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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: April 27, 2004

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

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