USE OF EXERCISE ECHOCARDIOGRAPHY FOR PROGNOSTIC EVALUATION OF PATIENTS WITH KNOWN OR SUSPECTED CORONARY-ARTERY DISEASE

Objectives. This study prospectively compared the incremental prognost ic benefit of exercise echocardiography with that of exercise testing in a large cohort. Background. Exercise echocardiography is widely acc epted as a diagnostic tool, but the prognostic information provided by this test, incremental to clinical and stress testing evaluation, is ill-defined. Methods. Clinical, exercise and echocardiographic variabl es were studied in a consecutive group of 500 patients undergoing exer cise echocardiography. After exclusion of patients who underwent revas cularization within 3 months of the stress test (n = 16, 3%) and those lost to follow-up (n = 21, 4%), the remaining 463 patients (mean [+/- SD] age 57 +/- 12 years, 302 men) were follow-up for 44 +/- 11 months. Outcome was related to the exercise and echocardiographic findings, a nd the incremental prognostic benefit of exercise echocardiography was compared with that of standard exercise testing. Results. Cardiac eve nts occurred in 81 patients (17%), including 33 (7%) with spontaneous events (cardiac death, myocardial infarction and unstable angina) and 48 with late revascularizations due to progressive symptoms. In a mult ivariate Cox proportional hazards model, the likelihood of any cardiac event was increased in the presence of ischemia (relative risk [RR] 5 .06, 95% confidence interval [CI] 3.09 to 8.29, p < 0.001) and lessene d by more maximal stress, measured as percent age-predicted maximal he art rate (RR per 5% increment 0.84, 95% CI 0.77 to 0.92, p < 0.001). S pontaneous events were more strongly predicted by ischemia (RR 8.20, 9 5% CI 3.41 to 19.71, p < 0.001) and percent age-predicted maximal hear t rate (RR per 5% increment 0.78, 95% CI 0.67 to 0.91, p < 0.001). An interactive logistic regression model showed that the addition of echo cardiographic to exercise and clinical data offered incremental predic tive value. Conclusions. The presence of ischemia on the exercise echo cardiogram can predict whether patients will experience an event, This relation is independent of, and incremental to, clinical and exercise data. (C) 1997 by the American College of Cardiology.