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                                 EXHIBIT 10.18
                   AMENDMENT 2 TO LICENSE AGREEMENT BETWEEN
                       INTERMEDICS INC.  AND THE COMPANY
                            DATED OCTOBER 20, 1995







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                       AMENDMENT 2 TO LICENSE AGREEMENT

        This Amendment is entered into as of October 20, 1995, by and between 
Intermedics Inc. ("ITM"), a Delaware corporation, and Cardiac Control Systems, 
Inc. ("CCS"), having a principal place of business at 3 Commerce Boulevard, Palm
Coast, Florida 32164.

        WHEREAS ITM and CCS are parties to an amended and restated license 
agreement dated April 2, 1993 (the "License Agreement") and

        WHEREAS ITM and CCS are also parties to an amended and restated supply
contract also dated April 2, 1993 (the "Supply Contract") and

        WHEREAS, under the terms of a promissory note and security agreement of 
even date herewith (the "Note"), ITM has agreed to loan CCS $1.0 million to 
assist CCS in its refinancing efforts and

        WHEREAS CCS will repay the loan by way of certain withholdings from the 
price Intermedics pays for packaged leads under the Supply Contract or, under 
certain circumstances specified in the Note, by a reduction of Intermedics' 
royalty payments under the License Agreement and

        WHEREAS the parties now desire to amend the License Agreement to conform
it to certain provisions of the Note and to clarify the intention of the
parties,

        THEREFORE, in consideration of the mutual promises set forth in this 
Amendment and other good and valuable consideration, the parties agree:

        1.  A new paragraph is added to the end of section 4.1 of the License
Agreement which reads:

             Notwithstanding the foregoing, if for any reason CCS cannot or will
        not supply leads to ITM under the Supply Contract to satisfy CCS's
        obligations under the promissory note and security agreement dated
        October 20, 1995, then ITM will reduce the royalty payments it owes
        under the License Agreement by $250 per lead for the first 4,000 leads
        sold after such failure or refusal to supply and by $90 per lead
        thereafter. Such withholding will continue only until CCS satisfies its
        obligations under the promissory note and security agreement.
        
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        2.  By way of clarification, a new clause is added to the end of the 
first sentence of section 2.5 which reads:

        . . . ; provided further that the right reserved to CCS in the preceding
        clause does not include the right to sublicense the Licensed Technology
        or the Licensed Patents or to supply Licensed Products (including
        without limitation packaged Leads, partially assembled Leads or Lead
        components) to a current competitor of ITM as that term is defined in
        section 4.3 hereof.

        Unless expressly modified by this Amendment, all other provisions in the
License Agreement will remain unchanged and in full force and effect.

Cardiac Control Systems, Inc.                   Intermedics Inc.


by: /s/ Alan J. Rabin                           by: /s/ John E. Garcia
    ------------------------                        -------------------------
    Alan J. Rabin, President                        John E. Garcia, President



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