Myocardial scintigraphy with 99mTc-pyrophosphate in 150 coronary care unit patients

150 patients, admitted to the coronary care unit with suspicion of acute myocardial infarction, received pyrophosphate labelled with 99mTc, 6-120 h after onset of symptoms, mean 24 h, and were examined in the anterior posterior position and in the left anterior oblique position with a mobile gamma camera. Scintigrams were obtained initially at the injection, and then every 15th min during 1h. The scintigrams were evaluated with regard to presence and localization of radionuclide uptake in myocardial area. In 98 patients with a clinical diagnosis of acute myocardial infarction, uptake was found in 95, with good correlation between ECG and scintigraphic localization. 2. patients with myocardial infarction, verified at autopsy, did not show any uptake and 1 patient, surviving the myocardial infarction, also showed negative result. 19 of 26 patients with unstable angina pectoris also exhibited an uptake in the myocardium. 25 of 26 patients with other diagnoses showed no uptake, while in 1 patient an uptake was recorded. It is concluded that with 99mTc-pyrophosphate scintigraphy it is possible to separate ischemic heart disease from other diseases in patients with chest pain.