Quantitative stress T1-201 myocardial tomography (Bullseye) was evaluated prospectively as compared with coronary angiography in 35 patients with coronary heart disease and 10 normals, and showed a better sensitivity (94%) and specificity (90%) for detecting coronary heart disease. The number of vessels involved was evaluated precisely in 58 of 67 (87%) by Bullseye. The sensitivity and specificity of Bullseye in detecting disease in each coronary artery were 84% and 85% for the left anterior descending artery (LAD), 85% and 100% for left circumflex artery, 93% and 100% for right coronary artery. 85% of one vessel disease, 83% of two-vessel disease and 80% of three-vessel disease were recognized by Bullseye. The sensitivity of Bullseye in detecting coronary heart disease was related to the extent of coronary stenosis. The more severe the coronary stenosis is, the higher is the Bullseye's sensitivity. In detecting diseased vessels, 38% of patients with mild coronary stenosis had positive Bullseye, however, 98% of patients with severe coronary stenosis had positive Bullseye. For localization of myocardial infarction in posterior lateral wall, posterior wall and posterior septum. Bullseye is more sensitive than ECG. Thus, quantitative stress T1-201 myocardial tomography provides high diagnostic accuracy for the detection and localization of coronary heart disease.