Prediction of cardiac mortality after myocardial infarction: The role of maximal treadmill stress echocardiography

Patients frequently undergo low-level exercise treadmill testing after acute myocardial infarction (MI) and, in the absence of inducible ischemia, a maximal test several weeks later. This study examines 203 patients who had 2-dimensional echocardiography before and after a maximal Bruce protocol exercise treadmill test performed 4 to 6 weeks after MI. The subjects were followed for a mean of 43 months (range 1 to 77 months). Predictors of cardiac mortality by multivariate or univariate analysis included an ejection fraction ≤40%, diabetes, age >70 years, and ischemia by exercise echocardiography but not by electrocardiog raphy. Therefore, standard electrocardiographic monitoring during exercise treadmill testing 6 weeks after MI fails to predict cardiac mortality. The addition of pre-exercise and post-exercise treadmill stress echo-cardiography to readily available clinical parameters identifies those patients at greatest risk for cardiac death (resting ejection fraction ≤40%) and detects residual exercise-induced ischemia that may be of additional prognostic value.