEMENT is dated as of July 12, 1998, between MEDTRONIC, INC., a
Minnesota corporation ("Grantee"), and AVECOR CARDIOVASCULAR, INC., a Minnesota
corporation ("Issuer").

                                      RECITALS

     A.   Grantee, Issuer, and AC Merger Corp., a Minnesota corporation and
wholly-owned subsidiary of Grantee ("Merger Subsidiary"), are entering into an
Agreement and Plan of Merger (the "Merger Agreement") which provides, among
other things, that, upon the terms and subject to the conditions thereof, Merger
Subsidiary will be merged with and into Issuer (the "Merger").

     B.   Prior to the execution and delivery of this Agreement, certain
directors and officers of Issuer have, to induce Grantee to execute the Merger
Agreement, executed and delivered to Grantee the Agreements to Facilitate Merger
described in the Merger Agreement.

     C.   As a further and subsequent inducement to have Grantee enter into the
Merger Agreement, Grantee has required that Issuer enter into this Agreement,
which provides, among other things, that Issuer grant to Grantee an option to
purchase shares of Issuer's Common Stock, par value $.0l per share ("Issuer
Common Stock"), upon the terms and subject to the conditions provided for
herein.

     NOW, THEREFORE, in consideration of the premises and mutual covenants and
agreements contained in this Agreement and the Merger Agreement, the parties
agree as follows:

     1.   GRANT OF OPTION.  Subject to the terms and conditions of this
Agreement, Issuer hereby grants to Grantee an irrevocable option (the "Option")
to purchase 1,600,851 shares of Issuer Common Stock (the "Option Shares"), in
the manner set forth below, at an exercise price of $11.125 per share of Issuer
Common Stock, subject to adjustment as provided below (the "Option Price"). 
Issuer represents that the Option Shares represent at least 19.9% of the number
of shares of Issuer Common Stock outstanding on the date hereof.  Capitalized
terms used herein but not defined herein shall have the meanings set forth in
the Merger Agreement.


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<PAGE>


     2.   EXERCISE OF OPTION.

          (a)  Subject to the satisfaction or waiver of the conditions set forth
     in Section 9 of this Agreement, prior to the termination or expiration of
     this Agreement in accordance with its terms, Grantee or its designee (which
     shall be a wholly-owned subsidiary of Grantee) may exercise the option, in
     whole or in part, at any time or from time to time on or after the public
     disclosure of, or the time at which Grantee shall have learned of, the
     earliest of (i) or (ii) below to occur:

               (i)  the Merger Agreement is terminated pursuant to Section
          7.1(e) of the Merger Agreement and within 12 months after termination
          of the Merger Agreement the Issuer enters into an agreement providing
          for an Alternative Proposal, or the Merger Agreement is terminated
          pursuant to 7.1(f) of the Merger Agreement; or 

               (ii) any third party makes an Alternative Proposal to which the
          Issuer has made a response or any third party acquires 15% or more of
          the outstanding Issuer Common Stock prior to the Company Shareholders
          Meeting, and either (A) the requisite vote of the shareholders of
          Issuer to approve the Merger is not obtained or (B) the Merger
          Agreement is terminated pursuant to Section 7.1(g) of the Merger
          Agreement where the Issuer's breach is willful and intentional or is
          terminated pursuant to Section 7.1(d) of the Merger Agreement, and in
          the case of either (A) or (B) above, within 12 months after
          termination of the Merger Agreement the Issuer enters into an
          agreement providing for an Alternative Proposal.

           (b) In the event Grantee wishes to exercise the Option at such time
     as the Option is exercisable, Grantee shall deliver written notice (the
     "Exercise Notice") to Issuer specifying its intention to exercise the
     Option, the total number of Option Shares it wishes to purchase, and a date
     and time for the closing of such purchase (a "Closing") not less than three
     nor more than 30 business days after the later of (i) the date such
     Exercise Notice is given and (ii) the expiration or termination of any
     applicable waiting period under the Hart-Scott-Rodino Antitrust
     Improvements Act of 1976, as amended (the "HSR Act").  If prior to the
     Expiration Date (as defined in Section 11 below) any person or group (other
     than Grantee or its affiliates) shall have made a bona fide proposal that
     becomes publicly disclosed, with respect to a tender offer or exchange
     offer for 50% or more of the then outstanding shares of Issuer Common Stock
     (a "Share Proposal"), a merger, consolidation, or other business
     combination (a "Merger Proposal"), or any acquisition of a material portion
     of the assets of Issuer (an "Asset Proposal"), or shall have acquired 50%
     or more of the then outstanding shares of Issuer Common Stock (a "Share
     Acquisition") , and this Option is then exercisable, then Grantee, in lieu
     of exercising the Option, shall have the right at any time on or after the
     date the Termination Fee (defined below) under the Merger Agreement becomes
     due and payable to request in 

