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                                   EXHIBIT 10

FOURTH AMENDMENT TO CREDIT AGREEMENT

        This FOURTH AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is made as
of April 1, 1996 between BOSTON SCIENTIFIC CORPORATION (the "Borrower"), a
Delaware corporation having its principal place of business and chief executive
office at One Boston Scientific Place, Natick, Massachusetts 01760-1537 and THE
FIRST NATIONAL BANK OF BOSTON (the "Lender"), a national bank with its head
office at 100 Federal Street, Boston, Massachusetts 02110.

WITNESSETH:

        WHEREAS, the Borrower and the Lender have heretofore entered into the
Second Amended and Restated Loan Agreement dated as of May 7, 1993, (as amended
by a First Amendment to the Credit Agreement dated as of November 1, 1993, a
Second Amendment to the Credit Agreement dated as of February 7, 1995 and a
Third Amendment to the Credit Agreement dated August 18, 1995, the "Credit
Agreement");

        WHEREAS, subject to the terms of the Credit Agreement, the Lender has
made available to the Borrower a revolving credit facility (the "Line") in the
principal amount of $60,000,000;

        WHEREAS, the Borrower has requested that the Lender temporarily increase
the maximum availability under the Line to $110,000,000; and

        WHEREAS, the Lender is willing to agree to such temporary increase
subject to the terms and conditions set forth herein;

        NOW THEREFORE, in consideration of the premises and for good and
valuable consideration, the receipt and sufficiency of which are hereby mutually
acknowledged, the parties hereto agree as follows:

        Section 1. DEFINITIONS. All capitalized terms used herein which are
defined in the Credit Agreement shall have the same meanings herein as therein,
except as otherwise specifically provided herein.

        Section 2. AMENDMENTS TO THE CREDIT AGREEMENT. From and after the date
hereof, the Credit Agreement is hereby amended as follows:

        2.1. The definition "Maximum Amount" set forth in Section I of the
Credit Agreement is hereby deleted in its entirety, and the following
substituted therefor:

                "Maximum Amount", unless otherwise reduced by the Borrower
pursuant to Section 2.7 hereof, shall mean (i) $110,000,000 for the period from
April 1, 1996 to June 17, 1996, and (ii) $60,000,000 for all other times."
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        2.2. The second sentence of Section 2.1 of the Credit Agreement is
hereby deleted in its entirety, and the following substituted therefor:

         "The Borrower agrees that if at any time the debit balance of the Loan
         Account plus the aggregate face amount of Letters of Credit outstanding
         at any time shall exceed the Maximum Amount, the Borrower shall
         immediately pay cash to the Lender to be credited to the Loan Account
         in such amount as may be necessary to eliminate the excess."

        Section 3.  GENERAL.

        3.1. The Borrower represents and warrants that no event has occurred and
is continuing and no condition exists which constitutes or, with the passage of
time or the giving of notice, or both, would constitute an Event of Default
under the Credit Agreement, as amended hereby, except to the extent previously
waived by the Lender in writing.

        3.2. This Amendment may be executed in any number of counterparts, each
of which when executed and delivered shall be deemed an original, but all of
which together shall constitute one instrument. In making proof of this
Amendment, it shall not be necessary to produce or account for more than one
counterpart hereof signed by each of the parties hereto. This Amendment is
expressly made supplemental to and a part of the Credit Agreement and, except to
the extent specifically amended hereby, all of the terms, conditions and
provisions of the Credit Agreement shall remain unmodified, and the Credit
Agreement as amended hereby is confirmed as being in full force and effect.

        IN WITNESS WHEREOF, the parties hereto have executed this Amendment
under seal as of the day first written by their respective officers hereunto
duly authorized.

                                        BOSTON SCIENTIFIC CORPORATION



                                        By: /S/ Lawrence C. Best
                                           ----------------------------------
                                        Name:  Lawrence C. Best
                                        Title: Chief Financial Officer


                                        THE FIRST NATIONAL BANK OF BOSTON


                                        By: /S/ Timothy G. Clifford
                                           ----------------------------------
                                        Name:  Timothy G. Clifford
                                        Title: Vice President


