[Long-term prognosis in patients with exercise-induced ST-segment elevation after myocardial infarction]

The present study investigated whether the exercise-induced ST-segment elevation can predict the prognosis for patients with myocardial infarction. Among 529 patients with myocardial infarction, 411 underwent treadmill exercise testing about 5 weeks after the onset. All patients were followed up (mean [+/-SD] 54 +/- 41 months) to compare the incidence of cardiac events. One hundred and eighteen patients (22%) could not perform the exercise test due to cardiac or noncardiac limitation. Ineligibility for exercise test was most useful for risk stratification. Multivariate analysis showed that elimination from the stress test with cardiac limitation was the most significant predictor for cardiac death. Excluding the 16 patients with bundle branch block, the 395 patients were classified into four groups of ST-segment elevation (107 cases, 27%), ST-segment elevation combined with depression (22 cases, 6%), ST-segment depression (106 cases, 27%), ST-segment unchanged (160 cases, 40%). Among the various stress test abnormalities, only low exercise duration was a predictor for cardiac death. ST-depression and ST-elevation combined with depression were independent risk predictors for all cardiac events. Most patients with ST-elevation had single-vessel disease with excellent exercise capacity and low incidence of cardiac events. ST-segment elevation during exercise 5 weeks after myocardial infarction is not associated with a poor prognosis.