Comparison of exercise radionuclide angiocardiography and thallium-201 myocardial perfusion imaging in coronary artery disease

First pass radionuclide angiocardiography and thallium-201 myocardial perfusion imaging were performed at rest and during exercise in 48 patients with chest pain: 39 with angiographically documented coronary artery disease and 9 with normal coronary arteries. Maximal graded upright bicycle exercise was used for both studies to assure identical exercise conditions. All nine patients without coronary artery disease had normal exercise thallium images, normal exercise regional wall motion and at least a 5 percent absolute increase in left ventricular ejection fraction during exercise (normal exercise left ventricular reserve). Ischemic S-T segment depression was demonstrated in 17 (44 percent) of the 39 patients with coronary artery disease. Findings on the two exercise tests were concordant in all cases. New or augmented thallium perfusion defects were detected in 24 (62 percent) of the 39 patients, whereas abnormal exercise left ventricular reserve was present in 33 (85 percent) (p <0.05). There was a close concordance between exercise-induced perfusion defects and regional wall motion abnormalities. The magnitude of change in ejection fraction from rest to exercise was significantly greater in patients with an abnormal exercise thallium study than in those with a normal study (−8 ± 2 percent versus −1 ± 1 percent, p <0.05). Both radionuclide studies were abnormal In 21 (54 percent) of the 39 patients, whereas both were normal only in 3 patients, all of whom had single vessel disease. Abnormal exercise left ventricular reserve was present in 12 patients with normal exercise thallium studies.