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                                                                   EXHIBIT 10.50



                            NONCOMPETITION AGREEMENT


        THIS NONCOMPETITION AGREEMENT is made and entered into this 15th day of
August 1997, by and between David E. Wertheimer, an individual ("Stockholder"),
and Raytel Medical Corporation, a Delaware corporation ("Raytel"). For the
purposes of this Agreement, "Raytel" shall be deemed to include Raytel and its
majority owned direct and indirect subsidiaries during the term of this
Agreement.

                                           Recitals

        A. Cardiovascular Ventures, Inc., a Delaware corporation ("CVI"),
directly and through its subsidiaries, is engaged in the business of developing
and managing cardiac catheterization facilities and the management of a
professional physician association that operates a multi-speciality clinic (the
"Business of CVI");

        B. Pursuant to that certain Stock Purchase Agreement (the "Stock
Purchase Agreement") as of dated August 11, 1997 by and among Raytel, CVI and
the Stockholders of CVI, Raytel is acquiring CVI through the purchase of all
outstanding shares of the capital stock of CVI (the "Acquisition") pursuant to
which CVI will continue to operate the Business of CVI as a wholly-owned
subsidiary of Raytel;

        C. Stockholder is the beneficial owner of shares of capital stock of CVI
and is an officer or a key employee of CVI;

        D. Stockholder has been actively involved in the management of CVI; and

        E. In consideration of and as an inducement to Raytel to consummate the
Acquisition, Stockholder, intending to be bound hereby, has agreed to execute
this Agreement.

        NOW, THEREFORE, the parties agree as follows:

        1. Covenant Not to Compete.

           (a) Stockholder agrees that, except as otherwise set forth in
paragraph (b) below, for so long as he is employed by or serves as a consultant
to Raytel and for a period of two (2) years thereafter (the "Noncompetition
Period"), he will not, directly or indirectly, individually or as an owner,
partner, stockholder, joint venturer, corporate officer, director, employee,
consultant, principal, agent, trustee or licensor, or in any other similar
capacity whatsoever of or for any person, firm, partnership, company or
corporation (other than Raytel), solicit, request or advise any of the
customers, prospective customers, suppliers or other business contacts of CVI or
Raytel, or any subsidiary or joint venture of CVI or Raytel, with which
Stockholder had contact or of which he had knowledge while employed by CVI or
Raytel to withdraw, curtail, cancel or not increase their business with CVI or
Raytel. Stockholder agrees to notify Raytel of each employment or consulting
position he accepts during the Noncompetition Period (including 




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the name and address of the hiring party) and will, upon request by Raytel,
describe in reasonable detail the nature of his duties in each such position.

           (b) Notwithstanding the provisions of paragraph (a) above, the
Noncompetition Period will terminate upon the date one (1) year after any
transaction or series of transactions pursuant to which any person (or group of
persons) other than the current affiliates of Raytel acquires more than fifty
percent (50%) of the outstanding shares of Raytel's voting securities, whether
pursuant to a tender offer, exchange offer, merger or otherwise.

        2. Nonsolicitation of Employees and Consultants. During the
Noncompetition Period, Stockholder agrees that he will not directly or
indirectly solicit, influence, entice or encourage any person who at such time
is, or who at any time in the three (3) month period prior to such time had
been, an employee of or consultant to Raytel or CVI, or any subsidiary of CVI,
to cease or curtail his or her relationship therewith.

        3. Nondisruption; Other Matters. During the Noncompetition Period,
Stockholder agrees that he will not directly or indirectly interfere with,
disrupt or attempt to disrupt any past, present or prospective relationship,
contractual or otherwise, between Raytel or CVI, on the one hand, and any of
their respective customers, suppliers or employees, on the other hand.

        4. Equitable Relief. Stockholder acknowledges and agrees that Raytel's
remedies at law for breach of any of the provisions of this Agreement would be
inadequate and, in recognition of this fact, Stockholder agrees that, in the
event of such breach, in addition to any remedies at law it may have, Raytel,
without posting any bond, shall be entitled to obtain equitable relief in the
form of specific performance, a temporary restraining order, a temporary or
permanent injunction or any other equitable remedy that may be available.
Stockholder further acknowledges that should Stockholder violate any of the
provisions of this Agreement, it will be difficult to determine the amount of
damages resulting to Raytel and that in addition to any other remedies it may
have, Raytel shall be entitled to temporary and permanent injunctive relief
without the necessity of proving damages.

        5. Acknowledgment. Each of Stockholder and Raytel acknowledges and
agrees that the covenants and agreements contained in this Agreement have been
negotiated in good faith by the parties, are reasonable and are not more
restrictive or broader than necessary to protect the interests of the parties
thereto, and would not achieve their intended purpose if they were on different
terms or for periods of time shorter than the periods of time provided herein or
applied in more restrictive geographical areas than are provided herein. Each
party further acknowledges that Raytel would not enter into the Stock Purchase
Agreement and the transactions contemplated thereby in the absence of the
covenants and agreements contained in this Agreement and that such covenants and
agreements are essential to protect the value of CVI to Raytel.

