Thallium-201 scintigraphy in unstable angina pectoris.

Abstract

The 201Tl scintigraphy was performed during the pain free period in 98 patients with unstable angina. Scintiscans were positive in 39 patients, questionable in 27 patients and normal in 32 patients. Patients (81) responded favorably to treatment (group I). Patients (17) had complicated courses (group II) and, despite maximal treatment with propranolol, either developed infarction (6 patients) or continued to have angina necessitating coronary surgery (11 patients). In group I during the pain free period 26 of 81 patients had positive 201Tl scans; 20 patients had an abnormal ECG at that time; during angina 18 patients had transient ECG changes. In group II during the pain free period 13 of 17 patients had positive scans; 2 patients had abnormal ECG at that time; during angina 12 patients showed transient ECG changes. The sensitivity to recognize group II was 76% for 201Tl scintigraphy, 11% for ECG during the pain free period; 70% for ECG during angina; 94% for the combination of either positive scans or abnormal ECG. Positive 201Tl scans occur in patients with unstable angina, positive scans can be obtained during the pain free period and 201Tl scans are more frequently positive in patients with complicated course.