Incremental prognostic value of stress echocardiography as an adjunct to exercise electrocardiography after uncomplicated myocardial infarction

Objective-To assess the prognostic value of stress echocardiography as an a djunct to exercise electrocardiography in patients with uncomplicated acute myocardial infarction. Design-496 patients underwent a maximum exercise ECG and pharmacological st ress echocardiography (406 dobutamine and 90 dipyridamole) within 15 days o f uncomplicated acute myocardial infarction and were followed for a mean of 25 months (range 1-74 months) for reinfarction, unstable angina, and cardi ac death. Patients undergoing re vascularisation were omitted. Results-Exercise ECG was positive in 162 patients (32.6%) and low threshold positive (< 100 W) in 91 (18%). Stress echocardiography was positive in 23 9 patients (48%) (194 with dobutamine and 45 with dipyridamole stress). The agreement between the two tests was 63% (<kappa> = 0.24, 95% confidence in terval 0.15 to 0.33). Sixty nine spontaneous events occurred (14 cardiac de aths, 26 reinfarctions, and 29 with unstable angina requiring hospital admi ssion), and 126 patients underwent: revascularisation (39 coronary angiopla sty and 87 bypass surgery). By receiver operating characteristic curve anal ysis, stress echocardiography provided incremental prognostic information c ompared with clinical data. A low threshold positive exercise ECG was assoc iated with a worse outcome, but there was a fivefold increase in risk in pa tients with positive stress echocardiography who also had a high threshold (> 100 W) positive exercise EGG. Event-free survival of patients with both rests positive was significantly less than in patients with only one positi ve test or with both tests negative. Conclusions-Stress echocardiography provides additional prognostic informat ion after uncomplicated acute myocardial infarction, but the greatest gain is found in patients with a high threshold positive exercise EGG.