        6. Separate Covenants. The covenants contained in this Agreement shall
be construed as a series of separate covenants, one for each of the counties in
each of the states of the United States of America.




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        7. Severability. The parties agree that construction of this Agreement
shall be in favor of its reasonable nature, legality and enforceability, and
that any construction causing unenforceability shall yield to a construction
permitting enforceability. It is agreed that the noncompetition and
nonsolicitation covenants and provisions of this Agreement are severable, and
that if any single covenant or provision or multiple covenants or provisions
should be found unenforceable, the entire Agreement and remaining covenants and
provisions shall not fail but shall be construed as enforceable without any
severed covenant or provision in accordance with the tenor of this Agreement.
The parties specifically agree that no covenant or provision of this Agreement
shall be invalidated because of overbreadth insofar as the parties acknowledge
the scope of the covenants and provisions contained herein to be reasonable and
necessary for the protection of Raytel and CVI and not unduly restrictive upon
Stockholder. However, should a court or any other trier of fact or law determine
not to enforce any covenant or provision of this Agreement as written due to
overbreadth, then the parties agree that said covenant or provision shall be
enforced to the extent reasonable, with the court or such trier to make any
necessary revisions to said covenant or provision to permit its enforceability.

        8. Not an Employment Agreement. This Agreement is not, and nothing in
this Agreement shall be construed as, an agreement to provide employment to
Stockholder. The provisions of Paragraphs 1, 2, and 3 of this Agreement shall be
operative regardless of the reasons for any termination of Stockholder's
employment and regardless of the performance or nonperformance by any party
under any other section of this Agreement.

        9. Governing Law. This Agreement is made under and shall be governed by,
construed in accordance with and enforced under the internal laws of the State
of Delaware. All disputes arising under this Agreement shall be brought in the
federal and state courts located in Santa Clara County, California, as permitted
by law, and each of the parties hereby consents to the personal jurisdiction,
service of process and venue of such courts.

        10. Entire Agreement. This Agreement, together with the Stock Purchase
Agreement, constitutes and contains the entire agreement and understanding
concerning the subject matter addressed herein between the parties, and
supersedes and replaces all prior negotiations and all agreements proposed or
otherwise, whether written or oral, concerning the subject matter hereof, and
the parties hereto have made no agreements, representations or warranties
relating to the subject matter of this Agreement that are not set forth herein
or in the Stock Purchase Agreement.

        11. Notices. Any notice or other communication under this Agreement
shall be in writing, signed by the party making the same, and shall be delivered
personally or sent by certified or registered mail, postage prepaid, addressed
as follows:

           If to Stockholder: David E. Wertheimer
           2443 S.W. Brookwood Lane
           Palm City, FL 34990
           Facsimile:_______________




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           If to Raytel:      Raytel Medical Corporation
                              2755 Campus Drive, Suite 200
                              San Mateo, CA 94403-2515
                              Facsimile: (650) 349-8850
                              Attn:  President

        with a copy to:       Gray Cary Ware & Freidenrich
                              400 Hamilton Avenue
                              Palo Alto, CA  94301
                              Facsimile: (650) 327-3699
                              Attn: Dennis C. Sullivan

or to such other address as may hereafter be designated by either party hereto.
All such notices shall be deemed given on the date personally delivered or
mailed.

        12. Waiver of Jury Trial. EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY
WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF
OR RELATED TO THIS AGREEMENT.

        13. Amendments; No Waiver.

           (a) No amendment or modification of this Agreement shall be deemed
effective unless made in writing and signed by the parties hereto.

           (b) No term or condition of this Agreement shall be deemed to have
been waived, nor shall there be any estoppel to enforce any provision of this
Agreement, except by a statement in writing signed by the party against whom
enforcement of the waiver or estoppel is sought. Any written waiver shall
operate only as to the specific term or condition waived and shall not
constitute a waiver of such term or condition for the future or as to any act
other than that specifically waived.

        14. Assignment. This Agreement may be assigned by Raytel to any
affiliate of Raytel or to any nonaffiliate of Raytel that shall succeed to the
business and assets of Raytel, CVI or the Business of CVI. In the event of any
such assignment, Raytel shall cause such affiliate or nonaffiliate, as the case
may be, to assume the obligations of Raytel hereunder, by a written agreement
addressed to Stockholder, concurrently with any assignment with the same effect
as if such assignee were "Raytel" hereunder. This Agreement is personal to
Stockholder, and Stockholder may not assign any rights or delegate any
responsibilities hereunder.

        15. Headings. The headings of paragraphs in this Agreement are solely
for convenience of reference and shall not control the meaning or interpretation
of any provision of this Agreement.




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        16. Counterparts. This Agreement may be executed in counterparts, each
of which shall be an original, with the same effect as if the signatures thereto
and hereto were upon the same instrument.

        IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date first written above.


                                        By:  /s/ DAVID WERTHEIMER
                                           ------------------------------------

                                        Print Name: David E. Wertheimer
                                                   ----------------------------

                                        RAYTEL MEDICAL CORPORATION


                                        By:  /s/ RICHARD F. BADER
                                           ------------------------------------

                                        Title: CHAIRMAN AND CEO
                                              ---------------------------------





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