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                                                                  Exhibit 10.16

                           NOTE PURCHASE AGREEMENT

     THIS NOTE PURCHASE AGREEMENT is made and entered into as of February 2, 
1999 by and between ENDOCARDIAL SOLUTIONS, INC. (the "Company"), a Delaware 
corporation, and MEDTRONIC ASSET MANAGEMENT, INC. ("Medtronic"), a Minnesota 
corporation.

                                  RECITALS

     WHEREAS, the Company desires to issue and sell to Medtronic, and 
Medtronic desires to purchase from the Company, on the terms and subject to 
the conditions set forth in this Agreement, a promissory note of even date 
herewith having a principal amount of up to $7,000,000 in the form attached 
hereto as Exhibit A (the "Note") and a Warrant to purchase shares of the 
Company's Common Stock, par value $.01 per share, in the form attached hereto 
as Exhibit B (the "Warrant").

                                  AGREEMENT

     NOW, THEREFORE, in consideration of the respective representations, 
warranties, covenants and agreements contained herein, and for other valuable 
consideration, the receipt and adequacy of which is hereby acknowledged, the 
parties hereto agree as follows:

                                  ARTICLE I
                                 DEFINITIONS

     1.1  SPECIFIC DEFINITIONS.  As used in this Agreement, the following 
terms shall have the meanings set forth or as referenced below:

     "AGREEMENT" means this Agreement and all exhibits and schedules hereto.

     "COMMON STOCK" means the shares of the Company's common stock, par value 
$.01 per share, authorized for issuance under the Company's Certificate of 
Incorporation.

     "COMPANY REPORTS" means each registration statement, report, proxy 
statement or information statement prepared by the Company since December 31, 
1996 including, without limitation, (i) the Company's Annual Reports on Form 
10-K, and (ii) the Company's Quarterly Reports on Form 10-Q, each in the form 
(including exhibits and any amendments thereto) filed with the SEC, and each 
annual and quarterly report sent to its stockholders

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     "DISTRIBUTION" shall mean the declaration or payment of any dividend on 
or in respect of any shares of any class of capital stock of the Company, 
other than dividends payable solely in shares of common stock of the Company; 
the purchase, redemption, or other retirement of any shares of any class of 
capital stock of the Company, directly or indirectly; the return of capital 
by the Company to its shareholders as such; or any other distribution on or 
in respect of any shares of any class of capital stock of the Company.

     "EXCHANGE ACT" means the Securities Exchange Act of 1934, as amended, 
and the rules and regulations promulgated thereunder.

     "FORM S-3"  means such form under the Securities Act in effect on the 
date hereof or any successor registration form under the Securities Act 
subsequently adopted by the SEC which permits inclusion or incorporation of 
substantial information by reference to other documents filed by the Company 
with the SEC.

     "HOLDER" means Medtronic or any person owning of record Registrable 
Securities that have not been sold to the public or any assignee of record of 
such Registrable Securities in accordance with Article VII hereof.

     "INDEBTEDNESS" shall mean all obligations, contingent and otherwise, 
that in accordance with generally accepted accounting principles should be 
classified upon the obligor's balance sheet as liabilities, or to which 
reference should be made by footnotes thereto, including in any event and 
whether or not so classified:  (a) all debt and similar monetary obligations, 
whether direct or indirect; (b) all liabilities secured by any mortgage, 
pledge, security interest, lien, charge or other encumbrance existing on 
property owned or acquired subject thereto, whether or not the liability 
secured thereby shall have been assumed; and (c) all guarantees, endorsements 
and other contingent obligations whether direct or indirect in respect of 
indebtedness of others, including any obligation to supply funds to or in any 
manner to invest in, directly or indirectly, the debtor, to purchase 
indebtedness, or to assure the owner of indebtedness against loss, through an 
agreement to purchase goods, supplies, or services for the purpose of 
enabling the debtor to make payment of the indebtedness held by such owner or 
otherwise, and the obligations to reimburse the issuer in respect of any 
letters of credit, but excluding all guarantees, endorsements and other 
contingent obligations which would not, in accordance with generally accepted 
accounting principles, be classified as liabilities upon the obligor's 
balance sheet.

     "INITIATING HOLDERS" means Holders of the Warrant and/or outstanding 
Registrable Securities at the time of the request for registration pursuant 
hereto, provided that the amount of the Warrant and Registrable Securities so 
held by such Holders represents more than fifty percent (50%) of the total 
of: (i) then oustanding Registrable Securities and (ii) Registrable 
Securities issuable upon the then outstanding Warrant. 

     "INVESTMENTS " shall mean all expenditures made and all liabilities 
incurred (contingently or otherwise) for the acquisition of stock or 
Indebtedness of, or for loans, advances, capital contributions or transfers 
of property to, or in respect of any guaranties (or other 

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commitments as described under Indebtedness), or obligations of, others, 
including without limitation, investments in joint ventures or limited 
partnerships.

     "KNOWLEDGE" means actual knowledge of a fact or the knowledge which such 
person could reasonably be expected to have based on reasonable inquiry.  The 
knowledge of an entity shall include the knowledge of such entity's officers.

     "LIENS" means liens, mortgages, charges, security interests, claims, 
voting trusts, pledges, encumbrances, options, assessments, restrictions, or 
third-party or spousal interests of any nature.

     "NOTE" has the meaning assigned to such term in the recitals of this 
Agreement.

     "REGISTER," and "REGISTRATION" means a registration effected by 
preparing and filing a registration statement in compliance with the 
Securities Act, and the declaration or ordering of effectiveness of such 
registration statement.

     "REGISTRABLE SECURITIES" means (i) the Shares and (ii) any shares of 
Common Stock of the Company issued (or issuable upon the conversion or 
exercise of any warrant, right or other security which is issued) as a 
dividend or other distribution with respect to, or in exchange for or in 
replacement of, the Shares.  Notwithstanding the foregoing, Registrable 
Securities shall not include any securities sold by a person to the public 
either pursuant to a registration statement or Rule 144 under the Securities 
Act or sold in a private transaction in which the transferror's rights under 
Article VII of this Agreement are not assigned.

     "REGISTRATION EXPENSES" means all expenses incurred by the Company in 
complying with Article VII hereof, including, without limitation, all 
registration and filing fees, printing expenses, fees and disbursements of 
counsel for the Company, reasonable fees and disbursements not to exceed Ten 
Thousand Dollars ($10,000) of a single special counsel for the holders of 
Registrable Securities, blue sky fees and expenses (but excluding the 
compensation of regular employees of the Company which shall be paid in any 
event by the Company).

     "SEC" means the United States Securities and Exchange Commission.

     "SECURITIES ACT" means the Securities Act of 1933, as amended.

     "SELLING EXPENSES" means all underwriting discounts and commissions 
applicable to a sale of Registrable Securities.

     "SHARES" means the shares of the Company's Common Stock issued or 
issuable upon exercise of the Warrant.

     "WARRANT" has the meaning assigned to such term in the recitals of this 
Agreement.

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     1.2  DEFINITIONAL PROVISIONS.

          (a)  The words "hereof," "herein," and "hereunder" and words of
     similar import, when used in this Agreement, shall refer to this Agreement
     as a whole and not to any particular provisions of this Agreement.

          (b)  Terms defined in the singular shall have a comparable meaning
     when used in the plural, and vice-versa.

          (c)  References to an "Exhibit" or to a "Schedule" are, unless
     otherwise specified, to one of the Exhibits or Schedules attached to or
     referenced in this Agreement, and references to an "Article" or a "Section"
     are, unless otherwise specified, to one of the Articles or Sections of this
     Agreement.

          (d)  The term "person" includes any individual, partnership, joint
     venture, corporation, trust, unincorporated organization or government or
     any department or agency thereof.

