Dobutamine-atropine stress echocardiography and clinical data for predicting late cardiac events in patients with suspected coronary artery disease.

PURPOSE To compare the relative value of clinical variables with dobutamine-atropine stress echocardiography to predict cardiac events during long-term follow-up. Dobutamine stress echocardiography is increasingly used for the detection of coronary artery disease, but little is known of its prognostic value. PATIENTS AND METHODS A total of 430 patients (310 men; mean age 61 years, range 22 to 90) were enrolled in the study. Patients were referred for chest pain complaints and were unable to perform an adequate exercise stress test. All patients underwent dobutamine-atropine stress test (incremental dobutamine infusion: 10 to 40 micrograms/kg/minute, continued with atropine 0.25 to 1 mg intravenously if necessary to achieve 85% of the age predicted maximal heart rate, without symptoms or signs of ischemia) and clinical cardiac evaluation. Follow-up was 17 +/- 5 months, with a minimum of 6 months; 3 patients were lost to follow-up. Cardiac events were defined as cardiac death, nonfatal myocardial infarction, and coronary revascularization. RESULTS Seventy-nine cardiac events occurred in 76 patients: cardiac death (n = 11), nonfatal myocardial infarction (n = 18), and coronary revascularization (n = 50). By multivariate regression analysis, the prognostic value of the stress test in addition to common clinical variables was assessed. (1) Cardiac death was predicted by age greater than 70 years (odds ratio 5.6, 1.5 to 20) or new wall motion abnormalities in a study that is normal at rest (odds ratio 4.1, 1.1 to 15). (2) Death or myocardial infarction was predicted by a history of myocardial infarction (odds ratio 4.8, 1.8 to 13) or age greater than 70 years (odds ratio 2.3, 1.1 to 5.4), and the stress test outcome provided no additional information. (3) If all events were combined, only stress test results were prognostic: new wall motion abnormalities in a study that is normal at rest (odds ratio 3.1, 1.9 to 5.1), wall motion abnormalities at rest (wall motion score at rest > or = 1.12) (odds ratio 2.5, 1.4 to 4.0), or any new wall motion abnormalities during stress (odds ratio 2.0, 1.4 to 3.8). The positive predictive value of any new wall motion abnormality during stress for all late cardiac events was 25% (95% confidence interval [CI] 19 to 31) with a negative predictive value of 87% (95% CI 83 to 91). CONCLUSION In a large cohort of unselected patients with chest pain syndromes, new wall motion abnormalities induced by dobutamine provide additional information for late cardiac events, independent of clinical variables.