Post-myocardial infarction exercise testing: clinical significance of a left ventricular function index and ventricular arrhythmias. A prospective study.

A predischarge exercise test was performed in a prospective series of 187 patients, less than 70 years old, with acute myocardial infarction. A survival analysis confirmed previous retrospective findings of a significantly increased long-term mortality in patients with a low increase in the pressure-rate-product (PRP) and/or with major exercise-induced arrhythmias. ST segment depression was without prognostic significance. By a graduated, quantitative re-evaluation of the significance of exercise-induced ventricular arrhythmias, an appropriate, significantly discriminating cutoff point for the frequency of solitary ventricular premature beats (VPBs) was found at two or more VPBs/min. Repetitive VPBs had an equal significance. The probability of 4.5-year survival in patients with these arrhythmias and a low increase in PRP was 0.49 vs. 0.85 in patients with less frequent arrhythmias and with a high increase in PRP (p less than 10(-6)).