                                  ARTICLE II
                         PURCHASE OF NOTE AND WARRANT

     2.1  PURCHASE AND SALE OF NOTE.  The Company hereby issues and delivers 
to Medtronic, and Medtronic hereby purchases from the Company, the Note.

     2.2  PURCHASE AND SALE OF WARRANT.  The Company hereby issues and 
delivers to Medtronic, and Medtronic hereby purchases from the Company, the 
Warrant.

     2.3  PURCHASE PRICE.  The purchase price for the Note and the Warrant 
shall be an amount equal to $3,500,000, payable upon signature of this 
Agreement by wire transfer of immediately available funds to the Company's 
account designated by the Company to Medtronic.  Medtronic shall be obligated 
to advance up to an additional $3,500,000 to the Company within thirty (30) 
days following receipt of the Company's written request for such funds, 
provided that the written request for such advance is received by Medtronic 
prior to the close of business on December 31, 1999 and the Note is not then 
in default and no event has occurred which with notice or the passage of time 
would result in a default under the Note.

                                 ARTICLE III
                REPRESENTATIONS AND WARRANTIES OF THE COMPANY

     The Company represents and warrants to Medtronic as follows:

     3.1  ORGANIZATION, QUALIFICATIONS AND CORPORATE POWER.  The Company is a 
corporation duly incorporated, validly existing and in good standing under 
the laws of the State of Delaware and is duly licensed or qualified to 
transact business as a foreign 

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corporation and is in good standing in each jurisdiction in which the nature 
of the business transacted by it or the character of the properties owned or 
leased by it requires such licensing or qualification and where the failure 
to be so licensed or qualified could have material adverse effect upon the 
Company or its business.  The Company has the corporate power and authority 
to own and hold its properties and to carry on its business as now conducted 
and as proposed to be conducted, to execute, deliver and perform this 
Agreement, and to issue, sell and deliver the Shares.  The Company has no 
subsidiaries.

     3.2  AUTHORIZATION OF AGREEMENT, ETC.

          (a)  The execution and delivery by the Company of this Agreement, the
     performance by the Company of its obligations hereunder, and the issuance,
     sale and delivery of the Note and the Warrant have been duly authorized by
     all requisite corporate action and will not violate any provision of law,
     any order of any court or other agency of government, the Certificate of
     Incorporation or the By-laws of the Company, in each case as amended, or
     any provision of any material indenture, agreement or other instrument to
     which the Company or any of its properties or assets is bound, or conflict
     with, result in a breach of or constitute (with due notice or lapse of time
     or both) a default under any such material indenture, agreement or other
     instrument, or result in the creation or imposition of any material Lien
     upon any of the properties or assets of the Company.

          (b)  The shares issuable upon exercise of the Warrant have been duly
     reserved for issuance and, if and when so issued and paid for in accordance
     with this Agreement and the Warrant,  will be duly authorized, validly
     issued, fully paid and nonassessable shares of the Company's Common Stock
     and will be free and clear of all Liens imposed by or through the Company.

     3.3  VALIDITY.  This Agreement, the Note and the Warrant have been duly 
executed and delivered by the Company and constitute the legal, valid and 
binding obligations of the Company, enforceable in accordance with their 
terms, subject, as to the enforcement of remedies, to the discretion of the 
courts in awarding equitable relief and to applicable bankruptcy, 
reorganization, insolvency, moratorium and similar laws affecting the rights 
of creditors generally.

     3.4  SEC DOCUMENTS.  The Company has delivered or made available to 
Medtronic for its inspection all of the Company Reports.  As of their 
respective dates, the Company Reports (x) were prepared in all material 
respects in accordance with the applicable requirements of the Securities 
Act, the Exchange Act, and the rules and regulations thereunder and (y) did 
not contain any untrue statement of a material fact or omit to state a 
material fact required to be stated therein or necessary to make the 
statements made therein, in the light of the circumstances under which they 
were made, not misleading.  Each of the balance sheets of the Company 
included in or incorporated by reference into the Company Reports (including 
the related notes and schedules) fairly presents the financial position of 
the Company as of its date and each of the statements of income, retained 
earnings and cash flows of the Company included in or incorporated by 
reference into the Company Reports (including any related notes and 
schedules) fairly presents the results of operations, retained earnings or 
cash flows, as the case may be, of 

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the Company for the periods set forth therein (subject, in the case of 
unaudited statements, to normal year-end audit adjustments which would not be 
material in amount or effect), in each case in accordance with generally 
accepted accounting principles consistently applied during the periods 
involved, except as may be noted therein.

                                  ARTICLE IV
                 REPRESENTATIONS AND WARRANTIES OF MEDTRONIC

     Medtronic represents and warrants to the Company as follows:

     4.1  ACCREDITED STATUS.  Medtronic is an "accredited investor" within 
the meaning of Rule 501 under the Securities Act and was not organized for 
the specific purpose of acquiring the Note and the Warrant.  Medtronic has 
sufficient knowledge and experience in investing in companies similar to the 
Company in terms of the Company's stage of development so as to be able to 
evaluate the risks and merits of Medtronic's investment in the Company and 
Medtronic is able financially to bear the risks thereof.  Medtronic, in its 
capacity as a shareholder of the Company, has had an opportunity to discuss 
the Company's business, management and financial affairs with the Company's 
management.  The Note and the Warrant are being acquired for Medtronic's own 
account for the purpose of investment and not with a view to or for sale in 
connection with any distribution thereof.  Medtronic understands that (i) 
neither the Note, the Warrant nor the Shares have been registered under the 
Securities Act by reason of their issuance or, with respect to the Shares, 
anticipated issuance, in a transaction exempt from the registration 
requirements of the Securities Act pursuant to Section 4(2) thereof or 
Regulation D promulgated under the Securities Act, (ii) the Note and the 
Warrant must be held indefinitely unless a subsequent disposition thereof is 
registered under the Securities Act or is exempt from such registration and 
(iii) the Note and Warrant will bear a legend to such effect.

     4.2  CORPORATE AUTHORITY.  The execution, delivery and performance by 
Medtronic of this Agreement and the transactions contemplated hereby has been 
duly and validly authorized and approved by all requisite corporate action on 
the part of Medtronic, and the execution and the delivery of this Agreement 
and consummation of the transactions contemplated hereby and compliance with 
and fulfillment of the terms and provisions hereof will not (i) conflict with 
or result in a breach of the terms, conditions or provisions of or constitute 
a default under the Articles of Incorporation or Bylaws of Medtronic, or (ii) 
require any affirmative approval, consent, authorization or other order or 
action of any court, governmental authority, regulatory body, creditor or any 
other person.  Medtronic has all requisite power and authority to do and 
perform all acts and things required to be done by it under this Agreement 
and the agreements contemplated hereby.  This Agreement constitutes the valid 
and binding obligation of Medtronic enforceable in accordance with its terms 
subject, as to the enforcement of remedies, to the discretion of the courts 
in awarding equitable relief and to applicable bankruptcy, reorganization, 
insolvency, moratorium and similar laws affecting the rights of creditors 
generally.

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                                   ARTICLE V
                                   COVENANTS

     The Company covenants and agrees that for so long as the Note is 
outstanding:

     5.1  RESTRICTIONS ON INVESTMENTS. Except as set forth in SCHEDULE 5.1 
hereto, the Company will not permit to exist or to remain outstanding any 
Investment except Investments in:

          a)   marketable direct or guaranteed obligations of the United States
          of America that mature within two (2) years from the date of purchase;

          b)   demand deposits, certificates of deposit, bankers acceptances and
          time deposits of United States banks having total assets in excess of
          $1,000,000,000, provided that none of the foregoing shall have a term
          of more than two (2) years from the date of purchase; and

          c)   securities commonly known as "commercial paper" issued by a
          corporation organized and existing under the laws of the United States
          of America or any state thereof with a term of not more than two (2)
          years that at the time of purchase have been rated and the ratings for
          which are not less than "P 1" if rated by Moody's Investors Services,
          Inc., and not less than "A 1" if rated by Standard and Poor's.


