Use of an accelerated chest pain assessment protocol in patients at intermediate risk of adverse cardiac events.

OBJECTIVE To determine the feasibility, safety and effectiveness of a structured clinical pathway for stratification and management of patients presenting with chest pain and classified as having intermediate risk of adverse cardiac outcomes in the subsequent six months. DESIGN Prospective clinical audit. PARTICIPANTS AND SETTING 630 consecutive patients who presented to the emergency department of a metropolitan tertiary care hospital between January 2000 and June 2001 with chest pain and intermediate-risk features. INTERVENTION Use of the Accelerated Chest Pain Assessment Protocol (ACPAP), as advocated by the "Management of unstable angina guidelines--2000" from the National Heart Foundation and the Cardiac Society of Australia and New Zealand. MAIN OUTCOME MEASURE Adverse cardiac events during six-month follow-up. RESULTS 409 patients (65%) were reclassified as low risk and discharged at a mean of 14 hours after assessment in the chest pain unit. None had missed myocardial infarctions, while three (1%) had cardiac events at six months (all elective revascularisation procedures, with no readmissions with acute coronary syndromes). Another 110 patients (17%) were reclassified as high risk, and 21 (19%) of these had cardiac events (mainly revascularisations) by six months. Patients who were unable to exercise or had non-diagnostic exercise stress test results (equivocal risk) had an intermediate cardiac event rate (8%). CONCLUSIONS This study validates use of ACPAP. The protocol eliminated missed myocardial infarction; allowed early, safe discharge of low-risk patients; and led to early identification and management of high-risk patients.