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     writing that Issuer pay, and promptly (but in any event not more than 
     five business days) after Grantee makes such request, Issuer shall, 
     subject to Section 2(c) below, pay to Grantee by certified check, 
     official bank check or wire transfer pursuant to Grantee's instructions, 
     in cancellation of the option, an amount in cash (the "Cancellation 
     Amount") equal to (i) the lesser of
     
               (x)  the excess over the Option Price of the greater of (A) the
          last sale price of a share of Issuer Common Stock as reported on the
          Nasdaq National Market on the last trading day prior to the date of
          the Exercise Notice, or (B)(1) the highest price per share of Issuer
          Common Stock offered to be paid or paid by any such person or group
          pursuant to or in connection with a Share Proposal, a Share
          Acquisition, or a Merger Proposal, or (2) the aggregate consideration
          offered to be paid or paid in any transaction or proposed transaction
          in connection with an Asset Proposal, divided by the number of shares
          of Issuer Common Stock then outstanding, and

               (y)  $1.718 [$2.75 million divided by initial number of Option
     Shares],

     multiplied by (ii) the number of Option Shares then covered by the Option;
     provided, however, that if, prior to payment of the Cancellation Amount,
     Grantee has been paid by Issuer the termination fee described in Section
     7.2 of the Merger Agreement (the "Termination Fee"), then the Cancellation
     Amount shall be reduced (but not below zero) to the extent necessary so
     that the sum of the Termination Fee and the Cancellation Amount shall not
     exceed $3.6 million.  If all or a portion of the price per share of Issuer
     Common Stock offered, paid, or payable or the aggregate consideration
     offered, paid, or payable for the assets of Issuer, each as contemplated by
     the preceding sentence, consists of noncash consideration, such price or
     aggregate consideration shall be the cash consideration, if any, plus the
     fair market value of the noncash consideration as mutually determined by
     the investment bankers of Issuer and the investment bankers of Grantee.

          (c)  Following exercise of the Option by Grantee, in the event that
     Grantee sells, pledges, or otherwise disposes of (including, without
     limitation, by merger or exchange) any of the Option Shares (a "Sale"),
     then any Termination Fee due and payable by Issuer following such time
     shall be reduced to the extent necessary so that the sum of

               (x)  the Termination Fee and
     
               (y)  the amount received (whether in cash, loan proceeds,
          securities, or otherwise) by Grantee in such Sale less the exercise
          price of such Option Shares sold in the Sale (the "Option Share
          Profit")

     shall not exceed $3.6 million.  If Issuer has paid to Grantee the
     Termination Fee prior to the Sale, then Grantee shall immediately 
     remit to Issuer by wire transfer of immediately 

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     available funds to a bank account designated by Issuer the excess, if 
     any, of the Option Share Profit over $850,000.

     3.   PAYMENT OF OPTION PRICE AND DELIVERY OF CERTIFICATE.  Any Closings
under Section 2 of this Agreement shall be held at the principal executive
offices of Issuer, or at such other place as Issuer and Grantee may agree.  At
any Closing hereunder, (a) Grantee or its designee will make payment to Issuer
of the aggregate price for the Option Shares being so purchased by delivery of a
certified check, official bank check, or wire transfer of funds pursuant to
Issuer's instructions payable to Issuer in an amount equal to the product
obtained by multiplying the Option Price by the number of Option Shares to be
purchased, and (b) upon receipt of such payment Issuer will deliver to Grantee
or its designee (which shall be a wholly-owned subsidiary of Grantee) a
certificate or certificates representing the number of validly issued, fully
paid, and nonassessable Option Shares so purchased, in the denominations and
registered in such names (which shall be Grantee or a wholly-owned subsidiary of
Grantee) designated in writing to Issuer by Grantee.