     5.2  RESTRICTIONS ON INDEBTEDNESS. The Company will not create, incur, 
assume, guarantee or be or remain liable, contingently or otherwise, with 
respect to any Indebtedness other than:

          a)   Indebtedness to Medtronic arising under this Note or otherwise;

          b)   existing debt and lease financing facilities of the Company
          listed on SCHEDULE 5.2(b) attached hereto in an amount not exceeding
          the maximum amounts set forth on such Schedule and all renewals and
          refinancings thereof, or liabilities incurred in the ordinary course
          of business not incurred through (A) the borrowing of money, or (B)
          the obtaining of credit except for credit on an open account basis
          customarily extended and in fact extended in connection with normal
          purchases of goods and services;

          c)   Indebtedness in respect of taxes, assessments, governmental
          charges or levies and claims for labor, materials and supplies not yet
          due or which are being contested in good faith by appropriate
          proceedings promptly initiated and diligently conducted, if such
          reserve or other appropriate provision, if any, as shall be required
          by generally accepted accounting principles shall have been made
          therefor;

                                      -7-
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          d)   Indebtedness in respect of judgments or awards that have been in
          force for less than the applicable period for taking an appeal so long
          as execution is not levied thereunder or in respect of which the
          Company shall at the time in good faith be prosecuting an appeal or
          proceedings for review and in respect of which a stay of execution
          shall have been obtained pending such appeal or review;

          e)   endorsements for collection, deposit or negotiation and
          warranties of products or services, in each case incurred in the
          ordinary course of business; or

          g)   Indebtedness incurred in connection with the acquisition after
          the date hereof of any real or personal property in the ordinary
          course of business by the Company which is secured by a security
          interest in the acquired real or personal property, PROVIDED that the
          aggregate principal amount of such Indebtedness of the Company shall
          not exceed the aggregate amount of $2,500,000 at any one time.

          h)   Indebtedness incurred in connection with the lease of real
          property at market rates for the Company's facilities in the ordinary
          course of business.

     5.3  DISTRIBUTIONS; USE OF PROCEEDS The Company will not make any 
Distributions.  The Company will use the $7,000,000 proceeds from the sale of 
the Note and Warrant for general corporate purposes.

     5.4  RESTRICTIONS ON LIENS.  The Company will not (i) create or incur or 
suffer to be created or incurred or to exist any Liens upon any of its 
property or assets of any character whether now owned or hereafter acquired, 
or upon the income or profits therefrom; (ii) transfer any of such property 
or assets or the income or profits therefrom for the purpose of subjecting 
the same to the payment of Indebtedness or performance of any other 
obligation in priority to payment of its general creditors; (iii) acquire, or 
agree or have an option to acquire, any property or assets upon conditional 
sale or other title retention or purchase money security agreement, device or 
arrangement; (iv) suffer to exist for a period of more than thirty (30) days 
after the same shall have been incurred any Indebtedness or claim or demand 
against it that if unpaid might by law or upon bankruptcy or insolvency, or 
otherwise, be given any priority whatsoever over its general creditors; or 
(v) sell, assign, pledge or otherwise transfer any accounts, contract rights, 
general intangibles, chattel paper or instruments, with or without recourse; 
PROVIDED that the Company may create or incur or suffer to be created or 
incurred or to exist:

          a)   liens to secure taxes, assessments, other government charges and
          claims for labor, material or supplies not yet due or which are being
          contested in good faith by appropriate proceedings promptly initiated
          and diligently conducted, if such reserve or other appropriate
          provision, if any, as shall be required by generally accepted
          accounting principles shall have been made therefor;

          b)   deposits or pledges made in connection with, or to secure payment
          of, workmen's compensation, unemployment insurance, old age pensions
          or other social security obligations;

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          c)   liens on properties in respect of judgments or awards, the
          Indebtedness with respect to which is permitted by Section 5.2(d);

          d)   liens of carriers, warehousemen, mechanics and materialmen, and
          other like liens on properties in existence less than 120 days from
          the date of creation thereof in respect of obligations not overdue;

          e)   encumbrances on real estate consisting of easements, rights of
          way, zoning restrictions, restrictions on the use of real property and
          defects and irregularities in the title thereto, landlord's or
          lessor's liens under leases to which the Company is a party, and other
          minor liens or encumbrances none of which in the opinion of the
          Company interferes materially with the use of the property affected in
          the ordinary conduct of the business of the Company, which defects do
          not individually or in the aggregate have a materially adverse effect
          on the business of the Company;

          f)   Liens existing on the date hereof and listed on SCHEDULE 5.4(f)
          hereto;

          g)   purchase money security interests in or purchase money mortgages
          on real or personal property acquired after the date hereof to secure
          purchase money Indebtedness of the type and amount permitted by
          Section 5.2(g), incurred in connection with the acquisition of such
          property, which security interests or mortgages cover only the real or
          personal property so acquired; and

          h)   Liens in favor of Medtronic.

     5.5  SALE OF ASSETS.  The Company will not become a party to, or agree 
to or effect any  sale or other disposition of any assets which, together 
with all assets disposed of in the preceding twelve months, have an aggregate 
net book value of more than 10% of the Company's consolidated net tangible 
assets computed as of the end of the most recent fiscal quarter preceding 
such disposition.  Notwithstanding the foregoing, the following dispositions 
shall be permitted and shall be disregarded for purposes of determining the 
aggregate book value of assets sold or disposed of pursuant to the preceding 
sentence:

     (a)  the disposition of assets in the ordinary course of business,
          consistent with past practices;

     (b)  a disposition of assets resulting in proceeds which within the twelve
          months following such disposition are reinvested in the Company's
          business or a business related to the Company in a manner which will
          cause the reinvested proceeds to have a demonstrable benefit to the
          Company; or

     (c)  a disposition of assets resulting in proceeds which immediately after
          such disposition are used to prepay the Note at par plus accrued
          interest.

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     5.6  MERGER, CONSOLIDATION OR ACQUISITIONS. The Company will not become 
a party to or agree to or effect any merger or consolidation, asset 
acquisition or stock acquisition (other than the acquisition of assets in the 
ordinary course of business).

     5.7  SALE AND LEASEBACK.  The Company will not enter into any 
arrangement, directly or indirectly, whereby the Company shall sell or 
transfer any property owned by it in order then or thereafter to lease such 
property or lease other property that the Company intends to use for 
substantially the same purpose as the property being sold or transferred.

     5.8  CAPITAL EXPENDITURES.  The Company will not make Capital 
Expenditures in any fiscal year that exceed, in the aggregate, $2,500,000 for 
such fiscal year, provided, however, that notwithstanding this limitation the 
Company shall be entitled to make Capital Expenditures of not more than 
$3,000,000 for furniture, fixtures and leasehold improvements in connection 
with the Company's move to new facilities. 

     5.9  NOTICE OF DEFAULTS.  The Company will promptly notify Medtronic in 
writing of the occurrence of any Event of Default hereunder or any 
circumstances likely to lead to an Event of Default.

