<PAGE>
                                                                   Exhibit 10.1
                                                                 CONFORMED COPY


                      AMENDED AND RESTATED CREDIT AGREEMENT


         AMENDED AND RESTATED CREDIT AGREEMENT dated as of August 22, 2001 among
GUIDANT CORPORATION, the BANKS listed on the signature pages hereof and MORGAN
GUARANTY TRUST COMPANY OF NEW YORK, as Administrative Agent.


                              W I T N E S S E T H :


         WHEREAS, certain of the parties hereto have heretofore entered into a
364-Day Credit Agreement dated as of August 23, 2000 (the "AGREEMENT");

         WHEREAS, at the date hereof, there are no Loans outstanding under the
Agreement; and

         WHEREAS, the parties hereto desire to amend the Agreement as set forth
herein and to restate the Agreement in its entirety to read as set forth in the
Agreement with the amendments specified below;

         NOW, THEREFORE, the parties hereto agree as follows:

Section 1 . Definitions; References. Unless otherwise specifically defined
herein, each capitalized term used herein which is defined in the Agreement
shall have the meaning assigned to such term in the Agreement. Each reference to
"hereof", "hereunder", "herein" and "hereby" and each other similar reference
and each reference to "this Agreement" and each other similar reference
contained in the Agreement shall from and after the date hereof refer to the
Agreement as amended and restated hereby. The term "NOTES" defined in the
Agreement shall include from and after the date hereof the New Notes (as defined
below).

         Section 2 . Extension Of The Facility. The definition of Termination
Date in Section 1.01 is amended to read as follows:

         "TERMINATION DATE" means August 21, 2002, or, if such day is not a
Euro-Dollar Business Day, the next preceding Euro-Dollar Business Day.

         Section 3 . Updated Representations.

         (a) Each reference to "1999" in the definition of Borrower's 1999 Form
10-K and in Section 4.04(a) and Section 4.05 is changed to "2000".


<PAGE>

         (b) Each reference to "2000" in the definition of Borrower's Latest
Form 10-Q and in Section 4.04(b) and (c) is changed to "2001".

         Section 4 . Covenant Amendments.

         (a) The figure "$780,500,000" in Section 5.09 is changed to
"$1,079,000,000".

         (b) Each reference to "2000" in Section 5.09 is changed to "2001".

         Section 5 . Maximum Commitment Increase. The figure "$400,000,000" in
Section 2.02(a) is changed to "$600,000,000".

         Section 6 . Change In Commitments. With effect from and including the
date this Amendment and Restatement becomes effective in accordance with Section
10 hereof, (i) each Person listed on the signature pages hereof which is not a
party to the Agreement (a "NEW BANK") shall become a Bank party to the Agreement
and (ii) the Commitment of each Bank shall be the amount set forth opposite the
name of such Bank on the attached Commitment Schedule, which shall replace the
existing Commitment Schedule. Any Bank whose Commitment is changed to zero shall
upon such effectiveness cease to be a Bank party to the Agreement, and all
accrued fees and other amounts payable under the Agreement for the account of
such Bank shall be due and payable on such date; provided that the provisions of
Sections 8.03, 8.04 and 9.03 of the Agreement shall continue to inure to the
benefit of each such Bank.

         Section 7 . Changes In Agents.

         (a) The reference to "J.P. Morgan Securities Inc. Arranger" on the
cover page is amended to read "The Chase Manhattan Bank Lead Arranger".

         (b) The reference to "Bank of America, N.A." and "The Chase Manhattan
Bank, Co-Documentation and Co-Syndication Agents" on the cover page is amended
to read "Bank of America, N.A., The Bank of Tokyo-Mitsubishi, Ltd., Citicorp
USA, Inc. and Credit Suisse First Boston, Syndication Agents".

         (c) The reference to "Bank One, Indiana, NA" and "Citibank, N.A.,
Senior Managing Agents" on the cover page is deleted.

         (d) The definition of Agents in Section 1.01 is amended to read as
follows:

         "AGENTS" means the Administrative Agent and the Syndication Agents.

         (e) The definition of Documentation Agents in Section 1.01 is deleted.

         (f) The definition of Senior Managing Agents in Section 1.01 is
deleted.



