Noninvasive detection of regional myocardial perfusion abnormality with 201Tl and 81Rb

Myocardial scintigrams were performed at rest and during exercise using 201Tl and 81Rb. Patients underwent graded ergometer exercise stress tests. In normals, myocardial images were horse-shoe of O-shaped and concentration of radionuclide was relatively uniform throughout the myocardium. In 13 patients with old myocardial infarctions, and abnormal Q waves, regional myocardial perfusion defects (cold area) were detected. Their locations correlated with sites of the abnormal Q waves. Two patients had no abnormal Q waves at the examination, but their scintigrams showed cold areas, the locations of which coincided with coronary angiographic findings. Exercise stress Ecg and stress scintigrams were performed. Myocardial perfusion defects, which developed from exercise stress, were detected in 9 of 10 positive exercise Ecg patients, 2 of 4 equivocal exercise Ecg patients, and 2 of 10 negative exercise Ecg patients. These 2 patients (exercise Ecg (-), stress scintigram (+)) had typical angina. Findings of exercise stress scintigrams coincided better with clinical findings than did those of exercise Ecg. These scintigraphic methods appear to be excellent for detection of noninvasive coronary heart disease noninvasively. (Evans, J.)