                                   ARTICLE VI
                               EVENTS OF DEFAULT

     6.1  EVENTS OF DEFAULT.  The entire outstanding principal amount of the 
Note and all accrued but unpaid interest thereon shall, at the option of 
Medtronic, become immediately due and payable upon the occurrence of any of 
the following events  (each, an "Event of Default") (whether such occurrence 
shall be voluntary or involuntary or come about or be effected by operation 
of law or otherwise):

          (a)  if the Company shall fail to pay when due any installment of
          interest on the Note, which failure has not been cured within ten (10)
          days after such due date; or 

          (b)  if the Company shall fail to pay on the maturity of the Note the
          entire unpaid principal amount of the Note together with all accrued
          and unpaid interest; or 

          (c)  if the Company shall make an assignment for the benefit of
          creditors, or admit in writing its inability to pay or generally fail
          to pay its debts as they mature or become due, or shall petition or
          apply for the appointment of a trustee or other custodian, liquidator
          or receiver of the Company or of any substantial part of the assets of
          the or shall commence any case or other proceeding relating to the
          Company under any bankruptcy, reorganization, arrangement, insolvency,
          readjustment of debt, dissolution or liquidation or similar law of any
          jurisdiction, now or hereafter in effect, or shall take any action to
          authorize or in furtherance of any of the foregoing, or if any such
          petition or application shall be filed or any 

                                      -10-
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          such case or other proceeding shall be commenced against the 
          Company and the Company shall indicate its approval thereof, consent 
          thereto or acquiescence therein; or

          (d)  if a decree or order is entered appointing any such trustee,
          custodian, liquidator or receiver or adjudicating the Company bankrupt
          or insolvent, or approving a petition in any such case or other
          proceeding, or a decree or order for relief is entered in respect of
          the Company in an involuntary case under federal bankruptcy laws as
          now or hereafter constituted; or

          (e)  if there shall remain in force, undischarged, unsatisfied and
          unstayed, for more than ten (10) days, whether or not consecutive, any
          final (as to which the time for further appeals has expired or to
          which the appeals process has been exhausted) judgment against the
          Company that, with other outstanding final judgments, undischarged,
          against the Company exceeds in the aggregate $100,000; or

          (f)  if the Company shall be in default under the terms of any
          indebtedness in excess of $100,000 or such other event has occurred
          and remains uncured for a period of ten(10) days resulting in the
          acceleration of any indebtedness in excess of $100,000; or 

          (g)  if the Company shall be indicted for a federal crime, a
          punishment for which could include the forfeiture of any assets of the
          Company having a fair market value in excess of $100,000; or 

          (h)  if the Company breaches any of its representations, warranties,
          covenants or agreements set forth herein and such breach continues
          unremedied for a period of the earlier of (i) twenty (20) days from
          the date an executive officer of the Company has actual knowledge of
          such breach or (ii) five (5) days after Medtronic has provided the
          Company with written notice of such breach, except that any such
          breach by the Company will not result in an Event of Default hereunder
          if waived by Medtronic in writing.

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                                 ARTICLE VII
                             REGISTRATION RIGHTS

     7.1  DEMAND REGISTRATIONS.

          (a)  Subject to the conditions of this Section 7.1, if the Company
          shall receive at any time after the date hereof, a written request
          from Initiating Holders that the Company file a registration statement
          under the Securities Act covering the registration of Registrable
          Securities having an aggregate price to public of at least $500,000,
          then the Company shall, within thirty (30) days of the receipt
          thereof, give written notice of such request to all Holders, and
          subject to the limitations of Section 7.1(b), effect, as soon as
          practicable, the registration under the Securities Act of all
          Registrable Securities that the Holders request to be registered.

          (b)  If the Initiating Holders intend to distribute the Registrable
          Securities covered by their request by means of an underwriting, they
          shall so advise the Company as a part of their request made pursuant
          to this Section 7.1 and the Company shall include such information in
          the written notice referred to in Section 7.1(a).  In such event, the
          right of any Holder to include his Registrable Securities in such
          registration shall be conditioned upon such Holder's participation in
          such underwriting and the inclusion of such Holder's Registrable
          Securities in the underwriting (unless otherwise mutually agreed by a
          majority in interest of the Initiating Holders and such Holder) to the
          extent provided herein.  All Holders proposing to distribute their
          securities through such underwriting shall enter into an underwriting
          agreement in customary form with the underwriter or underwriters
          selected for such underwriting by a majority in interest of the
          Initiating Holders (which underwriter or underwriters shall be
          reasonably acceptable to the Company).  Notwithstanding any other
          provision of this Section 7.1, if the underwriter advises the Company
          in writing that marketing factors require a limitation of the number
          of securities to be underwritten (including Registrable Securities)
          then the Company shall so advise all Holders of Registrable Securities
          which would otherwise be underwritten pursuant hereto, and the number
          of shares that may be included in the underwriting shall be allocated
          to the Holders of such Registrable Securities on a pro rata basis
          based on the number of Registrable Securities held by all Holders
          participating in the related registration (including the Initiating
          Holders).  Any Registrable Securities excluded or withdrawn from such
          underwriting shall be withdrawn from the registration.

          (c)  The Company shall not be obligated to effect more than two (2)
          registrations pursuant to this Section 7.1.

     7.2  PIGGYBACK REGISTRATIONS

          (a)  The Company shall notify all Holders of Registrable Securities in
          writing at least thirty (30) days prior to the filing of any
          registration statement under the 

                                      -12-
<PAGE>

          Securities Act for purposes of a public offering of securities of 
          the Company (including, but not limited to, registration statements 
          relating to secondary offerings of securities of the Company, but 
          excluding registration statements relating to employee benefit 
          plans and corporate reorganizations) and will afford each such 
          Holder an opportunity to include in such registration statement all 
          or part of such Registrable Securities of such Holder.  Each Holder 
          desiring to include in any such registration statement all or any 
          part of such Holder's Registrable Securities shall, within twenty 
          (20) days after receipt of the above-described notice from the 
          Company, so notify the Company in writing.  Such notice shall state 
          the intended method of disposition of the Registrable Securities by 
          such Holder.  If a Holder of Registrable Securities decides not to 
          include all of such Holder's Registrable Securities in any 
          registration statement thereafter filed by the Company, such Holder 
          shall nevertheless continue to have the right to include any 
          Registrable Securities in any subsequent registration statement or 
          registration statements as may be filed by the Company with respect 
          to offerings of its securities, all upon the terms and conditions 
          set forth herein.

          (b)  If the registration statement under which the Company gives
          notice under this Section 7.2 is for an underwritten offering, the
          Company shall so advise the Holders of Registrable Securities.  In
          such event, the right of any such Holder to be included in a
          registration pursuant to this Section 7.2 shall be conditioned upon
          such Holder's participation in such underwriting and the inclusion of
          such Holder's Registrable Securities in the underwriting to the extent
          provided herein.  All Holders proposing to distribute their
          Registrable Securities through such underwriting shall enter into an
          underwriting agreement in customary form with the underwriter or
          underwriters selected for such underwriting.  Notwithstanding any
          other provisions of this Agreement, if the underwriter determines in
          good faith that marketing factors require a limitation of the number
          of shares to be underwritten, the number of shares that may be
          included in the underwriting shall be allocated, first, to the
          Company; and second, to the Holders and any other selling shareholders
          on a pro rata basis based on the total number of securities held by
          such Holders and other selling shareholders.

     7.3  FORM S-3 REGISTRATIONS.  In case the Company shall receive from any 
Holder or Holders of Registrable Securities a written request or requests 
that the Company effect the registration under the Securities Act, and any 
related qualification or compliance with respect to, all or a part of the 
Registrable Securities owned by such Holder or Holders by the filing with the 
SEC of a registration statement on Form S-3 covering such Registrable 
Securities, the Company will:

          (a)  promptly give written notice of the proposed registration, and
          any related qualification or compliance, to all other Holders of
          Registrable Securities; and

          (b)  as soon as practicable, effect such registration and all such
          qualifications and compliances as may be so requested and as would
          permit or facilitate the sale and distribution of all or such portion
          of such Holder's or Holders' Registrable 

                                      -13-
<PAGE>

          Securities as are specified in such request, together with all or 
          such portion of the Registrable Securities of any other Holder or 
          Holders joining in such request as are specified in a written 
          request given within fifteen (15) days after receipt of such 
          written notice from the Company; provided, however, that the 
          Company shall not be obligated to effect any such registration, 
          qualification or compliance pursuant to this Section 7.3: (i) if 
          Form S-3 under the Securities Act is not available for such 
          offering by the Holders, (ii) if the Holders, together with the 
          holders of any other securities of the Company entitled to 
          inclusion in such registration, propose to sell Registrable 
          Securities and such other securities (if any) at an aggregate price 
          to the public of less than $500,000, (iii) if the Company shall 
          furnish to the Holders a certificate signed by the Chief Executive 
          Officer stating that in the good faith judgment of the Board, it 
          would be seriously detrimental to the Company and its shareholders 
          for such registration to be effected at such time, in which event 
          the Company shall have the right to defer the filing of the Form 
          S-3 registration statement for a period of not more than one 
          hundred twenty (120) days after receipt of the request of the 
          Holder or Holders under this Section 7.3, (iv) if the Company has 
          already effected two (2) registrations for the Holders pursuant to 
          this Section 7.3, or (v) in any particular jurisdiction in which 
          the Company would be required to qualify to do business or to 
          execute a general consent to service of process in effecting such 
          registration, qualification or compliance.

