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                                                                   EXHIBIT 10.20

                    INTELLECTUAL PROPERTY SECURITY AGREEMENT

         This Intellectual Property Security Agreement is entered into as of
January 9, 2003 by and between SILICON VALLEY BANK ("Secured Party") and
Burdick, Inc. (jointly and severally, the "Grantor").

                                    RECITALS

         A.       Secured Party and Grantor are entering into that certain
Assumption Agreement of even date herewith pursuant to which Grantor has assumed
the "Obligations" arising out of that certain Loan and Security Agreement dated
December 30, 2002 between Quinton Cardiology Systems, Inc., Quinton Inc. and
Secured Party (as the same may be amended, modified or supplemented from time to
time, the "Loan Agreement"; capitalized terms used herein which are not defined,
have the meanings set forth in the Loan Agreement).

         B.       Pursuant to the terms of the Loan Agreement, Grantor has
granted to Secured Party a security interest in all of Grantor's right, title
and interest, whether presently existing or hereafter acquired, in, to all
Intellectual Property and all other Collateral.

         NOW, THEREFORE, as collateral security for the payment and performance
when due of all of the Obligations, Grantor hereby grants, represents, warrants,
covenants and agrees as follows:

                                    AGREEMENT

         1.       Grant of Security Interest. To secure all of the Obligations,
Grantor grants and pledges to Secured Party a security interest in all of
Grantor's right, title and interest in, to and under its Intellectual Property
(as defined in the Loan Agreement), including without limitation the following:

                  (a)      All of present and future United States registered
copyrights and copyright registrations, including, without limitation, the
registered copyrights, maskworks, software, computer programs and other works of
authorship subject to United States copyright protection listed in Exhibit A-1
to this Agreement (and including all of the exclusive rights afforded a
copyright registrant in the United States under 17 U.S.C. Section 106 and any
exclusive rights which may in the future arise by act of Congress or otherwise)
and all present and future applications for copyright registrations (including
applications for copyright registrations of derivative works and compilations)
(collectively, the "Registered Copyrights"), and any and all royalties,
payments, and other amounts payable to Grantor in connection with the Registered
Copyrights, together with all renewals and extensions of the Registered
Copyrights, the right to recover for all past, present, and future infringements
of the Registered Copyrights, and all computer programs, computer databases,
computer program flow diagrams, source codes, object codes and all tangible
property embodying or incorporating the Registered Copyrights, and all other
rights of every kind whatsoever accruing thereunder or pertaining thereto.

                  (b)      All present and future copyrights, maskworks,
software, computer programs and other works of authorship subject to (or capable
of becoming subject to) United States copyright protection which are not
registered in the United States Copyright Office (the

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"Unregistered Copyrights"), whether now owned or hereafter acquired, including
without limitation the Unregistered Copyrights listed in Exhibit A-2 to this
Agreement, and any and all royalties, payments, and other amounts payable to
Grantor in connection with the Unregistered Copyrights, together with all
renewals and extensions of the Unregistered Copyrights, the right to recover for
all past, present, and future infringements of the Unregistered Copyrights, and
all computer programs, computer databases, computer program flow diagrams,
source codes, object codes and all tangible property embodying or incorporating
the Unregistered Copyrights, and all other rights of every kind whatsoever
accruing thereunder or pertaining thereto. The Registered Copyrights and the
Unregistered Copyrights collectively are referred to herein as the "Copyrights."

                  (c)      All right, title and interest in and to any and all
present and future license agreements with respect to the Copyrights.

                  (d)      All present and future accounts, accounts receivable,
royalties, and other rights to payment arising from, in connection with or
relating to the Copyrights.

                  (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 set forth on Exhibit B attached
hereto (collectively, the "Patents");

                  (f)      All 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 Grantor connected
with and symbolized by such trademarks, including without limitation those set
forth on Exhibit C attached hereto (collectively, the "Trademarks");

                  (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 rights identified above;

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

                  (i)      All amendments, extensions, renewals and extensions
of any of the Copyrights, Trademarks or Patents; 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, and all license royalties and
proceeds of infringement suits, and all rights corresponding to the foregoing
throughout the world and all re-issues, divisions continuations, renewals,
extensions and continuations-in-part of the foregoing.

         2.       Loan Agreement. This security interest is granted in
conjunction with the security interest granted to Secured Party under the Loan
Agreement. The rights and remedies of Secured Party with respect to the security
interest granted hereby are in addition to those set forth in the Loan Agreement
and the other Loan Documents, and those which are now or hereafter available

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to Secured Party as a matter of law or equity. Each right, power and remedy of
Secured Party provided for herein or in the Loan Agreement or any of the other
Loan Documents, or now or hereafter existing at law or in equity shall be
cumulative and concurrent and shall be in addition to every right, power or
remedy provided for herein and the exercise by Secured Party of any one or more
of the rights, powers or remedies provided for in this Agreement, the Loan
Agreement or any of the other Loan Documents, or now or hereafter existing at
law or in equity, shall not preclude the simultaneous or later exercise by any
person, including Secured Party, of any or all other rights, powers or remedies.

