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                                                                    EXHIBIT 31.2

       CERTIFICATION OF CHIEF FINANCIAL OFFICER PURSUANT TO SECTION 302(a)
                        OF THE SARBANES-OXLEY ACT OF 2002

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 we 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: July 30, 2004

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