          (c)  Subject to the foregoing, the Company shall file a Form S-3
          registration statement covering the Registrable Securities and other
          securities so requested to be registered as soon as practicable after
          receipt of the request or requests of the Holders.

     7.4  EXPENSES OF REGISTRATION.  All Registration Expenses incurred in 
connection with any registration, qualification or compliance pursuant to 
Section 7.1 or any registration under Section 7.2 or Section 7.3 shall be 
borne by the Company.  All Selling Expenses incurred in connection with any 
such registration shall be borne by the holders of the securities so 
registered pro rata on the basis of the number of shares so registered.  The 
Company shall not, however, be required to pay for expenses of any 
registration proceeding begun pursuant to Section 7.1 or Section 7.3, the 
request of which has been subsequently withdrawn by the Initiating Holders 
unless (a) the withdrawal is based upon material adverse information 
concerning the Company of which the Company was aware but the Initiating 
Holders were not aware at the time of such request or (b) the Holders of a 
majority of the total of: (i) then outstanding Registrable Securities and 
(ii) Registrable Securities issuable upon exercise of the then outstanding 
Warrant, agree to forfeit their right to one requested registration pursuant 
to Section 7.1 or Section 7.3 (in which event such right shall be forfeited 
by all Holders).  If the Holders are required to pay the Registration 
Expenses, such expenses shall be borne by the holders of securities 
(including Registrable Securities) requesting such registration in proportion 
to the number of shares for which registration was requested.  If the Company 
is required to pay the Registration Expenses of a withdrawn offering pursuant 
to this Section 7.4, then the Holders shall not forfeit their rights pursuant 
to Section 7.1 or Section 7.3 to a demand registration.

                                      -14-
<PAGE>

     7.5  OBLIGATIONS OF THE COMPANY.  Whenever required to effect the 
registration of any Registrable Securities, the Company shall, as 
expeditiously as reasonably possible:

          (a)  Prepare and file with the SEC a registration statement on Form 
          S-3 (or such other Form as is then available to the Company in
          connection with such registration) with respect to such Registrable
          Securities and use its best efforts to cause such registration
          statement to become effective, and, upon the request of the Holders of
          a majority of the Registrable Securities registered thereunder, keep
          such registration statement effective for up to one year.

          (b)  Prepare and file with the SEC such amendments and supplements to
          such registration statement and the prospectus used in connection with
          such registration statement as may be necessary to comply with the
          provisions of the Securities Act with respect to the disposition of
          all securities covered by such registration statement.

          (c)  Furnish to the Holders such number of copies of a prospectus,
          including a preliminary prospectus, in conformity with the
          requirements of the Securities Act, and such other documents as they
          may reasonably request in order to facilitate the disposition of
          Registrable Securities owned by them.

          (d)  Use its best efforts to register and qualify the securities
          covered by such registration statement under such other securities or
          Blue Sky laws of such jurisdictions as shall be reasonably requested
          by the Holders, provided that the Company shall not be required in
          connection therewith or as a condition thereto to qualify to do
          business or to file a general consent to service of process in any
          such states or jurisdictions.

          (e)  In the event of any underwritten public offering, enter into and
          perform its obligations under an underwriting agreement, in usual and
          customary form, with the managing underwriter(s) of such offering. 
          Each Holder participating in such underwriting shall also enter into
          and perform its obligations under such an agreement.

          (f)  Notify each Holder of Registrable Securities covered by such
          registration statement at any time when a prospectus relating thereto
          is required to be delivered under the Securities Act of the happening
          of any event as a result of which the prospectus included in such
          registration statement, as then in effect, includes an untrue
          statement of a material fact or omits to state a material fact
          required to be stated therein or necessary to make the statements
          therein not misleading in the light of the circumstances then
          existing.

          (g)  Furnish, at the request of a majority of the Holders
          participating in the registration, on the date that such Registrable
          Securities are delivered to the underwriters for sale, if such
          securities are being sold through underwriters, or, if such securities
          are not being sold through underwriters, on the date that the

                                      -15-
<PAGE>

          registration statement with respect to such securities becomes
          effective, (i) an opinion, dated as of such date, of the counsel
          representing the Company for the purposes of such registration, in
          form and substance as is customarily given to underwriters in an
          underwritten public offering and reasonably satisfactory to a majority
          in interest of the Holders requesting registration, addressed to the
          underwriters, if any, and to the Holders requesting registration of
          Registrable Securities and (ii) a letter dated as of such date, from
          the independent certified public accountants of the Company, in form
          and substance as is customarily given by independent certified public
          accountants to underwriters in an underwritten public offering and
          reasonably satisfactory to a majority in interest of the Holders
          requesting registration, addressed to the underwriters, if any, and to
          the Holders requesting registration of Registrable Securities.

     7.6  TERMINATION OF REGISTRATION RIGHTS.  All registration rights 
granted under this Article VII shall terminate and be of no further force and 
effect five (5) years after the exercise in full or expiration of the Warrant.

     7.7  DELAY OF REGISTRATION.  No Holder shall have any right to obtain or 
seek an injunction restraining or otherwise delaying any such registration as 
the result of any controversy that might arise with respect to the 
interpretation or implementation of this Article VII.

     7.8  INDEMNIFICATION.  In the event any Registrable Securities are 
included in a registration statement under Sections 7.1, 7.2 or 7.3:

          (a)  To the extent permitted by law, the Company will indemnify and
          hold harmless each Holder, the partners, officers and directors of
          each Holder and each person, if any, who controls such Holder within
          the meaning of the Securities Act or the Exchange Act, and each
          underwriter, if any, and each person, if any, who controls any
          underwriter within the meaning of the Securities Act or the Exchange
          Act, against any losses, claims, damages, or liabilities (joint or
          several) to which they may become subject under the Securities Act,
          the Exchange Act or other federal or state law, insofar as such
          losses, claims, damages or liabilities (or actions in respect thereof)
          arise out of or are based upon any of the following statements,
          omissions or violations (collectively a "Violation") by the Company:
          (i) any untrue statement or alleged untrue statement of a material
          fact contained in such registration statement, including any
          preliminary prospectus or final prospectus contained therein or any
          amendments or supplements thereto, (ii) 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,
          or (iii) any violation or alleged violation by the Company of the
          Securities Act, the Exchange Act, any state securities law or any rule
          or regulation promulgated under the Securities Act, the Exchange Act
          or any state securities law in connection with the offering covered by
          such registration statement; and the Company will reimburse each such
          Holder, partner, officer, director, underwriter and controlling person
          for any legal or other expenses reasonably incurred by them in
          connection with investigating or defending any such loss, claim,
          damage, liability or action; 

                                      -16-
<PAGE>

          provided however, that the indemnity agreement contained in this 
          Section 7.8(a) shall not apply to amounts paid in settlement of any 
          such loss, claim, damage, liability or action if such settlement is 
          effected without the consent of the Company (which consent shall 
          not be unreasonably withheld), nor shall the Company be liable in 
          any such case for any such loss, claim, damage, liability or action 
          to the extent that it arises out of or is based upon a Violation 
          which occurs in reliance upon and in conformity with written 
          information furnished expressly for use in connection with such 
          registration by such Holder, partner, officer, director, or 
          controlling person of such Holder.

