Automatic determination of the site of myocardial infarction and coronary perfusion territory with SPECT

In order to estimate coronary perfusion territory in terms of the extent of myocardial infarction, we developed a diagnostic program for perfusion territory from the territory map of each major coronary artery. We studied 30 patients with myocardial infarction: 16 patients with LAD lesion, 6 patients with LCX lesion, and 8 patients with RCA lesion. We constructed the infarction map from circumferential profile curves of 10 short axis sections of SPECT in each patient. The resultant infarct area corresponding to each of LAD, LCX and RCA lesions was used as the mean of infarct size in typical cases, and the perfusion territory map was constructed for three major coronary arteries. The infarct index based on the territory map was calculated and used for automatic determination of coronary perfusion territory. With LAD lesions, we further studied if the lesion was proximal or distal to the first diagonal branch of LAD artery. We conclude that this diagnostic program is quite useful in automatic estimation of coronary artery lesion which caused myocardial infarction, and that the lesion proximal or distal to the first diagonal branch results in whether lateral wall infarct is involved or not. (author)