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                                                                   EXHIBIT 10.31


                           NEGATIVE PLEDGE AGREEMENT

  This Negative Pledge Agreement is made as of August 1, 2001 by and between
NOVOSTE CORPORATION ("Borrower") and Silicon Valley Bank ("Bank").

In connection with, among other documents, the Loan and Security Agreement (the
"Loan Documents") being concurrently executed herewith between Borrower and
Bank, Borrower agrees as follows:

     1.   Except for non-exclusive licenses granted in the ordinary course of
          business, Borrower shall not sell, transfer, assign, mortgage, pledge,
          lease, grant a security interest in, or encumber any of Borrower's
          intellectual property, including, without limitation, the following:

          a.   Any and all copyright rights, copyright applications, copyright
               registrations and like protections in each work or authorship and
               derivative work thereof, whether published or unpublished and
               whether or not the same also constitutes a trade secret, now or
               hereafter existing, created, acquired or held;

          b.   All mask works or similar rights available for the protection of
               semiconductor chips, now owned or hereafter acquired;

          c.   Any and all trade secrets, and any and all intellectual property
               rights in computer software and computer software products now or
               hereafter existing, created, acquired or held;

          d.   Any and all design rights which may be available to Borrower now
               or hereafter existing, created, acquired or held;

          e.   All patents, patent applications and like protections including,
               without limitation, improvements, divisions, continuations,
               renewals, reissues, extensions and continuations-in-part of the
               same, including without limitation the patents and patent
               applications;

          f.   Any trademark and servicemark rights, whether registered or not,
               applications to register and registrations of the same and like
               protections, and the entire goodwill of the business of Borrower
               connected with and symbolized by such trademarks, including
               without limitation;

          g.   Any and all claims for damages by way of past, present and future
               infringements of any of the rights included above, with the
               right, but not the obligation, to sue for and collect such
               damages for said use or infringement of the intellectual property
               rights identified above;

          h.   All licenses or other rights to use any of the Copyrights,
               Patents, Trademarks or Mask Works, and all license fees and
               royalties arising from such use to the extent permitted by such
               license or rights; and

          i.   All amendments, extensions, renewals and extensions of any of the
               Copyrights, Trademarks, Patents, or Mask Works; and

          j.   All proceeds and products of the foregoing, including without
               limitation all payments under insurance or any indemnity or
               warranty payable in respect of any of the foregoing;

     2.   It shall be an event of default under the Loan Documents between
          Borrower and Bank if there is a breach of any term of this Negative
          Pledge Agreement.