          (b)  To the extent permitted by law, each selling Holder will
          indemnify and hold harmless the Company, each of its directors, each
          of its officers, each person, if any, who controls the Company within
          the meaning of the Securities Act, and each underwriter, if any, and
          each person, if any, who controls any underwriter within the meaning
          of the Securities Act or the Exchange Act, and any other Holder
          selling securities under such registration statement or any of such
          other Holder's partners, directors or officers or any person who
          controls such Holder, against any losses, claims, damages or
          liabilities (joint or several) to which the Company or any such
          director, officer, underwriter, controlling person, or other such
          Holder, or partner, director, officer or controlling person of such
          other Holder may become subject under the Securities Act, the Exchange
          Act or other federal or state law, insofar as such losses, claims,
          damages or liabilities (or actions in respect thereto) arise out of or
          are based upon any Violation, in each case to the extent (and only to
          the extent) that such Violation occurs in reliance upon and in
          conformity with written information furnished by such Holder and
          stated to be specifically for use in connection with such
          registration; and each such Holder will reimburse any legal or other
          expenses reasonably incurred by the Company or any such director,
          officer, underwriter, controlling person, or other Holder, or partner,
          officer, director or controlling person of such other Holder in
          connection with investigating or defending any such loss, claim,
          damage, liability or action if it is judicially determined that there
          was such a Violation; provided, however, that the indemnity agreement
          contained in this Section 7.8(b) shall not apply to amounts paid in
          settlement of any such loss, claim, damage, liability or action if
          such settlement is effected without the consent of the Holder, which
          consent shall not be unreasonably withheld; provided further that in
          no event shall any indemnity under this Section 7.8(b) exceed the
          gross proceeds from the offering received by such Holder unless the
          Violation is the result of fraud on the part of such Holder.

          (c)  Promptly after receipt by an indemnified party under this Section
          7.8 of notice of the commencement of any action (including any
          governmental action), such indemnified party will, if a claim in
          respect thereof is to be made against any indemnifying party under
          this Section 7.8, deliver to the indemnifying party a written notice
          of the commencement thereof and the indemnifying party shall have the
          right to participate in, and, to the extent the indemnifying party so
          desires, jointly with any other indemnifying party similarly noticed,
          to assume the 

                                      -17-
<PAGE>

          defense thereof with counsel mutually satisfactory to the parties; 
          provided, however, that an indemnified party shall have the right 
          to retain its own counsel, with the fees and expenses to be paid by 
          the indemnifying party provided however, that if there is more than 
          one indemnified party, the indemnifying party shall pay for the 
          fees and expenses of one counsel for any and all indemnified 
          parties to be mutually agreed upon by such indemnified parties, if 
          representation of such indemnified party by the counsel retained by 
          the indemnifying party would be inappropriate due to actual or 
          potential differing interests between such indemnified party and 
          any other party represented by such counsel in such proceeding.  
          The failure to deliver written notice to the indemnifying party 
          within a reasonable time of the commencement of any such action, if 
          materially prejudicial to its ability to defend such action, shall 
          relieve such indemnifying party of any liability to the indemnified 
          party under this Section 7.8, but the omission so to deliver 
          written notice to the indemnifying party will not relieve it of any 
          liability that it may have to any indemnified party otherwise than 
          under this Section 7.8.

          (d)  If the indemnification provided for in this Section 7.8 is held
          by a court of competent jurisdiction to be unavailable to an
          indemnified party with respect to any losses, claims, damages or
          liabilities referred to herein, the indemnifying party, in lieu of
          indemnifying such indemnified party thereunder, shall to the extent
          permitted by applicable law contribute to the amount paid or payable
          by such indemnified party as a result of such loss, claim, damage or
          liability in such proportion as is appropriate to reflect the relative
          fault of the indemnifying party on the one hand and of the indemnified
          party on the other in connection with the Violation(s) that resulted
          in such loss, claim, damage or liability, as well as any other
          relevant equitable considerations.  The relative fault of the
          indemnifying party and of the indemnified party shall be determined by
          a court of law by reference to, among other things, whether the untrue
          or alleged untrue statement of a material fact or the omission to
          state a material fact relates to information supplied by the
          indemnifying party or by the indemnified party and the parties'
          relative intent, knowledge, access to information and opportunity to
          correct or prevent such statement or omission.

          (e)  The foregoing indemnity agreements of the Company and Holders are
          subject to the condition that, insofar as they relate to any Violation
          made in a preliminary prospectus but eliminated or remedied in the
          amended prospectus on file with the SEC at the time the registration
          statement in question becomes effective or the final prospectus filed
          with the SEC pursuant to SEC Rule 424(b), such indemnity agreement
          shall not inure to the benefit of any person if a copy of such final
          prospectus was furnished to the indemnified party and was not
          furnished to the person asserting the loss, liability, claim or damage
          at or prior to the time such action is required by the Securities Act.

                                      -18-
<PAGE>

          (f)  The obligations of the Company and Holders under this Section 7.8
          shall survive the completion of any offering of Registrable Securities
          in a registration statement, and otherwise.

     7.9  ASSIGNMENT OF REGISTRATION RIGHTS.  The rights to cause the Company 
to register Registrable Securities pursuant to this Article VII may be 
assigned by a Holder to a transferee or assignee of Registrable Securities or 
a portion of the Warrant; provided, however, that no such transferee or 
assignee shall be entitled to registration rights under this Article VII 
hereof unless it acquires Registrable Securities, Warrants, or a combination 
thereof, that represent at least fifty thousand (50,000) shares of 
Registrable Securities (as adjusted for stock splits and combinations) and 
the Company shall, within twenty (20) days after such transfer, be furnished 
with written notice of the name and address of such transferee or assignee 
and the securities with respect to which such registration rights are being 
assigned; provided, however, that a Holder's failure to provide such notice 
to the Company shall not in any way impair a Holder's right to make an 
assignment under this Section 7.9, but until such notice is provided the 
Company may continue to treat the original Holder (and not the Holder's 
assignee) as the Holder of the registration rights. Notwithstanding the 
foregoing, rights to cause the Company to register securities may be assigned 
to any person or entity who is a subsidiary, parent, general partner or 
limited partner of a Holder regardless of the number of securities 
transferred to such person or entity.

     7.10  AMENDMENT OF REGISTRATION RIGHTS.  Any provision of this Article 
VII may be amended and the observance thereof may be waived (either generally 
or in a particular instance and either retroactively or prospectively), only 
with the written consent of the Company and the Holders of Registrable 
Securities and/or Warrant representing at least seventy percent (70%) of the 
total of: (i) then outstanding Registrable Securities and (ii) Registrable 
Securities issuable upon exercise of the then outstanding Warrant.  Any 
amendment or waiver effected in accordance with this Section 7.10 shall be 
binding upon each Holder and the Company.  By acceptance of any benefits 
under this Article VII, Holders of Registrable Securities hereby agree to be 
bound by the provisions hereunder.

     7.11  LIMITATION ON SUBSEQUENT REGISTRATION RIGHTS.  From and after the 
date of this Agreement, the Company shall not, without the prior written 
consent of the Holders of at least a majority of the total of: (i) then 
outstanding Registrable Securities and (ii) Registrable Securities issuable 
upon exercise of the then outstanding Warrant, enter into any agreement with 
any person or persons providing for the granting to such holder of 
registration rights pari passu or senior to those granted to Holders pursuant 
to this Article VII, or of registration rights which might cause a reduction 
in the number of shares includable by the Holders in any offering pursuant to 
Section 7.1 or in any offering subject to Section 7.2.

