Serial thallium-201 myocardial imaging after dipyridamole infusion: diagnostic utility in detecting coronary stenoses and relationship to regional wall motion.
After a 4-minute i.v. dipyridamole infusion, 0.14 mg/kg/min, serial thallium-201 scans were obtained in 60 patients undergoing cardiac catheterization. Forty patients had significant (greater than or equal to 50% stenosis) coronary artery disease (CAD), and 20 patients had normal coronary arteries or trivial lesions. The images were graded qualitatively for thallium activity by three observers. Sensitivity was 93% (37 of 40) and specificity was 80% (16 of 20). The sensitivity and specificity of the thallium-201 study were not affected by the extent of CAD, the presence of Q waves, or propranolol therapy. Twenty-seven of 37 patients who had initial defects (73%) had complete thallium redistribution of one or more defects. Patient-by-patient analysis using a regression model of all patients showed that the fate of a segmental thallium defect predicted abnormal wall motion by angiography better than ECG Q waves. The presence of propranolol therapy or collaterals did not significantly affect the thallium redistribution results. We conclude that qualitative interpretation by multiple observers of thallium images after dipyridamole infusion is a highly sensitive and specific test for CAD. After dipyridamole, as with exercise stress, the extent of thallium redistribution is related to the degree of myocardial wall motion abnormality.
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D006328:Cardiac Catheterization; D003251:Constriction, Pathologic; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004176:Dipyridamole / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D011433:Propranolol / Q000494:pharmacology; D011868:Radioisotopes; D011877:Radionuclide Imaging; D013793:Thallium
D011868:Radioisotopes; D004176:Dipyridamole; D011433:Propranolol; D013793:Thallium