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                                                                    EXHIBIT 31.2

  CERTIFICATION OF CHIEF FINANCIAL OFFICER PERSUANT TO RULE 13a-14(a) UNDER THE
          SECURITIES EXCHANGE ACT OF 1934 OF ITEM 601 OF REGULATION S-K

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: August 14, 2003

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