     7.12  REGISTRATION RIGHTS SEPARATE FROM OTHER REGISTRATION RIGHTS.  The 
registration rights granted to any Holder hereunder shall be deemed to be 
separate and distinct from any other registration rights (the "Other 
Registration Rights") granted by the Company to any such Holders or any other 
holder of the Company's securities, including without limitation, 
registration rights granted by the Company to holders of its securities 
pursuant to the Amended and Restated Investors' Rights Agreement dated as of 
January 31, 1995, as amended 

                                      -19-
<PAGE>

April 26, 1996, between the Company and the purchasers of the Company's 
Series A Preferred Stock and Series B Preferred Stock identified on the 
signature pages thereto; the Investment Agreement dated April 26, 1996 
between the Company and Medtronic; the Stock Purchase Agreement dated March 
18, 1997 between the Company and Medtronic; and the Registration Rights 
Agreement dated January 30, 1998 by and between the Company and Medtronic.  
In addition, any registration of Registrable Securities pursuant to the 
rights granted hereunder shall not affect the rights of any Holder or any 
other person under the Other Registration Rights, and any registration of the 
Company's securities under the Other Registration Rights shall not affect the 
rights of any Holder of Registrable Securities hereunder.

                                 ARTICLE VIII
                               INDEMNIFICATION

     8.1  INDEMNIFICATION OF MEDTRONIC.  The Company shall indemnify, defend 
and hold harmless Medtronic and each of its subsidiaries, officers, directors 
and stockholders (Medtronic and such other indemnitees referred to in this 
Article VIII as "Medtronic") from and against and in respect of any and all 
demands, claims, actions or causes of action, assessments, losses, damages, 
liabilities, interest and penalties, costs and expenses (including, without 
limitation, reasonable legal fees and disbursements incurred in connection 
therewith and in seeking indemnification therefor, and any amounts or 
expenses required to be paid or incurred in connection with any action, suit, 
proceeding, claim, appeal, demand, assessment or judgment) ("Indemnifiable 
Losses"), resulting from, arising out of, or imposed upon or incurred by any 
person to be indemnified hereunder by reason of any breach of any 
representation, warranty, covenant or agreement of the Company contained in 
this Agreement or any agreement, certificate or document executed and 
delivered by the Company pursuant hereto or in connection with any of the 
transactions contemplated by this Agreement.

     8.2  INDEMNIFICATION OF THE COMPANY.  Medtronic shall indemnify, defend 
and hold harmless the Company and each of its subsidiaries, officers, 
directors and stockholders (the Company and such other indemnitees referred 
to in this Article VIII as the "Company") from and against and in respect of 
any and all demands, claims, actions or causes of action, assessments, 
losses, damages, liabilities, interest and penalties, costs and expenses 
(including, without limitation, reasonable legal fees and disbursements 
incurred in connection therewith and in seeking indemnification therefor, and 
any amounts or expenses required to be paid or incurred in connection with 
any action, suit, proceeding, claim, appeal, demand, assessment or judgment), 
resulting from, arising out of, or imposed upon or incurred by any person to 
be indemnified hereunder by reason of any breach of any representation, 
warranty, covenant or agreement of Medtronic contained in this Agreement or 
any agreement, certificate or document executed and delivered by Medtronic 
pursuant hereto or in connection with the transactions contemplated by this 
Agreement.

     8.3  THIRD-PARTY CLAIMS.  If a claim by a third party is made against an 
indemnified party and if the indemnified party intends to seek indemnity with 
respect thereto under this Article VIII, such indemnified party shall 
promptly notify the indemnifying party of such claim; provided, however, that 
failure to give timely notice shall not affect the rights of the indemnified 

                                      -20-
<PAGE>

party so long as the failure to give timely notice does not adversely affect 
the indemnifying party's ability to defend such claim against a third party.  
The indemnified party shall not settle such claim without the consent of the 
indemnifying party, which consent shall not be unreasonably withheld or 
delayed.  If the indemnifying party acknowledges in writing its indemnity 
obligations for Indemnifiable Losses resulting therefrom, the indemnifying 
party may participate at its own cost and expense in the settlement or 
defense of any claim for which indemnification is sought; PROVIDED THAT such 
settlement or defense shall be controlled by the indemnified party.

     8.4  COOPERATION AS TO INDEMNIFIED LIABILITY.  Each party hereto shall 
cooperate fully with the other parties with respect to access to books, 
records, or other documentation within such party's control, if deemed 
reasonably necessary or appropriate by any party in the defense of any claim 
which may give rise to indemnification hereunder.

                                  ARTICLE IX
                               OTHER PROVISIONS

     9.1  FURTHER ASSURANCES.  At such time and from time to time on and 
after the date hereof upon request by Medtronic, the Company will execute, 
acknowledge and deliver, or will cause to be done, executed, acknowledged and 
delivered, all such further acts, certificates and assurances that may be 
required for the better conveying, transferring, assigning, delivering, 
assuring and confirming to Medtronic, or to its respective successors and 
assigns, the Note, the Warrant and, upon exercise of the Warrant, the Shares 
or to otherwise carry out the purposes of this Agreement.

     9.2  COMPLETE AGREEMENT.  The schedules and exhibits to this Agreement 
shall be construed as an integral part of this Agreement to the same extent 
as if they had been set forth verbatim herein.  This Agreement and the 
schedules and exhibits hereto constitute the entire agreement between the 
parties hereto with respect to the subject matter hereof and supersede all 
prior agreements whether written or oral relating hereto.

     9.3  SURVIVAL OF REPRESENTATIONS, WARRANTIES AND AGREEMENTS.  The 
representations, warranties, covenants and agreements contained herein shall 
survive the purchase of the Note and the Warrant and remain in full force and 
effect.  No independent investigation of the Company by Medtronic, its 
counsel, or any of its agents or employees shall in any way limit or restrict 
the scope of the representations and warranties made by the Company in this 
Agreement.

     9.4  WAIVER, DISCHARGE, AMENDMENT, ETC.  The failure of any party hereto 
to enforce at any time any of the provisions of this Agreement shall not, 
absent an express written waiver signed by the party making such waiver 
specifying the provision being waived, be construed to be a waiver of any 
such provision, nor in any way to affect the validity of this Agreement or 
any part thereof or the right of the party thereafter to enforce each and 
every such provision.  No waiver of any breach of this Agreement shall be 
held to be a waiver of any other or subsequent breach.  This Agreement may be 
amended by the Company and Medtronic, by 

                                      -21-
<PAGE>

mutual action approved by their respective Boards of Directors or their 
respective officers authorized by such Board of Directors, at any time prior 
to the Closing Date.  Any amendment to this Agreement shall be in writing and 
signed by the Company and Medtronic.

     9.5  NOTICES.  All notices or other communications to a party required 
or permitted hereunder shall be in writing and shall be delivered personally 
or by telecopy (receipt confirmed) to such party (or, in the case of an 
entity, to an executive officer of such party) or shall be sent by a 
reputable express delivery service or by certified mail, postage prepaid with 
return receipt requested, addressed as follows:

     if to Medtronic to:

          Medtronic Asset Management, Inc.
          Corporate Center
          7000 Central Avenue N.E.
          Minneapolis, Minnesota 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 the Company to:

          Endocardial Solutions, Inc.
          1350 Energy Lane, Suite 110
          St. Paul, Minnesota 55108-5254
          Attention:     James W. Bullock,
                         President and Chief Executive Officer
                         FAX (651) 644-7897

Any party may change the above-specified recipient and/or mailing address by 
notice to all other parties given in the manner herein prescribed.  All 
notices shall be deemed given on the day when actually delivered as provided 
above (if delivered personally or by telecopy) or on the day shown on the 
return receipt (if delivered by mail or delivery service).

