Electrophysiologic Testing to Identify High-Risk Patients After Acute Myocardial Infarction

Abstract

Many patients who survive the acute phase of a myocardial infarction are at risk of sudden cardiac death after hospital discharge, often in the first six months after leaving the hospital. Some factors that indicate high frequency of sudden death include substantial ventricular myocardial dysfunction [1] and the occurrence of “complex” premature ventricular depolarizations and nonsustained ventricular tachycardia [2–4]. However, the predictive value of these factors alone for sudden death is not sufficiently accurate for clinical usefulness. In patients who have coronary artery disease but no recent myocardial infarction, electrophysiologic stimulation has a high degree of sensitivity [5] for inducing the patient’s clinical arrhythmia, and serial electrophysiologic testing has proven useful for determining the drug therapy that will prevent recurrent arrhythmias [5–8]. Recently, electrophysiologic testing to initiate ventricular tachycardia has been advocated as a technique to identify patients in the postmyocardial infarction period most likely to have sudden cardiac death [9, 10].