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                                                                   Exhibit 10.75

                       KEY MANAGEMENT RETENTION AGREEMENT

        THIS KEY MANAGEMENT RETENTION AGREEMENT (the "Agreement"), dated as of
February 6, 2002 (the "Effective Date"), is made and entered into by and between
RAYTEL MEDICAL CORPORATION, a Delaware corporation (the "Company"), and SWAPAN
SEN (the "Executive").

                                    RECITALS:

        A. The Executive is currently employed as the Company's Senior Vice
President, and President of the Company's subsidiary, Raytel Imaging Holdings,
Inc. ("RIH"), pursuant to a written employment agreement dated as of March 1,
1998 (the "Employment Agreement");

        B. The Company is considering various potential strategic transactions
that could result in a Change of Control (as hereinafter defined);

        C. Pursuant to a resolution adopted on December 19, 2001, the Board of
Directors approved a supplement to the Employment Agreement to provide
additional incentive for the continued employment of the Executive in order to
facilitate a potential Change of Control; and

        D. The parties now desire to enter into an agreement confirming such
incentive arrangements.

        NOW, THEREFORE, the parties agree as follows:

        1. Definitions. For purposes of this Agreement, the following terms
shall be defined as follows:

               1.1 "Cause" shall exist in the event of the Executive's (i)
willful and repeated neglect of his duties as an employee of the Company (other
than as a result of a physical disability not related to substance abuse), (ii)
conviction of a crime involving moral turpitude, (iii) commission of any act of
fraud or dishonesty against the Company, or (iv) breach of the Executive's
obligations under the Employment Agreement or the Proprietary Information and
Inventions Agreement between the Executive and the Company which, if curable, is
not cured within ten (10) days following notice of such breach by the Company.

               1.2 A "Change of Control" of the Company shall occur upon: (i) a
merger, consolidation or other reorganization involving the Company, or a tender
offer, exchange offer or other transaction or series of transactions involving
the acquisition of securities of the Company where, in any such case, the
holders of voting securities of the Company immediately prior to such
transaction or series of transactions own less than 50% of the voting securities
of the surviving or successor entity, or its parent, immediately following such
transaction or series of transactions; (ii) the sale of all or substantially all
of the Company's assets; or (iii) the sale of all or substantially all of the
capital stock or assets of RIH.

               1.3 "Good Reason" shall exist in the event that, other than under
circumstances involving Cause or the Executive's total disability (as defined
pursuant to the Company's long-term disability insurance plan covering the
Executive if any such plan is then in


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effect, or otherwise as determined by the Company's Board of Directors), the
Company, without the Executive's prior written consent; (i) materially alters or
reduces the Executive's duties, responsibilities and status with the Company
from those which exist as of the Effective Date of this Agreement; (ii) assigns
the Executive duties which are inconsistent with the Employee's position as
Senior Vice President of the Company and President of RIH; (iii) materially
breaches the terms of the Employment Agreement in respect to the payment of
compensation or benefits or in any other material respect and such breach is not
cured within ten days after notice thereof; (iv) requires the Employee, as a
condition to his continued employment, to be based more than 100 miles from the
location where he is based as of the Effective Date; or (v) requires the
Employee, as a condition to his continued employment, to perform illegal or
fraudulent acts or omissions.

        2. Retention and Severance Arrangement.

               2.1 Retention Bonus. In the event the Company effects a Change of
Control during the term of this Agreement, the Executive shall be entitled to
receive a cash bonus (the "Retention Bonus") in the amount of $350,000, payable
in a single lump sum promptly upon the fulfillment of the conditions set forth
in Section 2.2. The Executive may elect to reduce the Retention Bonus by an
amount that will reduce or eliminate any excise tax liability under Section 280G
of the Internal Revenue Code of 1986, as amended.

               2.2 Conditions to Receipt of Retention Bonus.

                      (a) In order for the Executive to be eligible to receive
the Retention Bonus, the following conditions must be met:

                             (i) The Executive must be continuously employed by
the Company on a full-time basis between the Effective Date of this Agreement
and the effective date of the Change of Control; and

                             (ii) Either of the following conditions must occur:
(A) the Executive remains continuously employed by the Company, RIH, the
acquiring entity or another subsidiary or affiliate of the acquiring entity
during the 12-month period following the effectiveness of the Change of Control;
or (B) prior to the end of such 12-month period, the Executive's employment by
one of such entities is terminated involuntarily by such entity other than for
Cause or voluntarily by the Executive with Good Reason.

               2.3 Reduction. The Retention Bonus payable to the Executive shall
not be reduced by any severance payments paid or payable to the Executive under
the terms of the Employment Agreement.

               2.4 Acceleration of Option Vesting. The option agreements between
the Company and the Executive shall be amended to provide that the vesting
provisions of all outstanding options to purchase the Company's Common Stock
held by the Executive shall be accelerated so that such options will vest and
become exercisable, in full, upon the Change of Control, to the extent any such
option agreements do not currently provide for such acceleration of vesting.


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               2.5 Annual Bonus. The Retention Bonus is not intended to replace
or reduce any bonus to which the Executive may be entitled under the Company's
existing annual incentive bonus program, which shall continue to be administered
in accordance with the Company's existing policies.

