大山 恭夫

Yasuo OHYAMA

横浜市立大学第2内科

Second Department of Internal Medicine Yokohama City University Hospital

キーワード : Myocardial contrast echocardiography, Overlap area, Chest pain syndrome, Old myocardial infarction

To assess the overlapping of myocardial areas of the left ventricle (LV), which were per fused by the right or left coronary artery, we performed myocardial contrast echocardiography using 5% sonicated human albumin as a contrast dye for intracoronary injection. The subjects were 15 patients with chest pain syndrome in whom no significantly stenotic changes in coronary arteries had been observed on angiography and 10 with old myocardial infarction in whom significant coronary artery stenosis and well developed collateral vessels had been angiographically verified. Echocardiographic mapping was performed using a MIPRON system; the LV wall at a pappillary muscle level on the short axis view was automatically divided into 16 segments, and then each segment was divided into 4 zones from the endocardium to epicardium. When the averaged intensity of echo contrast of the two central zones of a segment increased by 25% or more (positive stain) after injection the contrast dye into a coronary artery, the segment was considered to be per fused by the artery. The area of the LV wall perfused by the right or left coronary artery was expressed by dividing the number of segments with positive stain by 16 and indicated by percent. LV wall areas perfused by the right coronary artery were significantly greater in patients with anteroseptal infarction than in patients with chest pain syndrome or those with inferior infarction, while LV areas perfused by the left coronary artery were significantly smaller in the patients with anteroseptal infarction than in the two other groups. The areas which were perfused by both coronary arteries were significantly greater in the patients with anteroseptal or inferior infarction than in those with chest pain syndrome [21.6±15.7 (SD)% in patients with anteroseptal infarction, 18.0±6.8% in those inferior infarction and 12.2±2.3% in those with chest pain syndrome (p