Utilizing a dynamic radionuclide method, the right and left ventricular ejection fractions were measured in 96 men with arteriographically defined coronary arterial disease and in 14 normal subjects. The radionuclidically estimated right ventricular ejection fraction (RVEF) correlated with the RVEF measured with biplane cineventriculographic studies (r = 0.80; n = 43), and the left ventricular ejection fraction (LVEF) measured from radionuclide data have been shown to correlate with the LVEF from single-plane cineventriculographic studies (r = 0.89; n = 60). The mean normal RVEF was 0.57 +/- 0.01 (SE) (range, 0.51 to 0.64), and the mean normal LVEF was 0.66 +/- 0.01 (range, 0.57 to 0.74). The LVEF was decreased in the men with coronary arterial disease and isolated obstruction of the left anterior descending coronary artery, double-vessel disease, and triple-vessel disease, but was normal in those with isolated right coronary disease. The RVEF was normal in each of these groups, except those with triple-vessel disease. Myocardial infarction was associated with impairment of LVEF, although some patients without myocardial infarction had depressed LVEF. The RVEF was preserved in patients with infarction, except those with multiple myocardial infarctions. Thus, impaired LVEF in coronary arterial disease is associated with myocardial infarction, and RVEF is relatively preserved except in multiple-vessel disease and myocardial infarction and in association with impaired LVEF.