     4.   REGISTRATION AND LISTING OF OPTION SHARES.

          (a)  Issuer agrees to use its reasonable best efforts to (i) effect as
     promptly as possible upon the request of Grantee and (ii) cause to become
     and remain effective for a period of not less than six months (or such
     shorter period as may be necessary to effect the distribution of such
     shares) the registration under the 1933 Act, and any applicable state
     securities laws, of all or any part of the Option Shares as may be
     specified in such request; provided, however, that (i) Grantee shall have
     the right to select the managing underwriter for any such offering after
     consultation with Issuer, which managing underwriter shall be reasonably
     acceptable to Issuer, and (ii) Grantee shall not be entitled to more than
     two effective registration statements hereunder.
          
          (b)  In addition to such demand registrations, if Issuer proposes to
     effect a registration of Issuer Common Stock for its own account or for the
     account of any other shareholder of Issuer (other than on Form S-4 or Form
     S-8), Issuer will give prompt written notice to all holders of Options or
     Option Shares of its intention to do so and shall use its reasonable best
     efforts to include therein all Option Shares requested by Grantee to be so
     included, provided, however, if Issuer is in registration with respect to
     an underwritten public offering of shares of Issuer Common Stock, and if in
     the good faith judgment of the managing underwriter or managing
     underwriters, or, if none, the sole underwriter, of such offering the
     inclusion of the Option Shares and any other selling shareholder's shares
     would interfere with the successful marketing of the shares of Issuer
     Common Stock, the number of Option Shares and shares of other selling
     shareholders otherwise to be covered in the registration statement
     contemplated hereby may be reduced prorata.  No registration effected under
     this Section 4(b) shall relieve Issuer of its obligations to effect demand
     registrations under Section 4(a) hereof.

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<PAGE>


          (c)  Registrations effected under this Section 4 shall be effected at
     Issuer's expense, including the reasonable fees and expenses of counsel to
     the holder of Options or Option Shares, but excluding underwriting
     discounts and commissions to brokers or dealers.  In connection with each
     registration under this Section 4, Issuer shall indemnify and hold each
     holder of Options or Option Shares participating in such offering (a
     "Holder"), its underwriters, and each of their respective affiliates
     harmless against any and all losses, claims, damage, liabilities, and
     expenses (including, without limitation, investigation expenses and fees
     and disbursements of counsel and accountants), joint or several, to which
     such Holder, its underwriters, and each of their respective affiliates may
     become subject, under the 1933 Act or otherwise, insofar as such losses,
     claims, damages, liabilities, or expenses (or actions in respect thereof)
     arise out of or are based upon an untrue statement or alleged untrue
     statement of a material fact contained in any registration statement
     (including any prospectus therein), or any amendment or supplement thereto,
     or arise out of or are based upon the omission or alleged omission to state
     therein a material fact required to be stated therein or necessary to make
     the statements therein not misleading, other than such losses, claims,
     damages, liabilities, or expenses (or actions in respect thereof) that
     arise out of or are based upon an untrue statement or alleged untrue
     statement of a material fact contained in written information furnished by
     a Holder to Issuer expressly for use in such registration statement. 

          (d)  In connection with any registration statement pursuant to this
     Section 4, each Holder agrees to furnish Issuer with such information
     concerning itself and the proposed sale or distribution as shall reasonably
     be required in order to ensure compliance with the requirements of the 1933
     Act.  In addition, Grantee shall indemnify and hold Issuer, its
     underwriters and each of their respective affiliates harmless against any
     and all losses, claims, damages, liabilities, and expenses (including,
     without limitation, investigation expenses and fees and disbursements of
     counsel and accountants), joint or several, to which Issuer, its
     underwriters, and each of their respective affiliates may become subject
     under the 1933 Act or otherwise, insofar as such losses, claims, damages,
     liabilities, or expenses (or actions in respect thereof) arise out of or
     are based upon an untrue statement or alleged untrue statement of a
     material fact contained in written information furnished by any Holder to
     Issuer expressly for use in such registration statement.

          (e)  Upon the issuance of Option Shares hereunder, Issuer will use its
     reasonable best efforts promptly to list such Option Shares with the Nasdaq
     National Market or on such national or other exchange on which the shares
     of Issuer Common Stock are at the time listed.

     5.   REPRESENTATIONS AND WARRANTIES OF ISSUER.  Issuer hereby represents
and warrants to Grantee as follows:


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<PAGE>


          (a)  Issuer is a corporation duly organized, validly existing, and in
     good standing under the laws of the State of Minnesota and has requisite
     power and authority to enter into and perform this Agreement.

