The ability of programmed ventricular stimulation and exercise testing to predict 1-yr mortality after acute myocardial infarction (AMI) was investigated in 228 clinically well survivors of AMI. Patients with inducible ventricular tachycardia (VT) or ventricular fibrillation (VF) had a higher mortality rate than those without inducible arrhythmias (26% vs. 6%, P < 0.001). Exercise-induced ST-segment change of 2 mm or more was associated with a higher mortality rate than ST change of < 2mm (11% vs. 4%, 0.05 < 0.10). Of patients who had both tests, 62% had no inducible ventricular tachycardia or ventricular fibrillation and ST change of < 2 mm, and only 1% died during the 1st yr. In clinically well survivors of AMI, programmed stimulation is a powerful predictor or 1st-yr, mortality; programmed stimulation and exercise testing together predict virtually all deaths within the 1st yr, and they can identify a large group of patients with a very low mortality rate.