     9.6  PUBLIC ANNOUNCEMENT.  In the event any party proposes to issue any 
press release or public announcement concerning any provisions of this 
Agreement or the transactions contemplated hereby, such party shall so advise 
the other parties hereto, and the parties shall thereafter use their best 
efforts to cause a mutually agreeable release or announcement to be issued.  
Neither party will publicly disclose or divulge any provisions of this 
Agreement or the transactions contemplated hereby without the other parties' 
written consent, except as may be required by applicable law or stock 
exchange regulation, and except for communications to employees.

                                      -22-
<PAGE>

     9.7   EXPENSES.  Except as otherwise provided in this Agreement, the 
Company and Medtronic shall each pay their own expenses incident to this 
Agreement and the preparation for, and consummation of, the transactions 
provided for herein.

     9.8   GOVERNING LAW.  This Agreement shall be governed by and interpreted 
in accordance with the laws of the State of Minnesota, including all matters 
of construction, validity, performance and enforcement, without giving effect 
to principles of conflict of laws.

     9.9   TITLES AND HEADINGS; CONSTRUCTION.  The titles and headings to the 
Articles and Sections herein are inserted for the convenience of reference 
only and are not intended to be a part of or to affect the meaning or 
interpretation of this Agreement.  This Agreement shall be construed without 
regard to any presumption or other rule requiring construction hereof against 
the party causing this Agreement to be drafted.

     9.10  BENEFIT.  Nothing in this Agreement, expressed or implied, is 
intended to confer on any person other than the parties hereto or their 
respective successors or assigns, any rights, remedies, obligations or 
liabilities under or by reason of this Agreement.

     9.11  COUNTERPARTS.  This Agreement may be executed in any number of 
counterparts, each of which shall be deemed as original and all of which 
together shall constitute one instrument.

     9.12  PARTIES IN INTEREST.  All representations, covenants and agreements 
contained in this Agreement by or on behalf of any of the parties hereto 
shall bind and inure to the benefit of the respective successors and assigns 
of the parties hereto whether so expressed or not.

     IN WITNESS WHEREOF, each of the parties has caused this Agreement to be 
executed as of the date first written above.

                                       ENDOCARDIAL SOLUTIONS, INC.


                                       By   /s/ James W. Bullock
                                          ----------------------------------
                                       Name: James W. Bullock
                                       Title:    President and Chief
                                                 Executive Officer


                                       MEDTRONIC ASSET MANAGEMENT, INC.


                                       By   /s/ Michael D. Ellwein
                                          ----------------------------------
                                       Name:     Michael D. Ellwein
                                       Title:    V.P. and CDO


                                      -23-
<PAGE>

                                                                      EXHIBIT A

     THIS PROMISSORY NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 
1933, AS AMENDED, OR ANY APPLICABLE STATE LAW, AND NO INTEREST HEREIN MAY BE 
SOLD, DISTRIBUTED, ASSIGNED, OFFERED, PLEDGED OR OTHERWISE TRANSFERRED UNLESS 
(A) THERE IS AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND 
APPLICABLE STATE SECURITIES LAWS COVERING ANY SUCH TRANSACTION INVOLVING THIS 
PROMISSORY NOTE, OR (B) THE COMPANY RECEIVES AN OPINION OF LEGAL COUNSEL 
REASONABLY SATISFACTORY TO THE COMPANY STATING THAT SUCH TRANSACTION IS 
EXEMPT FROM REGISTRATION.

                                PROMISSORY NOTE

$7,000,000.00                                                  February 2, 1999

     FOR VALUE RECEIVED, the undersigned, ENDOCARDIAL SOLUTIONS, INC. 
("Maker"), promises to pay to the order of MEDTRONIC ASSET MANAGEMENT, INC. 
("Medtronic") at Medtronic's principal corporate offices, or at such other 
place as the holder hereof may from time to time designate in writing, the 
principal sum of $7,000,000.00 or so much thereof as has been advanced by 
Medtronic to or for the benefit of the Maker pursuant to that certain Note 
Purchase Agreement, dated as of the date hereof, as amended from time to 
time, between the Maker and Medtronic and remains unpaid at maturity, plus 
interest (compounded monthly) commencing on the date hereof at a rate equal 
to eight percent (8%) per annum based on the actual number of days elapsed in 
a 360-day year. Interest accruing under this Note shall be payable on each 
March 3 1, June 30, September 30 and December 31 during the term of this Note 
and at maturity or earlier prepayment in full. The entire principal amount 
and all accrued and unpaid interest hereunder shall be due and payable in 
full on the first to occur of the following: (i) the closing of any financing 
transaction, including debt or equity financing, from which Maker receives 
proceeds, after deduction of offering expenses, of $20 million or more; (ii) 
a Change of Control of Maker, as defined below; or (iii) February 2, 2001. 
Payments hereunder shall be applied first to the payment of accrued interest 
and then to the reduction of principal. Principal, interest and all other 
sums payable hereunder shall be paid in lawful money of the United States of 
America.

     For purposes of this Note, a "Change of Control of Maker" means any of 
the following events: (i) any "person" (as such term is used in Sections 
13(d) and 14(d) of the Securities Exchange Act of 1934), other than 
Medtronic, acquires "beneficial ownership" (as defined in Rule 13d-3 under 
the Securities Exchange Act of 1934), directly or indirectly, of securities 
of Maker or of an entity that directly or indirectly owns Maker, or is an 
affiliate that directly or indirectly controls Maker, (referred to as "Maker 
Parent") representing 20% or more of the combined voting power (with respect 
to the election of directors) of Maker's or Maker Parent's, as the case may 
be, then outstanding securities; (ii) the consummation of a merger, share 
exchange, combination or consolidation of Maker or Maker Parent, as the case 
may be, with or into any other corporation, which would result in the voting 
securities of Maker or Maker Parent, as the case may be, outstanding 
immediately prior thereto continuing to represent (either by remaining 
outstanding or by being converted into voting securities of the surviving 
entity) less than 80% of the combined voting power (with respect to the 
election of directors) of the securities of Maker or Maker Parent, as the 
case may be, or of such surviving entity outstanding immediately after such 
merger, share exchange, combination or consolidation; or (iii) the 
consummation of a plan of complete liquidation of Maker or Maker Parent, as 
the case may be, or (iv) the consummation of an agreement for the sale or 
disposition by Maker 

<PAGE>

or Maker Parent, as the case may be, of all or substantially all of Maker's 
or Maker Parent's, as the case may be, business or assets.

     This Note is issued in connection with that certain Note Purchase 
Agreement dated February 2, 1999 between Maker and Medtronic (the "Note 
Purchase Agreement"). This Note is subject to, among other things, the 
default provisions and rights of acceleration as provided in the Note 
Purchase Agreement upon the occurrence of an Event of Default as defined in 
the Note Purchase Agreement.

     Except as expressly set forth in the Note Purchase Agreement, Maker 
waives demand, diligence, presentment for payment, protest and demand, and 
notice of extension, dishonor, protest, demand and nonpayment of this Note. 
Maker agrees to pay all costs of collection, defense and enforcement of this 
Note and the Note Purchase Agreement, including attorneys' fees, whether suit 
is brought or not, that the holder may incur.

     This Note shall be binding upon Maker and its successors and assigns and 
shall inure to the benefit of the payee hereof, and any subsequent holders of 
this Note, and their successors and assigns. Maker may not, without the 
holder's prior written consent, assign any of its rights, powers or 
obligations under this Note. Any such consent shall not relieve Maker of 
liability for payment in the event of default by the assignee.

     This Note shall be governed by, and construed and enforced in accordance 
with, the laws of the State of Minnesota.

     IN WITNESS WHEREOF, the Maker has executed this Note and caused it to be 
dated as of the date first written above.

                                       ENDOCARDIAL SOLUTIONS, INC.



                                       By:
                                           -----------------------------------

                                       Its: 
                                            ----------------------------------