EXHIBIT 10.90


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                        RESTATED DEBT REPAYMENT AGREEMENT

     This  Agreement (the  "Agreement")  is made effective as of the 15th day of
May, 1997, by and between Sparta Surgical  Corporation,  a Delaware corporation,
having its principal offices at 7068 Koll Center Parkway, Bernal Corporate Park,
Suite 401, Pleasanton,  California 94566 (the "Company"),  and Thomas F. Reiner,
President,  Chief  Executive  Officer  and  Chairman of the Board of the Company
("Reiner").

     WHEREAS,  Reiner was, on the date of a Debt Repayment Agreement  previously
entered  into  between  the  Company and  himself  (the  "Original  Agreement"),
indebted  to the  Company  in the  amount of  approximately  $556,413.00,  which
consisted  of the  amount of  approximately  $210,000.00  owing  from him to the
Company  pursuant  to a  non-interest  bearing  promissory  note,  the amount of
$222,419.00 owing from him to the Company pursuant to a promissory note, bearing
interest at the rate of six percent (6%) per annum (the "Interest Bearing Note")
and the amount of approximately  $123,994.00  owing as an account  receivable of
the  Company,  as the amounts  owing on such  obligations  may be  increased  or
decreased from time to time (the "Debt");

     WHEREAS,  the  Company  and  Reiner are  desireous  of  entering  into this
Agreement in place of and in lieu of the Original  Agreement,  with the Original
Agreement being hereafter null and void and of no effect; and

     WHEREAS,  Reiner has offered to repay the Debt in the manner  provided  for
herein out of his future salary and has agreed to permit the Company to pay such
amounts  directly  in the manner  provided  herein and the Company has agreed to
such arrangement;

     NOW,  THEREFORE,  in  consideration  of the mutual covenants and agreements
hereinafter  set  forth,  and for other  good and  valuable  consideration,  the
receipt and sufficiency of which are hereby acknowledged, the Company and Reiner
agree as follows:

     1. Repayment.  Reiner agrees to repay the Debt by paying to the Company the
following  amounts of his annual  base salary (as such term is used in Section 4
(a) of Reiner's  Employment  Agreement with the Company dated April 8, 1996 (the
"Employment  Agreement"))  during  each  year  of the  term  of  his  Employment
Agreement:

Period                              Annual Payment Amount

5/15/1997 - 4/7/1998                $50,000.00 (less amounts previously paid)
4/8/1998 - 4/7/1999                 $50,000.00
4/8/1999 - 4/7/2000                 $55,000.00
4/8/2000 - 4/7/2001                 $60,000.00
4/8/2001 - 4/7/2002                 $60,000.00
4/8/2002 - 4/7/2003                 $65,000.00
4/8/2003 - 4/7/2004                 $70,000.00
4/8/2004 - 4/7/2005                 $70,000.00
4/8/2005 - 4/7/2006                 Balance outstanding on 4/8/2005


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     Such annual amounts (each being a "Debt Reduction Payment") shall be repaid
by Riener in twelve equal  installments  payable on the first date of each month
(commencing  July 1, 1997) during the year to which such Debt Reduction  Payment
pertains.  In the event that the entire  amount of the Debt is satisfied for any
reason  (including  in the  event  of the  termination  of  Reiner's  employment
pursuant to Section 4 (g) of the Employment  Agreement) Reiner shall be entitled
to receive any amounts owing to him under the Employment  Agreement  without the
Debt Reduction Payments being deducted, offset or otherwise deemed owing.

     2. Modification of Certain Terms of the Debt;  Application of Payments.  In
consideration of Reiner's entering into this Agreement,  the Company agrees that
(i) the due date for each  portion  of the Debt  shall be  extended  to April 7,
2006;  (ii) all interest owing under the Interest  Bearing Note shall be waived;
and (iii) the terms of the  Interest  Bearing Note shall be modified so that the
Interest  Bearing  Note no longer  requires  the  payment of any  interest.  All
payments  made  pursuant to this  Agreement  shall be applied  first to interest
owing on the Debt and to such  portion  of the  Debt  which  represents  accrued
interest owing from Reiner to the Company (together  representing  approximately
$319,209 in accrued interest) and thereafter to principal.

     3.  Payment of Tax  Liability.  The  Company  agrees to pay to Reiner  each
month,  as additional  compensation,  the  estimated  amount of (i) any federal,
state and local  income or excise  taxes that  Reiner must pay for such month on
his salary  with  respect to amounts  being  repaid to the  Company as a monthly
installment  against the Debt  Reduction  Payment,  as a result of any waiver of
interest on the  Interest  Bearing  Note and as to any  imputed  interest on the
Interest  Bearing  Note  hereafter;  and (ii) an  additional  sum of  money,  as
compensation  for any federal,  state and local  income or excise taxes  payable
upon  payments  made  pursuant to this Section 3,  including any such taxes upon
payments  pursuant to this  subsection  (ii), the intention  being that payments
pursuant  to this  subsection  (ii) shall  equal such  amount as is  required to
entirely  repay  any cost to  Reiner  for such  taxes.  Payment  of any  amounts
pursuant to this Section 3 shall be calculated at the highest  marginal tax rate
as to which  Reiner  might be subject  for the tax year in which the income from
the  forgiveness  of such  of the  Indebtedness  is  recognized,  regardless  of
Reiner's actual marginal rates.

