Submaximal early exercise test compared to clinical findings for evaluation of short- and long-term prognosis after the first myocardial infarction. Result from the MONICA Projects in Augsburg and Toulouse.

Abstract

Clinical and ergometric data were derived from 1098 consecutive exercise tests in patients with a first acute myocardial infarction between 1974-1983. In 1992 a follow-up was performed in order to analyse the importance of a submaximal early exercise test, in combination with clinical data, for the prediction of short- and long-term prognosis of cardiovascular death. The relative value of 20 clinical variables, including medical history, markers of infarction size, medication etc., and 28 variables at exercise test were studied. Univariate, multivariate and survival analysis, for estimation of prognosis and independent prediction of cardiovascular death was used. Independent clinical risk factors for cardiovascular death were (1) Within 1 year: relative heart volume (ml.m-2 body surface area) on chest X-ray. (2) Long-term mortality: maximum heart rate and relative heart volume, diabetes, age and digitalis medication. Independent exercise risk factors were: (1) Within 1 year: heart rate, ventricular arrhythmia and ST depression > or = 1 mm before exercise, diastolic blood pressure at maximum exercise and target heart rate. (2) Long-term mortality: angina pectoris and/or ST depression > or = 1 mm at maximum exercise. In subgroups of patients with clinical risk factors, mortality risk increased if there were signs of angina pectoris and/or ST depression > or = 1 mm during exercise. The risk increased 100% in diabetics, 91% with age > 70 years, 58% with relative heart volume > or = 500 ml.m-2 body surface area, 42% with heart rate > or = 100 at admission, and 34% with digitalis medication. No increase was found in the subgroup of patients without clinical risk factors. Thus, submaximal early exercise stress testing provides important information for short- and long-term prognosis in patients after the first acute myocardial infarction compared to clinical evaluation alone.