双源CT对心肌桥与冠状动脉粥样硬化关系的探讨

Correlation Between Myocardial Bridge and Coronary Atherosclerotic Plaque: Analyze with Dual-Source CT

目的利用双源CT(DSCT)探讨左冠状动脉前降支心肌桥(myocardial bridging,MB)与该支冠状动脉粥样硬化的相关关系。方法采用DSCT对500例可疑冠心病(coronary artery disease,CHD)和体检者行冠状动脉CT血管成像(CTA),由3位CT诊断医师独立判断并在结果一致时确定前降支MB,测量MB长度、厚度。将所有病例分为前降支MB组和非MB组,利用多平面重组(MPR)、最大密度投影(MIP)、曲面重组(CPR)、容积再现(VR)等后处理技术联合观察前降支钙化及粥样硬化斑块的发生率,利用Circulation软件QCA工具测量前降支由于斑块所致的狭窄率,比较MB组与非MB组的平均狭窄程度以及钙化、粥样硬化斑块的发生率。应用Spearman等级相关统计分析MB近端冠状动脉狭窄程度与MB的长度及厚度之间的相关关系。结果 500例受检者中冠状动脉CTA发现前降支MB 135例(27%)。MB组钙化及粥样硬化斑块的发生率分别为38.5%和53.3%,非MB组钙化及粥样硬化斑块的发生率分别为32.3%和46.3%,MB组与非MB组的平均狭窄程度分别为(45.6±21.2)%和(45.7±22.2)%,两组之间钙化的发生率、粥样硬化斑块的发生率及平均狭窄程度差异均无明显统计学意义(P=0.25;P=0.16;P=0.99),MB近端冠状动脉狭窄程度与MB的长度及厚度间相关性均不明显(r=-0.03,P=0.83;r=-0.10,P=0.42)。结论左冠状动脉前降支MB的存在并没有显著增加该支冠状动脉狭窄程度及粥样硬化斑块的总体发生率,MB近端冠状动脉狭窄程度与MB的长度及厚度相关性不明显。

Objective To investigate the correlation between myocardial bridge and coronary atherosclerotic plaque of the left coronary anterior descending branches using dual source computed tomography（DSCT）.Methods A total of 500 patients suspected with coronary artery disease（CHD） underwent dual source computed tomography coronary angiography（DSCTCA） examination.Three radiologists analyzed the images independently and consistency diagnosis of MB was made.The length and depth of MB were measured.All the cases were divided to two groups,left coronary anterior descending branches with MB and without MB.The left coronary anterior descending branches were observed on MPR,MIP,CPR,VR images.The stenosis degree proximal to MB due to the atherosclerotic plaque were calculated with QCA method.The detection rate of the calcium and atherosclerotic plaque between the two groups were compared respectively.Spearman correlation analysis was used to analyze the relation between the length,depth of MB and degree of stenosis proximal to MB.Results A total of 135 sites of MB in anterior descending branch were found.The detection rate of the calcium and atherosclerotic plaque were 38.5% and 53.3% in the MB group,and 32.3% and 46.3% in the non-MB group.The mean stenosis degree of the two group were（45.6±21.2）% and（45.7±22.2）%.There were no statistical differences of the detection rate of the calcium,atherosclerotic plaque and the mean stenosis degree between two groups（P=0.25;P=0.16;P=0.99）.No significant correlation was found between the length,depth of MB and degree of stenosis proximal to the myocardial bridge.Conclusion The myocardial bridges of the left coronary anterior descending branch arteries do not increase the mean stenosis degree and global detection rate of the atherosclerotic plaque.There are no significant correlation between the degree of stenosis proximal to the myocardial bridge and length,depth of the myocardial bridge.