Prognostic value of electrocardiographic exercise testing and noninvasive assessment of left ventricular ejection fraction soon after acute myocardial infarction.

To determine the relative value of clinical findings, results of low-level treadmill electrocardiographic (ECG) exercise testing and left ventricular (LV) ejection fraction (EF) for predicting cardiac events in the year after an acute myocardial infarction (AMI), 72 patients who had had an uncomplicated AMI were studied with either radionuclide angiography or 2-dimensional echocardiography to assess LVEF and a low-level treadmill exercise test before hospital discharge. All patients were followed for 1 year. Nineteen patients (26%) had at least 1 cardiac event: coronary artery bypass grafting (11 patients), recurrent AMI (6 patients) or cardiac death (6 patients). Multiple logistic regression analysis revealed that total cardiac events were predicted by exercise ECG ST-segment depression or angina, prior AMI, ventricular ectopic activity during exercise and digoxin therapy (cumulative r = 0.58, p less than 0.001). Coronary artery bypass grafting was predicted by exercise ECG ST-segment depression or angina (r = 0.29, p = 0.01). Recurrent AMI was predicted by exercise ECG ST-segment depression or angina, prior AMI and ventricular ectopic activity during exercise (cumulative r = 0.49, p less than 0.001). Cardiac death was predicted by an LVEF of 40% or less (r = 0.38, p = 0.01). The presence of both an LVEF of 40% or less and ECG ST-segment depression on treadmill exercise testing defined a subgroup of patients with a high incidence of early cardiac death (33%).(ABSTRACT TRUNCATED AT 250 WORDS)