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                                                               EXHIBIT 10.12

                           PROMISSORY NOTE

$200,000.00                                              January 31, 1997

     1.     PRINCIPAL AND INTEREST. FOR VALUE RECEIVED, the 
undersigned borrower ("Borrower") promises to pay to Perclose, Inc., a 
Delaware corporation (the "Company"), or order, at its principal offices 
the principal amount of $200,000.00 with interest thereon on the rate of five 
and 81/100 percent (5.81%) per annum, compounded annually from the date 
hereof, on the unpaid balance of the principal sum. Principal and interest 
shall be due and payable on December 31, 1999.

     Interest accruing on the principal amount of the Note from the date 
hereof until December 31, 1999 shall be added to the principal amount of the 
Note. Payments, if any, received between the date hereof and December 31, 
1999 shall be considered to be repayments of the principal amount of the Note.

     2.     REPAYMENT. Notwithstanding the foregoing, in the event that the 
Borrower's employment with the Company is terminated for any reason prior to 
repayment of the principal of and accrued interest on this Note, all such 
outstanding principal and accrued interest shall be due and payable upon the 
termination of the Borrower's employment.

     In the event of a merger of the Company with or into another corporation 
or the sale of substantially all of the assets of the Company, the Note may 
be assigned to the successor corporation or a Parent or Subsidiary thereof 
(the "Successor Corporation"). If the Note is assigned, the Borrower shall 
continue to repay the Note as provided above to the Successor Corporation. 
Following such an assignment, in the event that the Borrower's employment 
with the Successor Corporation is terminated for any reason prior to 
repayment of the principal of and accrued interest on this Note, all such 
outstanding principal and accrued interest shall be due and payable upon the 
termination of the Borrower's employment.

     All principal and interest is payable in lawful money of the United 
States of America. THE PRIVILEGE IS RESERVED TO PREPAY ANY PORTION OF THE 
NOTE AT ANY TIME WITHOUT PENALTY.

     3.     SECURITY. This Note is secured by a pledge of options to acquire 
10,000 shares of Common Stock of the Company and all shares of Common Stock 
issuable upon exercise of such options (collectively, the "Pledged 
Securities") held by Borrower. The parties agree that the options to acquire 
the Common Stock of the Company which are included among the Pledged 
Securities shall be the first options to become vested in the Borrower. The 
Borrower shall deliver to the Secretary of the Company as escrow agent 
("Escrow Holder") all certificates or instruments representing the Pledged 
Securities. In the event of default in payment when due of any indebtedness 
under the Note, the Company may elect then, or at any time thereafter, to 
exercise all rights available to a secured party under the California Uniform 
Commercial Code, including the right to sell the Pledged Securities at a 
private or public sale or repurchase the Pledged Securities. The parties 
agree that the repurchasing of the Pledged Securities by the Company, or by 
any person to whom the Company may 

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have assigned its rights hereunder, is commercially reasonable if made at the 
Fair Market Value (as defined below) of the Pledged Securities. "Fair Market 
Value" means, as of any date, the value of Common Stock determined as follows:

     (a)  If the Pledged Securities are listed on any established stock 
          exchange or a national market system, including without limitation 
          the Nasdaq National Market or The Nasdaq SmallCap Market of The 
          Nasdaq Stock Market, their Fair Market Value shall be the closing 
          sales price for such securities (or the closing bid, if no sales 
          were reported) as quoted on such exchange or system for the last 
          market trading day prior to the time of determination, as reported 
          in THE WALL STREET JOURNAL;

     (b)  If the Pledged Securities are regularly quoted by a recognized 
          securities dealer but selling prices are not reported, the Fair 
          Market Value of a such securities shall be the mean between the high 
          bid and low asked prices for such securities on the date of 
          determination, as reported in THE WALL STREET JOURNAL; or

     (c)  In the absence of an established market for the Pledged Securities, 
          the Fair Market Value thereof shall be determined in good faith by 
          the Board of Directors of the Company.

     The proceeds of any sale or repurchase shall be applied in the following 
order:

     1.   To pay all reasonable expenses of the Company in enforcing this 
          Note, including reasonable attorney's fees.

     2.  In satisfaction of the remaining indebtedness under the Note.

     3.  To the Borrower, any remaining proceeds.

     Upon full payment by the Borrower of all amounts due on the Note, the 
Escrow Holder shall deliver to the Borrower the instrument(s) or 
certificate(s) representing the Pledged Securities in the Escrow Holder's 
possession belonging to the Borrower and the executed original of the Note 
marked "canceled" by the Company, and the Escrow Holder shall be discharged 
of all further obligations hereunder.

     Except for the above-referenced pledge, none of the Pledged Securities 
or any beneficial interest therein shall be transferred, encumbered or 
otherwise disposed of in any way until the payment in full of the Note, other 
than by will or the laws of descent and distribution; provided, however, that 
the Company may, upon request of the Borrower but at the sole discretion of 
the Company, consent to the release from escrow of some or all of the Pledged 
Securities to the Borrower for the purpose of allowing the Borrower to 
exercise some or all of the vested options which are Pledged Securities (the 
"Released Options") and to sell the shares of Common Stock issued 


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upon exercise of the Released Options for the purpose of repaying any part 
of the principal amount of this Note and/or any part of the accrued interest 
thereon.

     The Borrower agrees to execute such instruments and other documents and 
to take such other actions as the Company shall request for the purpose of 
carrying out the purposes of this Section 3.

     4. MISCELLANEOUS. Should any action or proceeding be commenced to 
collect this Note or any portion of this Note, such sum as the court may deem 
reasonable shall be added hereto as attorneys' fees. The Borrower waives 
presentment for payment, protest, notice of protest, and notice of nonpayment 
of this Note. This Note shall be governed by and construed according to the 
laws of the State of California, without regard to the conflicts of law 
provisions thereof.

                                           /s/ John G. McCutcheon
                                          ------------------------------
                                          (Signature of Borrower)

                                          John G. McCutcheon
                                          ------------------------------
                                          (Print Name of Borrower)

     Agreed to and accepted as of the date set forth above:

PERCLOSE, INC.

By: /s/  Kenneth E. Ludlum
   ----------------------------

Name: Kenneth E. Ludlum
     --------------------------

Title: Vice President, Finance
       and Administration
      -------------------------

Date: January 31, 1997
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