単冠状動脈症の3例

Three cases of single coronary artery

　単冠状動脈症は，先天性冠動脈奇形の中でもまれなものであり，従来比較的予後の良好なminor anomalyと考えられてきた。しかし近年，狭心症^1〜3）・心筋梗塞^4〜6）・心不全^7,8）・不整脈あるいは突然死^9,10）の合併例の報告が重ねられるようになり，本症の臨床的意義が見直されてきている。

　最近，われわれは本症の3例を経験し，このうちの1例にpercutaneous transluminal coronary angioplasty（PTCA）を施行したので，文献的考察を加えて報告する。

Single coronary artery has been considered a minor coronary anomaly without clinical importance. With the wide spread of coronary angiography,however, the disease has been reported to develop complications at a high rate, such as angina, myo-cardial infarction and arrhythmia. We report three patients with single coronary artery with several complications.

Case 1 : A 56-year-old woman having a past his-tory of diabetes mellitus and myocardial infarction was admitted because of the recently developed fre-quent attacks of effort angina. Treadmill test was positive and thallium-201 exercise myocardial scinti-graphy revealed redistribution in the lateral wall. Ascending aortogram suggested that the right coronary artery (RCA) arose from the left sinus of Valsalva. An injection into the right sinus of Val-salva revealed no coronary ostium. Selective left coronary angiogram resulted in the diagnosis of single coronary artery (Smith's type 2) with 90% stenosis in the left circumflex artery (LCX). Left ventriculogram showed hypokinesis in the antero-lateral wall. PTCA performed on this patient re-vealed clinical and nucleomedical improvement.

Case 2 : A 48-year-old man experienced chest pain and syncope. Electrocardiogram revealed ST-eleva-tions in lir , I and aVF, sinus bradycardia and atrio-ventricular junctional rhythm. Angiography resulted in the diagnosis of single coronary artery (Smith's type 2) with 75% stenosis in the RCA. Ergono-vine test was positive.

Case 3: A 69-year-old man complained of chest pain. Electrocardiogram showed complete right bundle branch block, sinus bradycardia and atrio-ventricular junctional rhythm. Cardiac catheteriza-tion revealed that this was also a case of single cor-onary artery (Smith's type 2) with no significant stenosis. Electrophysiological study showed an HV time of 50 msec and atrial overdrive test was nega-tive.

The three cases of Smith's type 2 of single coro-nary artery with several complications were repor-ted.