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                                                                    EXHIBIT 31.2

       CERTIFICATION OF CHIEF FINANCIAL OFFICER PURSUANT TO RULE 13a-14(a)
                   UNDER THE SECURITIES EXCHANGE ACT OF 1934

I, Michael K. Matysik, certify that:

         1.       I have reviewed this quarterly report on Form 10-Q of Quinton
     Cardiology Systems, Inc.;

         2.       Based on my knowledge, this quarterly report does not contain
     any untrue statement of a material fact or omit to state a material fact
     necessary to make the statements made, in light of the circumstances under
     which such statements were made, not misleading with respect to the period
     covered by this quarterly report;

         3.       Based on my knowledge, the financial statements, and other
     financial information included in this quarterly report, fairly present in
     all material respects the financial condition, results of operations and
     cash flows of the registrant as of, and for, the periods presented in this
     quarterly report;

         4.       The registrant's other certifying officer and I are
     responsible for establishing and maintaining disclosure controls and
     procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for
     the registrant and have:

         a)       Designed such disclosure controls and procedures to ensure
     that material information relating to the registrant, including its
     consolidated subsidiaries, is made known to us by others within those
     entities, particularly during the period in which this quarterly report is
     being prepared;

         b)       Evaluated the effectiveness of the registrant's disclosure
     controls and procedures and presented in this report our conclusions about
     the effectiveness of the disclosure controls and procedures, as of the end
     of the period covered by this report based on such evaluation; and

         c)       Disclosed in this report any change in the registrant's
     internal control over financial reporting that occurred during the
     registrant's most recent fiscal quarter (the registrant's fourth fiscal
     quarter in the case of an annual report) that has materially affected, or
     is reasonably likely to materially affect, the registrant's internal
     control over financial reporting.

         5.       The registrant's other certifying officer and I have
     disclosed, based on our most recent evaluation of internal control over
     financial reporting, to the registrant's auditors and the audit committee
     of registrant's board of directors (or persons performing the equivalent
     function):

         a)       All significant deficiencies and material weaknesses in the
     design or operation of internal control over financial reporting which are
     reasonably likely to adversely affect the registrant's ability to record,
     process, summarize and report financial information; and

         b)       Any fraud, whether or not material, that involves management
     or other employees who have a significant role in the registrant's internal
     control over financial reporting.

         Date: November 14, 2003

                                 /s/ Michael K. Matysik
                               ---------------------------
                               Michael K. Matysik
                               Senior Vice President and Chief Financial Officer