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<PAGE>

         (g) The definition of Syndication Agents in Section 1.01 is amended to
read as follows:

         "SYNDICATION AGENTS" means, Bank of America, N.A., The Bank of
Tokyo-Mitsubishi, Ltd., Citicorp USA, Inc. and Credit Suisse First Boston, in
their capacities as syndication agents in connection with the credit facility
provided under this Agreement.

         (h) Section 7.10 is amended to read in its entirety as follows:

         Section 7.10. Other Agents. Nothing in this Agreement shall impose any
duty or liability whatsoever on any Syndication Agent in such capacity.

         Section 8 . Representations And Warranties. The Borrower hereby
represents and warrants that as of the date hereof and after giving effect
hereto:

         (a) no Default has occurred and is continuing; and

         (b) each representation and warranty of the Borrower set forth in the
Agreement after giving effect to this Amendment and Restatement is true and
correct as though made on and as of such date.

         Section 9 . Governing Law. This Amendment and Restatement shall be
governed by and construed in accordance with the laws of the State of New York.

         Section 10 . Counterparts; Effectiveness. This Amendment and
Restatement may be signed in any number of counterparts, each of which shall be
an original, with the same effect as if the signatures thereto and hereto were
upon the same instrument. This Amendment and Restatement shall become effective
as of August 22, 2001 when each of the following conditions shall have been
satisfied:

                  (i)   receipt by the Administrative Agent of duly executed
         counterparts hereof signed by each of the parties hereto (or, in the
         case of any party as to which an executed counterpart shall not have
         been received, the Administrative Agent shall have received
         telegraphic, telex or other written confirmation from such party of
         execution of a counterpart hereof by such party);

                  (ii)  receipt by the Administrative Agent of a duly executed
         Note for each of the New Banks (a "NEW NOTE"), dated on or before the
         date of effectiveness hereof and otherwise in compliance with Section
         2.06 of the Agreement;

                  (iii) receipt by the Administrative Agent of an opinion of
         counsel for the Borrower satisfactory to the Administrative Agent,
         substantially to the effect of Exhibits E-1 and E-2 to the Agreement
         with



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<PAGE>


         reference to this Amendment and Restatement and the Agreement as
         amended and restated hereby; and

                  (iv)  receipt by the Administrative Agent of all documents it
         may reasonably request relating to the existence of the Borrower, the
         corporate authority for and the validity of the Agreement as amended
         and restated hereby, and any other matters relevant hereto, all in form
         and substance satisfactory to the Administrative Agent;

provided that this Amendment and Restatement shall not become effective or
binding on any party hereto unless all of the foregoing conditions are satisfied
not later than the date hereof. The Administrative Agent shall promptly notify
the Borrower and the Banks of the effectiveness of this Amendment and
Restatement, and such notice shall be conclusive and binding on all parties
hereto.


                                       4



<PAGE>


         IN WITNESS WHEREOF, the parties hereto have caused this Amendment and
Restatement to be duly executed by their respective authorized officers as of
the day and year first above written.

                        BORROWER:
                        ---------
                                              GUIDANT CORPORATION

                                              By: /s/ R. Todd McKinney
                                                  -----------------------------
                                              Title: Treasurer




                        ADMINISTRATIVE AGENT:
                        --------------------


                                              MORGAN GUARANTY TRUST
                                                COMPANY OF NEW YORK, as
                                                Administrative Agent


                                              By: /s/ Robert Bottamedi
                                                  -----------------------------
                                              Title: Vice President




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<PAGE>


                        BANKS:
                        ------

                                              THE CHASE MANHATTAN BANK


                                              By: /s/ Robert Bottamedi
                                                  -----------------------------
                                              Title: Vice President



                                              MORGAN GUARANTY TRUST
                                                COMPANY OF NEW YORK


                                              By: /s/ Robert Bottamedi
                                                  -----------------------------
                                              Title: Vice President



                                              BANK OF AMERICA, N.A.


                                              By: /s/ Larry J. Gordon
                                                  -----------------------------
                                              Title: Principal



                                              THE BANK OF TOKYO-
                                                MITSUBISHI,  LTD.


                                              By: /s/ Hisashi Miyashiro
                                                  -----------------------------
                                              Title: Deputy General Manager




                                              CITICORP USA, INC.


