Safety and utility of exercise testing in emergency room chest pain centers: An advisory from the Committee on Exercise, Rehabilitation, and Prevention, Council on Clinical Cardiology, American Heart Association.

Abstract

Rapid triage and management of patients with an acute chest pain syndrome is an integral part of routine emergency room clinical activities. Specialized chest pain centers have been developed to better risk stratify patients in the emergency department setting using noninvasive test protocols to cost-effectively identify those patients who can be safely discharged with an acceptably low risk of cardiac events. 1‐16 The aim of this report is to summarize and interpret the evidence regarding the safety and utility of exercise testing in the evaluation of patients with chest pain who present to the emergency department. The rationale for implementation of a chest pain unit in the emergency department, use of different noninvasive test procedures and serum markers, and patient treatment will not be reviewed in detail except as they pertain to the use of exercise testing. Historical Perspective The role of exercise testing after stabilization of hospitalized patients with unstable angina has been extensively described. 17‐28 Swahn et al 23 reported on 400 patients ,65 years of age who underwent symptom-limited predischarge exercise testing after stabilization of unstable angina using an electrically braked bicycle ergometer starting at 10 W with continuous load increases of 10 W/min. The incidence of exercise-induced ST-segment depression $ 1m m was 33% in 272 men and 116 women. An abnormal exercise electrocardiogram (ECG) was recorded in 51% to 53% of patients with an abnormal ECG at rest versus 16% to 19% when the resting ECG was normal. Peak workload achieved was greater in men than in women, although the peak rate-pressure product was similar. After 1 year, there were 49 cardiac events in the 276 men who performed the exercise test compared with only 5 cardiac events in the 118 women.24 Exercise-induced ST-segment depression and low peak rate-pressure product independently identified risk of myocardial infarction or cardiac death. Exercise test variables were not predictive of cardiac events for the women enrolled in this study. Madsen et al25 reported on 257 patients stabilized for unstable angina, 26 of whom had a cardiac death or nonfatal myocardial infarction over a median 14-month follow-up. The presence of ST depression or negative T waves on the resting ECG or exerciseinduced ST depression or angina during the exercise test was predictive of cardiac events. Severi et al 26 reported on 374 patients who had an exercise stress test and underwent coronary angiography during the same admission. In the 54 patients with a normal rest and normal exercise ECG, only 4% of patients had 3-vessel coronary disease, and no patient had left main disease; 8-year survival was 100%. In the 86 patients with a normal resting ECG but abnormal exercise ECG, 3-vessel or left main coronary disease was present in 22% and 9%, respectively; 8-year survival was 97%. In the 59 patients with an abnormal resting ECG and normal exercise ergometry study, 3-vessel or left main coronary disease was noted in 19% of patients; 8-year survival was 88%. In the 175 patients with an abnormal rest and abnormal exercise ECG, only 2% of patients had normal vessels; 3-vessel or left main coronary disease was noted in 41% and 12%, respectively; 8-year survival was 70%. Similar prognostic findings were reported by Fruergaard et al.27