The study examined the value of rest and exercise radionuclide ventriculography in risk stratification in patients with suspected coronary artery disease. There were 604 patients, 474 men and 130 women, aged 55 ± 11 years (mean ± standard deviation). At a follow-up of 18 ± 10 months, there were 43 hard cardiac events: 27 patients died of cardiac causes and 16 had nonfatal acute myocardial infarctions. Univariate and multivariate survival analysis of the 10 most important clinical and exercise variables identified the exercise left ventricular ejection fraction as the most important predictor of death and total cardiac events (χ2 = 18.1 and 29.6, respectively). The exercise heart rate was a significant, independent, but much weaker predictor of cardiac death and total events (χ2 = 8.4 and 3.9, respectively), while exercise tolerance was a significant independent predictor of cardiac death only (χ2 = 6.4). Actuarial life table analysis showed that the risk for future cardiac events increased in stepwise fashion as the exercise ejection fraction decreased. Thus, the exercise left ventricular ejection fraction is a useful prognosticator in patients with suspected coronary artery disease. This finding has important implications in patient management. © 1985.