                                              By: /s/ Emily Rosenstock
                                                  -----------------------------
                                              Title: Managing Director


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<PAGE>


                                              CREDIT SUISSE FIRST BOSTON

                                              By: /s/ William S. Lutkins
                                                  -----------------------------
                                              Title: Vice President


                                              By: /s/ Robert N. Finney
                                                  -----------------------------
                                              Title: Managing Director



                                              BNP PARIBAS


                                              By: /s/ Richard L. Sted
                                                  -----------------------------
                                              Title: Central Region Manager


                                              By: /s/ Jo Ellen Bender
                                                  -----------------------------
                                              Title: Director


                                              DEUTSCHE BANK AG,
                                                NEW YORK BRANCH AND/OR
                                                CAYMAN ISLANDS BRANCH


                                              By: /s/ Ian Stewart
                                                  -----------------------------
                                              Title: Director


                                              By: /s/ Stephanie Strohe
                                                  -----------------------------
                                              Title: Vice President


                                              ING (US) CAPITAL LLC


                                              By: /s/ Peter Vissers
                                                  -----------------------------
                                              Title: Director

                                       7



<PAGE>


                                              ABN AMRO BANK N.V.


                                              By: /s/ Gina M. Brusatori
                                                  -----------------------------
                                              Title: Senior Vice President


                                              By: /s/ Alex Miller
                                                  -----------------------------
                                              Title: Vice President


                                              SOCIETE GENERALE


                                              By: /s/ G. Wayne Hosang
                                                  -----------------------------
                                              Title: Vice President


                                              THE NORTHERN TRUST COMPANY


                                              By: /s/ Nicole D. Boehm
                                                  -----------------------------
                                              Title: Second Vice President


                                              SUNTRUST BANK


                                              By: /s/ W. Brook Hubbard
                                                  -----------------------------
                                              Title: Vice President


                                              THE GOVERNOR AND
                                                COMPANY OF THE BANK OF
                                                IRELAND


                                              By: /s/ Dara Moloney
                                                  -----------------------------
                                              Title: Senior Account Executive


                                              By: /s/ Fergus McDonald
                                                  -----------------------------
                                              Title: Associate Director



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<PAGE>


                                              BANCA MONTE DEI PASCHI DI
                                                SIENA S.P.A.


                                              By: /s/ Giulio Natalicchi
                                                  -----------------------------
                                              Title: Senior Vice President &
                                                     General Manager


                                              By: /s/ Brian R. Landy
                                                  -----------------------------
                                              Title: Vice President


                                              BANK ONE, INDIANA, NA


                                              By: /s/ James A. Tutt, Jr.
                                                  -----------------------------
                                              Title: First Vice President


                                              WACHOVIA BANK N.A.


                                              By: /s/ Elizabeth M. Phelan
                                                  -----------------------------
                                              Title: Vice President



                                              NATIONAL CITY BANK OF INDIANA


                                              By: /s/ Tracy J. Venable
                                                  -----------------------------
                                              Title: Vice President

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<PAGE>
                               COMMITMENT SCHEDULE
                             364-DAY CREDIT FACILITY



BANK                                                      COMMITMENT
-------------------------------------------------------   -----------------
The Chase Manhattan Bank                                  $      70,000,000

Bank of America, N.A.                                     $      45,000,000

The Bank of Tokyo-Mitsubishi, Ltd.                        $      45,000,000

Citicorp USA, Inc.                                        $      45,000,000

Credit Suisse First Boston                                $      45,000,000

BNP Paribas                                               $      40,000,000

Deutsche Bank AG, New York Branch and/or
Cayman Islands Branch                                     $      40,000,000

ING (US) Capital LLC                                      $      40,000,000

ABN AMRO Bank N.V.                                        $      40,000,000

Societe Generale                                          $      35,000,000

The Northern Trust Company                                $      30,000,000

SunTrust Bank                                             $      25,000,000

The Governor and Company of the Bank of Ireland           $      25,000,000

Banca Monte dei Paschi di Siena S.p.A                     $      25,000,000

Morgan Guaranty Trust Company of New York                 $               0

Bank One, Indiana, NA                                     $               0

Wachovia Bank N.A.                                        $               0

National City Bank of Indiana                             $               0
                                                          -----------------
                  TOTAL                                   $  550,000,000.00



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