Exercise stress testing in the post-myocardial infarction patient

Abstract

Recent studies indicate that predischarge evaluation of the post-myocardial infarction (MI) patient is important in predicting their subsequent course and the need for specific treatment. Left ventricular function, residual ischemia and the tendency toward ventricular arrhythmias can all be assessed noninvasively in the late hospital phase. Stress testing is 1 of the most useful and widely available of these techniques. An impaired hemodynamic response to exercise expressed by excessive tachycardia, plateau or falling blood pressure or reduced work load capacity suggests an increased risk of recurrent cardiac events in the near future. Angina or electrocardiographic abnormalities, including arrhythmias, also indicate a less favorable outcome. A good performance in a post-MI stress test is associated with a relatively good prognosis. The exercise electrocardiogram, therefore, appears to be a useful screening device for evaluating post-MI patients. Other noninvasive tests such as radionuclide ventriculography, exercise thallium scanning, Holter monitoring and echocardiography greatly augment the predictive value of exercise electrocardiography, and a patient profile should be developed using all the available clinical and laboratory data. Patients with a poor prognostic profile may then undergo further testing, such as coronary angiography, and their subsequent therapy modified appropriately.