Usefulness of dual energy SPECT and Bull's eye display with technetium-99m pyrophosphate and thallium-201 for patients with acute myocardial infarction

Dual energy single photon emission computed tomography (SPECT) was performed by injecting iv both Tc-99m pyrophosphate (20 mCi) and Tl-201 chloride (3 mCi) 3 hours and 5 minutes before scanning, respectively, in 17 patients with acute myocardial infarction. Overlap images of the two radionuclides were represented by Bull's eye display. The Bull's eye display allowed easy detection of infarcted site and differentiation of acute from old infarcted myocardium. It was also useful for the follow-up of infarcted site to prevent subsequent infarction. When both Tc-99m pyrophosphate and Tl-201 chloride were overlapped to larger extent, left ventricular wall motion abnormality during chronic stage was milder. The present method has the potential for providing more accurate information about acute myocardial infarction. (N.K.)