Clinical outcome of silent myocardial ischemia

Abstract

Asymptomatic coronary artery disease can be detected by an abnormal electrocardiogram at rest, by a positive exercise test result unaccompanied by pain, or by the demonstration of silent ischemic episodes during daily activities. However, the clinical outcome of patients with silent myocardial ischemia has not yet been clearly defined. In a study of 356 patients with documented coronary disease--211 of whom had previous myocardial infarction--the prognostic information of spontaneous ST-segment depression was found to be independent of that associated with a positive exercise test result, ejection fraction, and extent of arteriographically documented coronary artery disease. Patients with asymptomatic ischemia had a higher coronary event rate than those without ischemia. Cardiac event rates followed a similar pattern for patients with silent, symptomatic and mixed ischemia--whether or not there was previous myocardial infarction.