Document:

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                                                                    EXHIBIT 10.1

                                AMENDMENT NO. 1
                           TO SHARE PURCHASE WARRANT

     This Amendment No. 1, dated as of February 13, 2001 (the "Amendment"), to
Share Purchase Warrant, dated July 1, 1998, (the "Warrant"), is entered into by
and between NMT Medical, Inc. (f/k/a Nitinol Medical Technologies, Inc.), a
Delaware corporation (the "Company"), and Fletcher Spaght, Inc., a Massachusetts
corporation (the "Holder").

                                    RECITALS
                                    --------

     WHEREAS, the Company and the Holder are parties to the Share Purchase
Warrant, dated July 1, 1998, pursuant to which the Holder is entitled to
subscribe for and purchase from the Company, upon the terms and conditions set
forth therein, at any time or from time to time until 5:00 p.m. New York City
time on February 14, 2001 (the "Expiration Date") all or any portion of 83,329
shares of common stock of the Company, par value $0.001 per share, subject to
adjustment as provided therein, at a price of $1.13 per share, subject to
adjustment as provided therein;

     WHEREAS, in consideration of certain services to be provided by the Holder
to the Company, the Company and the Holder wish to amend the Warrant to extend
the Expiration Date of the Warrant to February 14, 2003, and the Board of
Directors of the Company unanimously approved such an amendment on February 13,
2001;

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

     1.  Amendment to Expiration Date. The introductory paragraph of the
Warrant, beginning with "THIS CERTIFIES," and concluding with "has been
transferred" is amended to be deleted in its entirety and replaced with the
following:

     "THIS CERTIFIES that, for good and valuable consideration received,
     Fletcher Spaght, Inc. (the "Holder") is entitled to subscribe for and
     purchase from NMT Medical, Inc. (f/k/a Nitinol Medical Technologies, Inc.),
     a Delaware corporation (the "Company"), upon the terms and conditions set
     forth herein, at any time or from time to time until 5:00 P.M. New York
     City time on February 14, 2003 (the "Expiration Date"), all or any portion
     of 83,329 Shares of common stock of the Company, par value $0.001 per
     share, subject to adjustment as provided herein (the "Warrant Shares"), at
     an exercise price of $1.13 per share, subject to adjustment as provided
     herein (the "Exercise Price").  This Warrant shall not be redeemable by the
     Company.  The term "Shares" as used herein shall mean the Company's Shares
     of Common Stock, par value $0.001 per share.  This Warrant may be sold,
     transferred, assigned or hypothecated at any time and the term the "Holder"
     as used herein shall include any transferee to whom this Warrant has been
     transferred."
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     2.  Remaining Agreement. Except as amended hereby, the Warrant shall remain
         -------------------
in full force and effect in all respects.

     3.  Counterparts; Effectiveness. This Amendment may be signed in any number
         ---------------------------
of counterparts, all of which taken together shall constitute one agreement, and
any of the parties hereto may execute this Amendment by signing any such
counterpart.

     4.  Governing Law.  This Amendment shall be governed by and construed and
         -------------
enforced in accordance with the laws of the State of Delaware without giving
effect to the principles of conflicts of laws thereof.

        [The remainder of this page has been intentionally left blank.]

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     IN WITNESS WHEREOF, in accordance with Section 17 of the Warrant, the
parties hereto have executed this Amendment as an instrument under seal by their
duly authorized officers as of the date first written above.

                              NMT MEDICAL, INC.

                              By:  /s/ John E. Ahern
                                   -----------------
                                   John E. Ahern
                                   President and Chief Executive Officer

                              FLETCHER SPAGHT, INC.

                              By:  /s/ R. John Fletcher
                                   --------------------
                                   R. John Fletcher
                                   Chief Executive Officer

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                                                                    Exhibit 10.2

                                PROMISSORY NOTE
                                ---------------

$57,673                                                        February 13, 2001
                                                           Boston, Massachusetts

     FOR VALUE RECEIVED, Fletcher Spaght, Inc., a Massachusetts corporation (the
"Maker"), promises to pay to the order of NMT Medical, Inc., a Delaware
corporation, at 27 Wormwood Street, Boston, Massachusetts 02210-1625, or at such
other place as the holder of this Note may from time to time designate, the
principal sum of Fifty Seven Thousand Six Hundred Seventy Three Dollars
($57,673), together with all accrued but unpaid interest on the unpaid principal
balance of this Note from time to time outstanding at the rate set forth below.