     4. Notice:  Any notices  required to be given pursuant to the provisions of
this  Agreement  shall be in writing and  delivered  by hand  delivery,  express
delivery service or by certified mail return receipt requested to the parties at
the following addresses:

                  Company: Sparta Surgical Corporation
                           7068 Koll Center Parkway
                           Bernal Corporate Park, Suite 401
                           Pleasanton, California 94566

                  Reiner:  Thomas F. Reiner
                           4478 Fleetwood Road
                           Danville, California  94506


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     5. Successors; Binding Effect.

          (a) The  Company  shall  require  any  successor  (whether  direct  or
indirect  by  purchase  of  assets,  purchase  or  exchange  of  stock,  merger,
consolidation or otherwise) to all or  substantially  all of the business and/or
assets of the  Company,  by  agreement  in form and  substance  satisfactory  to
Reiner,  to  expressly  assume and agree to perform  this  Agreement in the same
manner and to the same extent  that the Company  would be required to perform it
if no such  succession  had taken  place.  Failure of the Company to obtain such
agreement prior to the effectiveness of any such succession shall be a breach of
this Agreement and shall result in the total forgiveness of the Debt. As used in
this  Agreement,  "Company"  shall  mean  Sparta  Surgical  Corporation  and any
successor to the business  and/or assets of Sparta  Surgical  Corporation  which
executes and delivers the agreement  provided for in this Section 5 (a) or which
otherwise  becomes bound by all of the terms and provisions of this Agreement by
operation of law.

          (b) This Agreement and all rights of Reiner  hereunder  shall inure to
the benefit of and be  enforceable  by the  administrators,  successors,  heirs,
distributees, devisees and legatees of Reiner.

     6.  Arbitration.  At the election of Reiner,  any dispute  respecting  this
Agreement,  whether  commenced  by the  Company  or Reiner  may be  resolved  by
arbitration before a three person panel of independent  arbitrators  pursuant to
the  Commercial  Rules of the  American  Arbitration  Association  ("AAA").  Any
arbitration  compelled  pursuant to this section shall be held at the AAA office
nearest to Reiner's residence at the time such action is commenced. Reiner shall
be entitled to a stay of any legal proceeding  instituted against by the Company
in the event that an election to arbitrate pursuant to this Section is made.

     7.  Attorney's  Fees  and  Litigation.  In any  litigation  or  arbitration
relating to this Agreement the Company shall bear all costs and attorney's  fees
of both parties.

     8. Authority. Each party represents that its undersigned  representative or
corporate  officer  has all  requisite  power and  authority  to enter into this
agreement  and to execute any and all  instruments  and  documents on its behalf
necessary to and in performance of their respective obligations hereunder.

     9.   Counterparts.   This   Agreement  may  be  executed  in  one  or  more
counterparts,  each of which shall be deemed original, but all of which together
shall constitute one and the same instrument.

     10.  Severability.  If any provisions of this Agreement shall be held to be
invalid or unenforceable to any extent or in any application, then the remainder
of this Agreement and such term and condition,  except to such extent or in such
application,  shall  not be  affected  thereby,  and  each  and  every  term and
condition of this  Agreement  shall be valid and enforced to the fullest  extent
and in the broadest application permitted by law.


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     11. Headings:  The paragraph  headings contained herein are for convenience
and reference  only, and shall be given no effect in the  interpretation  of any
term or condition of this Agreement.

     12.  Miscellaneous.  This  Agreement is entered into and shall be construed
under the laws of the State of California applicable to contracts made and to be
entirely performed which that State. In the event that,  notwithstanding Section
6 hereof,  any litigation  relating to this Agreement is held to be permissible,
the venue thereof shall be in the appropriate  court with  jurisdiction over the
matter in  dispute  for the  county in which  Reiner  resides at the time of the
filing of the lawsuit in question. This Agreement shall be amended,  modified or
terminated  only by an instrument in writing,  signed by the party or parties to
be charged.  This Agreement shall inure to the benefits of the parties and their
successors in interest.  This  Agreement is the entire  agreement of the parties
relating to the  employment of Reiner by the Company and supersedes all previous
written or oral agreements.

     IN WITNESS  WHEREOF the parties have executed this Agreement under seal the
day and year first above written.

                                                SPARTA SURGICAL CORPORATION
                                                By its Board of Directors with
                                                Reiner abstaining



      /s/ Alan J.  Korn                           /s/ Michael Y.  Granger
     Alan J. Korn, Director                     Michael Y. Granger, Director

                                                REINER:


                                                   /s/ Thomas F.  Reiner
                                                 Thomas F. Reiner, Individually


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