RELATIONSHIP BETWEEN INSUFFICIENT REDISTRIBUTION IN EXERCISE TL-201 MYOCARDIAL SINGLE-PHOTON EMISSION COMPUTED-TOMOGRAPHY AND REVERSE REDISTRIBUTION AT REST

It is widely accepted that perfusion defects in 3 to 4-h delayed image s in exercise thallium-201 (Tl-201) myocardial scintigraphy underestim ate the viability of myocardium in the infarct region. In the present study, to examine the contribution of the condition of myocardium whic h demonstrates reverse redistribution in resting scintigraphy to the i nsufficiency of redistribution in the 4-h delayed image in exercise sc intigraphy, we performed exercise and resting Tl-201 myocardial single -photon emission computed tomography in 58 patients with acute myocard ial infarction and a single diseased coronary artery. Twenty eight pat ients demonstrated reverse redistribution (group RR) and 28 showed a f ixed defect (group FD) in resting scintigraphy. Redistribution in the 4-h delayed image in exercise scintigraphy was significantly more insu fficient in group RR than in group FD (p<0.01), and the degree of the insufficiency of redistribution in exercise scintigraphy closely corre lated with the degree of reverse redistribution in resting scintigraph y (r=0.79, p<0.001). We conclude that in patients with acute myocardia l infarction, the condition of myocardium which demonstrates reverse r edistribution in resting myocardial scintigraphy is related to the ins ufficiency of redistribution in the delayed image in exercise scintigr aphy.