     The principal amount of this Note and any interest shall be payable on or
before February 14, 2003.  This Note will bear interest on the outstanding
principal balance thereof annually from the date of this Note, at the rate of 5%
per year, until such principal balance shall have become due and payable
(whether at maturity, by acceleration or otherwise) and until such amounts are
paid in full.

     Interest on this Note shall be computed on the basis of a year of 365 days
for the actual number of days elapsed.  All payments by the Maker under this
Note shall be in immediately available funds.

     This Note shall become immediately due and payable without notice or demand
upon the occurrence at any time of any of the following events of default
(individually, "an Event of Default" and collectively, "Events of Default"):

     (1)  default in the payment or performance of this or any other liability
          or obligation of the Maker to the holder, including the payment when
          due of any principal, premium or interest under this Note;

     (2)  the liquidation, termination of existence, dissolution, insolvency or
          business failure of the Maker, or the appointment of a receiver or
          custodian for the Maker or any part of its property; or

     (3)  the institution by or against the Maker or any indorser or guarantor
          of this Note of any proceedings under the United States Bankruptcy
          Code or any other federal or state bankruptcy, reorganization,
          receivership, insolvency or other similar law affecting the rights of
          creditors generally or the making by the Maker or any indorser or
          guarantor of this Note of a composition or an assignment or trust
          mortgage for the benefit of creditors.

     Upon the occurrence of an Event of Default, the holder shall have then, or
at any time thereafter, all of the rights and remedies afforded by the Uniform
Commercial Code as from time to time in effect in The Commonwealth of
Massachusetts or afforded by other applicable law.
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     Every amount overdue under this Note shall bear interest from and after the
date on which such amount first became overdue at an annual rate which is five
(5) percentage points above the rate per year specified in the first paragraph
of this Note.  Such interest on overdue amounts under this Note shall be payable
on demand and shall accrue and be compounded monthly until the obligation of the
Maker with respect to the payment of such interest has been discharged (whether
before or after judgment).

     In no event shall any interest charged, collected or reserved under this
Note exceed the maximum rate then permitted by applicable law and if any such
payment is paid by the Maker, then such excess sum shall be credited by the
holder as a payment of principal.

     All payments by the Maker under this Note shall be made without set-off or
counterclaim and be free and clear and without any deduction or withholding for
any taxes or fees of any nature whatever, unless the obligation to make such
deduction or withholding is imposed by law.  The Maker shall pay and save the
holder harmless from all liabilities with respect to or resulting from any delay
or omission to make any such deduction or withholding required by law.

     Whenever any amount is paid under this Note, all or part of the amount paid
may be applied to principal, premium or interest in such order and manner as
shall be determined by the holder in its discretion.

     No reference in this Note to any guaranty or other document shall impair
the obligation of the Maker, which is absolute and unconditional, to pay all
amounts under this Note strictly in accordance with the terms of this Note.

     The Maker agrees to pay on demand all costs of collection, including
reasonable attorneys' fees, incurred by the holder in enforcing the obligations
of the Maker under this Note.

     No delay or omission on the part of the holder in exercising any right
under this Note shall operate as a waiver of such right or of any other right of
such holder, nor shall any delay, omission or waiver on any one occasion be
deemed a bar to or waiver of the same or any other right on any future occasion.
The Maker and every indorser or guarantor of this Note regardless of the time,
order or place of signing waives presentment, demand, protest and notices of
every kind and assents to any extension or postponement of the time of payment
or any other indulgence, to any substitution, exchange or release of collateral,
and to the addition or release of any other party or person primarily or
secondarily liable.

     This Note may be prepaid in whole or in part at any time or from time to
time upon two days' prior written notice with the consent of the holder, with
the giving of such consent to be in the sole discretion of the holder.  Any such
prepayment shall be without premium or penalty.

     None of the terms or provisions of this Note may be excluded, modified or
amended except by a written instrument duly executed on behalf of the holder
expressly referring to this Note and setting forth the provision so excluded,
modified or amended.

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     All rights and obligations hereunder shall be governed by the laws of The
Commonwealth of Massachusetts and this Note is executed as an instrument under
seal.

ATTEST: /s/ Amy Wells                           FLETCHER SPAGHT, INC.

                                                /s/ R. John Fletcher
                                                ------------------------
By: Amy Wells                                   By:  R. John Fletcher
    Executive Assistant                         Title:  Chief Executive Officer

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