               2.6 Term. The term of this Agreement shall be twelve (12)
calendar months from the Effective Date of this Agreement.

        3. General

               3.1 Successors and Assigns. The provisions of this Agreement
shall inure to the benefit of and be binding upon the Company, the Executive and
each and all of their respective heirs, legal representatives, successors and
assigns. The duties, responsibilities and obligations of the Executive under
this Agreement shall be personal and not assignable or delegable by the
Executive in any manner whatsoever to any person, corporation, partnerships,
firm, company, joint venture or other entity. The Executive may not assign,
transfer, convey, mortgage, pledge or in any other manner encumber the
compensation or other benefits to be received by him or any rights which he may
have pursuant to the terms and provisions of this Agreement. The Company
covenants and agrees to require that any successor to the Company through a
Change of Control shall agree to honor the obligations of the Company under this
Agreement.

               3.2 Waiver. No waiver of any breach of any warranty,
representation, agreement, promise, covenant, paragraph, term or provision of
this Agreement shall be deemed to be a waiver of any preceding or succeeding
breach of the same or any other warranty, representation, agreement, promise,
covenant, paragraph, term or provision of this Agreement. No extension of the
time for the performance of any obligation or other act required or permitted by
this Agreement shall be deemed to be an extension of the time of the performance
of any other obligation or any other act required or permitted by this
Agreement.

               3.3 Entire Agreement. This Agreement, and the other agreements
referred to herein, including the Employment Agreement and the Company's benefit
plans, are the sole, complete and entire contract, agreement and understanding
between the Company and the Executive concerning the subject matter hereof.
Except as provided in the Employment Agreement or such benefit plans or as
otherwise provided herein, this Agreement supersedes any and all prior
contracts, agreements, plans, agreements in principle, correspondence, letters
of intent, understandings, and negotiations, whether oral or written, concerning
the subject matter hereof.

               3.4 Amendments. No amendment, modification, waiver, or consent
relating to this Agreement will be effective unless and until it is embodied in
a written document signed by the Company and by the Executive.

               3.5 Counterparts. The Agreement may be executed by the Company
and by the Executive in counterparts, each of which shall be deemed an original
and which together shall constitute one instrument.


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               3.6 Headings. The headings contained in this Agreement are for
reference purposes only and shall not in any manner whatsoever affect the
construction or interpretation of this Agreement or be deemed a part of this
Agreement for any purpose whatsoever.

               3.7 Severability. To the extent that any section, term,
provision, sentence, phrase, clause or word of this Agreement shall be found to
be illegal or unenforceable for any reason, such section, term, provision,
sentence, phrase, clause or word shall be modified or deleted in such a manner
as to make this Agreement, as so modified, legal and enforceable under
applicable laws. The remainder of this Agreement shall continue in full force
and effect.

               3.8 Applicable Law. This Agreement and each and every provision
of this Agreement shall be interpreted solely pursuant to the internal laws of
the State of California without regard to any conflicts of law principles
thereof.

               3.9 Construction. The language of this Agreement shall for all
purposes be construed as a whole, according to its fair meaning, not strictly
for or against the Executive or the Company, without regard to the identity or
status of any person or persons who drafted all or any portion of this
Agreement.

               3.10 Notices. Any notices to be given pursuant to this Agreement
by either party to the other party may be effected by personal delivery or by
registered or certified mail, postage prepaid with return receipt requested.
Mailed notices shall be addressed to the parties at the addresses stated below,
but each party may change its or his address by written notice to the other in
accordance with this Section 3.10. Notices delivered personally shall be deemed
received on the date of delivery. Notices delivered by mail shall be deemed
received on the third business day after the mailing thereof.

        Mailed notices to the Executive shall be addressed as follows:

               Swapan Sen
               63 Bunning Drive
               Voorkees, N.J. 08043

        Mailed notices to the Company shall be addressed as follows:

               Raytel Medical Corporation
               2755 Campus Drive, Suite 200
               San Mateo, California 94403-2515
               Attention:  Chief Executive Officer

               3.11 Arbitration. Any and all controversies, disputes and/or
claims in any manner arising out of or relating to this Agreement shall be
settled solely be arbitration in accordance with the Commercial Arbitration
Rules of the American Arbitration Association. Such arbitration proceeding shall
take place in the state and county of the Company's office where the Executive
is based. Judgment on any decision rendered by the arbitrator may be entered in
any court having jurisdiction thereof. Each party shall bear its own attorney's
fees and expenses and other costs in any arbitration proceeding. All
administrative fees and the fee of the


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arbitrator shall be borne by the parties equally. The arbitration provisions set
forth in this Section 3.11 are intended by the Executive and by the Company to
be absolutely exclusive for all purposes whatsoever, and applicable to each and
every controversy, dispute or claim in any manner arising out of or relating to
this Agreement, the meaning, application or interpretation of this Agreement,
any breach or claimed breach thereof or any voluntary or involuntary termination
of this Agreement with or without cause, including, without limitation, any such
controversy, dispute or claim which, if pursued through any state or federal
court or administrative agency, would arise at law, in equity or pursuant to
statutory, regulatory or common law rules, regardless of whether such dispute,
controversy or claim would arise in or from contract, tort or any other legal or
equitable theory or basis.

        IN WITNESS WHEREOF, the Company and the Executive have executed this
Agreement as of the date first set forth above.


RAYTEL MEDICAL CORPORATION


By:____________________________________     ___________________________________
   Richard F. Bader                         Swapan Sen
   Chairman and Chief Executive Officer




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