Magna-Lab Inc.

P.O. Box 780
Syosset, NY 11791
(516) 393 5874
Writers Direct Dial: (516) 869 8265
Writers Mobile Phone: (516) 241 8523

April 14, 2000

Ms. Sharon Mias
Administrator,
Cardiovascular Institute, Mount Sinai Medical Center
One Gustave Levy Plaza
New York, NY 10029-6574

Dear Ms. Mias:

The purpose of this letter is to confirm the conclusions  that have been reached
in meetings and discussions with the leadership of the Cardiovascular  Institute
since our meeting  transpired  on January 9, 2000.  The January 9, 2000  meeting
resulted in the January 24, 2000  agreement to amend the payment terms  relative
to our May 1997 Collaborative  Research Agreement with The Mount Sinai School of
Medicine (the  "Agreement") to more clearly reflect the status of the work under
the Agreement (copy enclosed).

It is now the desire of the parties that the payment terms of Section 2.4 of the
Agreement  which were  modified in the January  24,  2000  letter  amendment  be
revised to reflect the following, again to more appropriately reflect the status
of the work efforts as follows:

     $150,000 payment in March 2000 (already paid)
     $150,000 payment in April 2000 (enclosed herewith)
     $150,000 at the end of July and again at the end of October 2000.

This  schedule will result in the total  payments of  $1,500,000  being made and
will  reflect  actual  differences  in the  scheduling  of  the  work  vs.  that
scheduling contemplated by the Agreement.

If this  correctly  reflects  our  discussion,  would you kindly  indicate  your
agreement below. Thank you.

Sincerely,
Magna-Lab Inc.



/s/Lawrence A. Minkoff
Lawrence A. Minkoff, Ph.D., President


Agreed:
Mount Sinai School of Medicine


/s/Sharon Mias
--------------
Sharon Mias, Administrator