          (b)  The execution and delivery of this Agreement and the consummation
     of the transactions contemplated hereby have been duly and validly
     authorized by the Board of Directors of Issuer, and no other corporate
     proceedings on the part of Issuer are necessary to authorize this Agreement
     or to consummate the transactions contemplated hereby.  The Board of
     Directors of Issuer has duly approved the issuance and sale of the Option
     Shares, upon the terms and subject to the conditions contained in this
     Agreement, and the consummation of the transactions contemplated hereby. 
     This Agreement has been duly and validly executed and delivered by Issuer
     and, assuming this Agreement has been duly and validly authorized,
     executed, and delivered by Grantee, constitutes a valid and binding
     obligation of Issuer enforceable against Issuer in accordance with its
     terms, subject to bankruptcy, insolvency, reorganization, moratorium, or
     other similar laws affecting or relating to creditors, rights generally;
     the availability of injunctive relief and other equitable remedies; and
     limitations imposed by law on indemnification for liability under federal
     securities laws.

          (c)  Issuer has taken all necessary action to authorize and reserve
     for issuance and to permit it to issue, and at all times from the date of
     this Agreement through the date of expiration of the Option will have
     reserved for issuance upon exercise of the Option, such number of
     authorized shares of Issuer Common Stock as is equal to the number of
     Option Shares (or such other amount as may be required pursuant to Section
     10 hereof), each of which, upon issuance pursuant to this Agreement and
     when paid for as provided herein, will be validly issued, fully paid, and
     nonassessable, and shall be delivered free and clear of all claims, liens,
     charges, encumbrances, and security interests and not subject to any
     preemptive rights.

          (d)  The execution, delivery, and performance of this Agreement by
     Issuer and the consummation by it of the transactions contemplated hereby
     except as required by the HSR Act (if applicable), and, with respect to
     Section 4, compliance with the provisions of the 1933 Act and any
     applicable state securities laws, do not require the consent, waiver,
     approval, license, or authorization of or result in the acceleration of any
     obligation under, or constitute a default under, any term, condition, or
     provision of any charter or bylaw, or any indenture, mortgage, lien, lease,
     agreement, contract, instrument, order, judgment, ordinance, regulation, or
     decree or any restriction to which Issuer or any property of Issuer or its
     subsidiaries is bound, except where the failure to obtain such consents,
     waivers, approvals, licenses, or authorizations or where such acceleration
     or defaults could not, individually or in the aggregate, reasonably be
     expected to have a Company Material Adverse Effect.

     6.   REPRESENTATIONS AND WARRANTIES OF GRANTEE.  Grantee hereby represents
and warrants to Issuer that:

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<PAGE>

          (a)  Grantee is a corporation duly organized, validly existing, and in
     good standing under the laws of the State of Minnesota and has requisite
     power and authority to enter into and perform this Agreement.

          (b)  The execution and delivery of this Agreement and the consummation
     of the transactions contemplated hereby have been duly and validly
     authorized by the Board of Directors of Grantee, and no other corporate
     proceedings on the part of Grantee are necessary to authorize this
     Agreement or to consummate the transactions contemplated hereby.  This
     Agreement has been duly and validly executed and delivered by Grantee and,
     assuming this Agreement has been duly executed and delivered by Issuer,
     constitutes a valid and binding obligation of Grantee enforceable against
     Grantee in accordance with its terms, subject to bankruptcy, insolvency,
     reorganization, moratorium, or other similar laws affecting or relating to
     creditors' rights generally; the availability of injunctive relief and
     other equitable remedies; and limitations imposed by law on indemnification
     for liability under federal securities laws.

          (c)  Grantee or its designee is acquiring the Option and it will
     acquire the Option Shares issuable upon the exercise thereof for its own
     account and not with a view to the distribution or resale thereof in any
     manner not in accordance with applicable law.

     7.   COVENANTS OF GRANTEE.  Grantee agrees not to transfer or otherwise
dispose of the Option or the Option Shares, or any interest therein, except in
compliance with the 1933 Act and any applicable state securities law.  Grantee
further agrees to the placement of the following legend on the certificates)
representing the Option Shares (in addition to any legend required under
applicable state securities laws):

          "THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
          UNDER EITHER (1) THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"),
          OR (2) ANY APPLICABLE STATE LAW GOVERNING THE OFFER AND SALE OF
          SECURITIES.  NO TRANSFER OR OTHER DISPOSITION OF THESE SHARES, OR OF
          ANY INTEREST THEREIN, MAY BE MADE EXCEPT PURSUANT TO AN EFFECTIVE
          REGISTRATION STATEMENT UNDER THE ACT AND SUCH OTHER STATE LAWS OR
          PURSUANT TO EXEMPTIONS FROM REGISTRATION UNDER THE ACT, SUCH OTHER
          STATE LAWS, AND THE RULES AND REGULATIONS PROMULGATED THEREUNDER."