         3.       Covenants and Warranties. Grantor represents, warrants,
covenants and agrees as follows:

                  (a)      Grantor has no present maskworks, software, computer
programs and other works of authorship registered with the United States
Copyright Office except as disclosed on Exhibit A-1 hereto.

                  (b)      Grantor shall undertake all reasonable measures to
cause its employees, agents and independent contractors to assign to Grantor all
rights of authorship to any copyrighted material in which Grantor has or may
subsequently acquire any right or interest.

                  (c)      Grantor shall promptly advise Secured Party of any
Trademark, Patent or Copyright not specified in this Agreement, which is
hereafter acquired by Grantor.

                  (d)      Grantor shall not register any maskworks, software,
computer programs or other works of authorship subject to United States
copyright protection with the United States Copyright Office without first
complying with the following: (i) providing Secured Party with at least 15 days
prior written notice thereof, (ii) providing Secured Party with a copy of the
application for any such registration and (iii) executing and filing such other
instruments, and taking such further actions as Secured Party may reasonably
request from time to time to perfect or continue the perfection of Secured
Party's interest in the Collateral, including without limitation the filing with
the United States Copyright Office, simultaneously with the filing by Grantor of
the application for any such registration, of a copy of this Agreement or a
Supplement hereto in form acceptable to Secured Party identifying the maskworks,
software, computer programs or other works of authorship being registered and
confirming the grant of a security interest therein in favor of Secured Party.

         4.       General. If any action relating to this Agreement is brought
by either party hereto against the other party, the prevailing party shall be
entitled to recover reasonable attorneys fees, costs and disbursements. This
Agreement may be amended only by a written instrument signed by both parties
hereto. To the extent that any provision of this Agreement conflicts with any
provision of the Loan Agreement, the provision giving Secured Party greater
rights or remedies shall govern, it being understood that the purpose of this
Agreement is to add to, and not detract from, the rights granted to Secured
Party under the Loan Agreement. This Agreement, the Loan Agreement, and the
other Loan Documents comprise the entire agreement of the parties with respect
to the matters addressed in this Agreement. This Agreement shall be governed by
the laws of the State of California, without regard for choice of law
provisions. Grantor and Secured Party consent to the nonexclusive jurisdiction
of any state or federal court located in Santa Clara

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County, California.

         5.       WAIVER OF RIGHT TO JURY TRIAL. SECURED PARTY AND GRANTOR EACH
HEREBY WAIVE THE RIGHT TO TRIAL BY JURY IN ANY ACTION OR PROCEEDING BASED UPON,
ARISING OUT OF, OR IN ANY WAY RELATING TO: (I) THIS AGREEMENT; OR (II) ANY OTHER
PRESENT OR FUTURE INSTRUMENT OR AGREEMENT BETWEEN SECURED PARTY AND GRANTOR; OR
(III) ANY CONDUCT, ACTS OR OMISSIONS OF SECURED PARTY OR GRANTOR OR ANY OF THEIR
DIRECTORS, OFFICERS, EMPLOYEES, AGENTS, ATTORNEYS OR ANY OTHER PERSONS
AFFILIATED WITH SECURED PARTY OR GRANTOR; IN EACH OF THE FOREGOING CASES,
WHETHER SOUNDING IN CONTRACT OR TORT OR OTHERWISE.

         IN WITNESS WHEREOF, the parties have cause this Intellectual Property
Security Agreement to be duly executed by its officers thereunto duly authorized
as of the first date written above.

Address of Grantor:                           Grantor:

3303 Monte Villa Parkway                      Burdick, Inc.
Bothell, WA  98021

                                              By: /s/ Michael Matysik
                                                 -------------------------------
                                              Title:  SVP / CFO / Secretary
                                              Name:   Michael Matysik

Address of Secured Party:                     Secured Party:

3003 Tasman Drive                             SILICON VALLEY BANK
Santa Clara, California  95054

                                              By: /s/ Silicon Valley Bank
                                                 -------------------------------
                                              Title:____________________________

Form: 3/1/02
Document Version: -0

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                                   EXHIBIT A-1

                              REGISTERED COPYRIGHTS
 (including copyrights that are the subject of an application for registration)

<TABLE>
<CAPTION>
                      Registration/            Registration/
                       Application              Application
Description              Number                    Date
-----------              ------                    ----
<S>                   <C>                      <C>
</TABLE>

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                                   EXHIBIT A-2

                             UNREGISTERED COPYRIGHTS

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                                    EXHIBIT B

                                     PATENTS

<TABLE>
<CAPTION>
                      Registration/            Registration/
                       Application              Application
Description              Number                    Date
-----------              ------                    ----
<S>                   <C>                      <C>
</TABLE>

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                                    EXHIBIT C

                                   TRADEMARKS

<TABLE>
<CAPTION>
                      Registration/            Registration/
                       Application              Application
Description              Number                    Date
-----------              ------                    ----
<S>                   <C>                      <C>
</TABLE>