64层螺旋CT冠状动脉成像对心肌桥-壁冠状动脉的评价

目的 探讨心肌桥-壁冠状动脉(MB-MCA)形态学特征及其与冠状动脉粥样硬化病变关系.方法 回顾性分析6729例可疑或确诊冠心病(CHD)患者64层螺旋CT冠状动脉血管成像(CTA)结果,由2位心血管CT诊断医师独立判断MB-MCA的存在,结果一致时诊断为MB-MCA.测量MB厚度、MCA长度及管径,记录MB-MCA位置、包绕情况、MCA两端成角情况,并记录MCA本身以及其近、远段冠状动脉粥样硬化病变情况,应用卡方检验,分析心肌桥近段、远段冠状动脉及壁冠状动脉自身动脉粥样硬化病变发生率有无差异.结果 6729例患者中发现MB-MCA总计1214例(18.0%),1262处.MB-MCA位于LAD者占90.7%(1145例).MSCT显示MCA可被心肌完全包绕(39.3%,496/1262)或不完全包绕(60.7%,766/1262).MCA长度为(18.6±9.0) mm.MB厚度为(2.2±1.7) mm.77.3%的MCA近端或(和)远端成角.MB-MCA近段和远段冠状动脉粥样硬化病变发生率分别为53.3%和2.3%,MCA本身粥样硬化病变发生率为0.5%,各组间有显著的统计学差异(P＜0.05).结论 64层螺旋CT能够清楚显示载MB-MCA冠状动脉全程和MB-MCA本身,并用于评价MB-MCA形态学特征.心肌桥近段冠状动脉易发生粥样硬化病变.

Evaluation of myocardial bridge-mural coronary artery by 64 slices CT in coronary artery angiography

Objective To evaluate the morphological characteristics of myocardial bridge-mural coronary artery (MB-MCA) and investigate the relationship between MB-MCA and the coronary atherosclerosis. Methods The images of 6729 patients with suspected or documented coronary artery disease who underwent 64-MSCT were analyzed retrospectively by 2 cardiovascular radiologists. When consistency was obtained by the independent interpretations, the diagnosis of MB-MCA could be confirmed. The length and diameter of MCA and thickness of MB were measured, and situation of MB, encasement form of MCA, adjacent vessel morphology and the distribution of atherosclerosis were observed. Results Among 6729 patients, 1262 sites of MB-MCA were detected in 1214 (18.0%) cases. 1145 (90.7%) MB-MCA were located on the LAD. MCA could be encased partially by MB (60.7%, 766/1262) or covered completely (39.3%, 496/1262). The length of MCA was (18.6±9.0) mm. The thickness of MB was (2.2±1.7) mm. The proximal and/or distal segments to the MB-MCA showed tortuous in 77.3% of the cases. The overall prevalence of coronary atherosclerosis of the proximal segment of MB-MCA was 53.3%, whereas the coronary artery atherosclerosis of MCA itself and the distal segment was 0.5% and 2.3%, respectively, which demonstrated significant difference. Conclusion 64-MSCT can clearly detect the entire running course of coronary arteries and MB-MCA, which provide an accurate demonstration of the anatomical characteristics of MB-MCA. MB-MCA predisposes to the development of atherosclerosis in the coronary artery segment proximal to the bridge.