     8.   REASONABLE BEST EFFORTS.  Grantee and Issuer shall take, or cause to
be taken, all reasonable action to consummate and make effective the
transactions contemplated by this Agreement, including, without limitation,
reasonable best efforts to obtain any necessary consents of third parties and
governmental agencies and the filing by Grantee and Issuer promptly after the
date hereof of any required HSR Act notification forms and the documents
required to comply with the HSR Act.

                                       7

<PAGE>


     9.   CERTAIN CONDITIONS.  The obligation of Issuer to issue Option Shares
under this Agreement upon exercise of the Option shall be subject to the
satisfaction or waiver of the following conditions:

          (a)  any waiting periods applicable to the acquisition of the Option
     Shares by Grantee pursuant to this Agreement under the HSR Act shall have
     expired or been terminated;
          
          (b)  the representations and warranties of Grantee made in Section 6
     of this Agreement shall be true and correct in all material respects as of
     the date of the Closing for the issuance of such Option Shares; and

          (c)  no order, decree, or injunction entered by any court of competent
     jurisdiction or governmental, regulatory, or administrative agency or
     commission in the United States shall be in effect that prohibits the
     exercise of the option or acquisition of Option Shares pursuant to this
     Agreement.

     10.  ADJUSTMENTS UPON CHANGES IN CAPITALIZATION.  In the event of any
change in the number of issued and outstanding shares of Issuer Common Stock by
reason of any stock dividend, stock split, recapitalization, merger, rights
offering, share exchange, or other change in the corporate or capital structure
of Issuer, Grantee shall receive, upon exercise of the Option, the stock or
other securities, cash, or property to which Grantee would have been entitled if
Grantee had exercised the Option and had been a holder of record of shares of
Issuer Common Stock on the record date fixed for determination of holders of
shares of Issuer Common Stock entitled to receive such stock or other
securities, cash, or property at the same aggregate price as the aggregate
Option Price of the Option Shares.

     11.  EXPIRATION.  The Option shall expire at the earlier of (a) the
Effective Time (as defined in the Merger Agreement) or (b) if exercisable
pursuant to Section 2 hereof, 18 months after termination of the Merger
Agreement in accordance with the terms thereof (such expiration date is referred
to as the "Expiration Date").

     12.  GENERAL PROVISIONS.

          (a)  SURVIVAL.  All of the representations, warranties, and covenants
     contained herein shall survive each Closing and shall be deemed to have
     been made as of the date hereof and as of the date of each Closing.
          
          (b)  FURTHER ASSURANCES.  If Grantee exercises the Option, or any
     portion thereof, in accordance with the terms of this Agreement, Issuer and
     Grantee will execute and deliver all such further documents and instruments
     and use their reasonable best efforts to take all such further action as
     may be necessary in order to consummate the transactions contemplated
     thereby.


                                       8

<PAGE>


          (c)  SEVERABILITY.  It is the desire and intent of the parties that
     the provisions of this Agreement be enforced to the fullest extent
     permissible under the law and public policies applied in each jurisdiction
     in which enforcement is sought.  Accordingly, in the event that any
     provision of this Agreement would be held in any jurisdiction to be
     invalid, prohibited, or unenforceable for any reason, such provision, as to
     such jurisdiction, shall be ineffective, without invalidating the remaining
     provisions of this Agreement or affecting the validity or enforceability of
     such provision in any other jurisdiction.  Notwithstanding the foregoing,
     if such provision could be more narrowly drawn so as not be invalid,
     prohibited, or unenforceable in such jurisdiction, it shall, as to such
     jurisdiction, be so narrowly drawn, without invalidating the remaining
     provisions of this Agreement or affecting the validity or enforceability of
     such provision in any other jurisdiction.

          (d)  ASSIGNMENT.  This Agreement shall be binding on and inure to the
     benefit of the parties hereto and their respective successors and assigns;
     provided, however, that Issuer shall not be entitled to assign or otherwise
     transfer any of its rights or obligations hereunder and, prior to the
     option becoming exercisable pursuant to Section 2, this Agreement may not
     be assigned by Grantee.

