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

Patients frequency undergo low-level exercise treadmill testing after acute myocardial infarction (MI) and in the absence of inducible ischemia, a max imal test several weeks later. This study examines 203 patients who had 2-d imensional echocardiography before and after a maximal Bruce protocol exerc ise treadmill test performed 4 to 6 weeks after MI. The subjects were follo wed for a mean of 43 months (range 1 to 77 months). Predictors of cardiac m ortality by multivariate or univariate analysis included an ejection fracti on less than or equal to 40%, diabetes, age >70 years, and ischemia by exer cise echocardiography but not by electrocardiography. Therefore, standard e lectrocardiographic monitoring during exercise treadmill testing 6 weeks af ter MI fails to predict cardiac mortality. The addition of pre-exercise and post-exercise treadmill stress echocardiography to readily available clini cal parameters identifies those patients at greatest risk for cardiac death (resting ejection fraction less than or equal to 40%) and detects residual exercise-induced ischemia that may be of additional prognostic value.