Assessment of early ventricular systole by first pass radionuclide angiography: useful method for detection of left ventricular dysfunction at rest in patients with coronary artery disease.

To identify abnormal left ventricular function without exercise stress in patients with coronary artery disease first-pass radionuclide angiograms were analyzed in 32 normal subjects (Group I); 31 patients with coronary disease and normal contrast ventriculograms (Group II); and 17 patients with coronary disease and depressed left ventricular function (Group III). Total ejection fraction (EF) was computed with standard angiographic methods and from each time-activity curve. During the first third of systole, ejection fraction was determined manually by averaging three to five beats and the value compared with that obtained with contrast ventriculography: (Formula: see text). Both total radionuclide ejection fraction (r = 0.95) and first-third ejection fraction (r = 0.91) correlated well with angiography. Intraobserver and interobserver variation was small, averaging 0.02 +/- 0.02 (range 0 to 0.05). The radionuclide first-third ejection fraction was 0.25 or greater in normal subjects and less than 0.25 in 29 of 31 patients (94 percent) in Group II and in all patients in Group III. It is concluded that the first-third ejection fraction obtained with first pass angiography identifies subtle abnormalities of left ventricular function at rest in more than 90 percent of patients with coronary disease that may not be recognized by total ejection fraction alone.