          (e)  SPECIFIC PERFORMANCE.  The parties agree and acknowledge that in
     the event of a breach of any provision of this Agreement, the aggrieved
     party would be without an adequate remedy at law.  The parties therefore
     agree that in the event of a breach of any provision of this Agreement, the
     aggrieved party may elect to institute and prosecute proceedings in any
     court of competent jurisdiction to enforce specific performance or to
     enjoin the continuing breach of such provision, as well as to obtain
     damages for breach of this Agreement.  By seeking or obtaining any such
     relief, the aggrieved party will not be precluded from seeking or obtaining
     any other relief to which it may be entitled.

          (f)  AMENDMENTS.  This Agreement may not be modified, amended,
     altered, or supplemented except upon the execution and delivery of a
     written agreement executed by Grantee and Issuer.

          (g)  NOTICES.  All notices, requests, claims, demands, and other
     communications hereunder shall be in writing and shall be deemed to be
     sufficient if contained in a written instrument and shall be deemed given
     if delivered personally, telecopied, sent by nationally-recognized
     overnight courier or mailed by registered or certified mail (return receipt
     requested), postage prepaid, to the other party at the following addresses
     (or such other address for a party as shall be specified by like notice):

          If to Grantee:

               Medtronic, Inc.

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<PAGE>


               7000 Central Avenue N.E.
               Minneapolis, MN 55432

               with separate copies thereof addressed to

               Attention:     General Counsel
                              FAX:  (612) 572-5459
               and

               Attention:     Vice President and Chief Development Officer
                              FAX: (612) 572-5404

          If to Issuer:

               AVECOR Cardiovascular, Inc.
               7611 Northland Drive
               Minneapolis, MN 55428
               FAX: (612) 391-9106
               Attention:  Anthony Badolato, CEO
                                             
               with a copy to:

               Oppenheimer Wolff & Donnelly LLP
               Plaza VII Building
               45 South Seventh Street
               Minneapolis, MN 55402
               FAX: (612) 7100
               Attention:  Richard Lareau

           (h) HEADINGS.  The headings contained in this Agreement are for
     reference purposes only and shall not affect in any way the meaning or
     interpretation of this Agreement.

          (i)  COUNTERPARTS.  This Agreement may be executed in one or more
     counterparts, each of which shall be an original, but all of which together
     shall constitute one and the same agreement.

          (j)  GOVERNING LAW.  This Agreement shall be governed by and construed
     in accordance with the laws of the State of Minnesota applicable to
     contracts made and to be performed therein.

          (k)  JURISDICTION AND VENUE.  Each of Issuer and Grantee hereby agrees
     that any proceeding relating to this Agreement shall be brought in a state
     court of Minnesota.  Each of Issuer and Grantee hereby consents to personal
     jurisdiction in any such action 


                                       10

<PAGE>


     brought in any such Minnesota court, consents to service of process by 
     registered mail made upon such party and such party's agent, and waives 
     any objection to venue in any such Minnesota court or to any claim that 
     any such Minnesota court is an inconvenient forum.
     
          (l)  ENTIRE AGREEMENT.  This Agreement, the Confidentiality Agreement,
     and the Merger Agreement and any documents and instruments referred to
     herein and therein constitute the entire agreement between the parties
     hereto and thereto with respect to the subject matter hereof and thereof
     and supersede all other prior agreements and understandings, both written
     and oral, between the parties with respect to the subject matter hereof and
     thereof.  This Agreement shall be binding upon, inure to the benefit of,
     and be enforceable by the successors and permitted assigns of the parties
     hereto.  Nothing in this Agreement shall be construed to give any person
     other than the parties to this Agreement or their respective successors or
     permitted assigns any legal or equitable right, remedy, or claim under or
     in respect of this Agreement or any provision contained herein.

          (m)  EXPENSES.  Except as otherwise provided in this Agreement or the
     Merger Agreement, each party shall pay its own expenses incurred in
     connection with this Agreement.


                                       11

<PAGE>




     IN WITNESS WHEREOF, the parties have caused this Agreement to be signed by
their respective officers thereunto duly authorized as of the date first written
above.

                                   MEDTRONIC, INC.


                                   By
                                      ----------------------------------
                                      Its:  Vice President


                                   AVECOR CARDIOVASCULAR, INC.


                                   By
                                      ----------------------------------
                                      Its:  CEO


                                      12