Left ventricular performance in unstable angina: assessment with radionuclide techniques.
In a clinical trial we studied left ventricular performance at rest in 50 patients with unstable angina by radionuclide techniques. Thallium-201 scintigraphy was performed on admission in 38 patients and repeated after 48 hr in 32 patients. Also dynamic blood pool scintigraphy was performed in 37 patients on admission and in 45 patients after 48 hr. Of the 50 patients, 27 (54%) had no recurrent episodes of myocardial ischemia, but 23 (46%) patients showed recurrent ischemic episodes of whom 11 (22%) patients developed a myocardial infarction. The thallium-201 images showed perfusion defects in 27 (71%) of the 38 patients studied on admission and in 20 (63%) of the 32 patients studied at 48 hr. No relation between clinical outcome and presence or absence of defects was observed. Left ventricular ejection fraction was abnormal (less than 50%) in 19 (51%) of the 37 patients on admission and in 29 (64%) of the 45 patients studied at 48 hr. As with thallium-201, no relation could be established between clinical outcome and left ventricular ejection fraction. It is concluded that radionuclide techniques are useful to provide insight into the pathophysiological mechanism of unstable angina, but they are not helpful for the short-time assessment of clinical outcome.
D000787:Angina Pectoris / Q000000981:diagnostic imaging*; D000789:Angina, Unstable / Q000000981:diagnostic imaging* / Q000188:drug therapy; D002986:Clinical Trials as Topic; D017023:Coronary Angiography; D003327:Coronary Disease / Q000000981:diagnostic imaging; D004311:Double-Blind Method; D004562:Electrocardiography; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008790:Metoprolol / Q000627:therapeutic use; D008875:Middle Aged; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000000981:diagnostic imaging; D009543:Nifedipine / Q000627:therapeutic use; D011868:Radioisotopes; D011877:Radionuclide Imaging; D013318:Stroke Volume; D013793:Thallium
D011868:Radioisotopes; D013793:Thallium; D008790:Metoprolol; D009543:Nifedipine