Munakata K, Sato N, Sasaki Y, Yasutake M, Kusama Y, Takayama M, Kishida H, Hayakawa H
First Department of Internal Medicine, Nippon Medical School, Tokyo, Japan.
Jpn Circ J. 1992 Dec;56(12):1248-52. doi: 10.1253/jcj.56.1248.
Myocardial bridge (MB) is a congenital anomaly of the coronary artery and may occur in 5 to 12% of the human population. However, the mechanism of MB-induced myocardial ischemia is still speculative. We report 2 cases of variant form angina pectoris associated with MB in which myocardial ischemia seemed to be related to the interaction between coronary perfusion and MB. In case 1, electrocardiography during anginal attack at rest showed ST elevation in the inferior leads and MB was observed after percutaneous transluminal coronary angioplasty at the site of the right coronary artery lesion following successful dilatation. In case 2, MB of the left anterior descending coronary was located in the identical portion where coronary vasospasm was induced by intracoronary acetylcholine injection, although ischemia during the spontaneous anginal attack was limited to the inferior area of myocardium. These 2 cases suggest that MB can be, at least in some patients, one of the possible causes of the endothelial damage which seems to be related to coronary vasospasm; this was documented in both cases.
心肌桥（MB）是一种冠状动脉的先天性异常，在人群中的发生率约为5%至12%。然而，MB导致心肌缺血的机制仍具有推测性。我们报告2例与MB相关的变异型心绞痛病例，其中心肌缺血似乎与冠状动脉灌注和MB之间的相互作用有关。病例1中，静息性心绞痛发作时心电图显示下壁导联ST段抬高，经皮冠状动脉腔内血管成形术成功扩张右冠状动脉病变部位后观察到MB。病例2中，左前降支冠状动脉的MB位于冠状动脉内注射乙酰胆碱诱发冠状动脉痉挛的相同部位，尽管自发性心绞痛发作时的缺血仅限于心肌下壁区域。这2例病例表明，至少在部分患者中，MB可能是与冠状动脉痉挛相关的内皮损伤的可能原因之一；这在两例病例中均得到证实。
