前降支心肌桥与桥前段冠状动脉粥样硬化狭窄的相关性

Association of Myocardial Bridge of the Left Anterior Descending Coronary Artery with Coronary Atherosclerotic Stenosis in the Segment Proximal to the Site of Bridge

目的探讨前降支心肌桥与心肌桥前段冠状动脉粥样硬化狭窄的相关性，以确定前降支心肌桥是否与心肌桥前段冠状动脉粥样硬化狭窄的发生存在独立的关联。方法回顾性分析2011年3月至2012年12月9862例拟诊为冠心病患者的CT冠状动脉血管成像资料（只记录并分别按照前降支有无冠脉粥样硬化及有无心肌桥进行分组）及临床资料（包括年龄、性别、吸烟情况、有无家族心脏病史、糖尿病、高血压、高脂血症、体重指数、静息心率），应用Logistic回归模型分析发生于前降支心肌桥与桥前段冠状动脉粥样硬化狭窄的关系。结果9862例患者中3359例患者前降支存在50％以上狭窄，前降支心肌桥为3182（32．3％）例，心肌桥平均长度为（17．3±5．2）mm，覆盖的心肌平均厚度为（1．2±0．9）mm。前降支动脉硬化狭窄组含有心肌桥1658例，前降支无动脉硬化狭窄组含有心肌桥1524例，两组比较差异具有统计学意义（χ^2=681．12，P〈0．05），Logistic回归表明心肌桥的DR值为3．07，95％置信区间2．81—3．37（P〈0．001），最终经过年龄、性别、吸烟情况、家族心脏病史、高血压、高脂血症、体重指数、糖尿病、静息心率等因素校正后，OR值为2．86，95％置信区间2．60～3．16（P〈0．001）。结论前降支心肌桥与心肌桥前段冠状动脉粥样硬化狭窄的发生存在独立的相关性。

Objective To investigate whether myocardial bridging （MB） is independently associated with coronary atherosclerosis proximal to MB in the left anterior descending coronary artery （LAD） identified by computed tomographic coronary angiography （CCTA） . Methods From March 2011 to December 2012, patients （n = 9 862） with suspected coronary disease underwent CCTA using dual-source CT scanner. The baseline clinical characteristics （ age, gender, smoking history, presence of hypertension, dyslipidemia, diabetes mellitus, family history of heart attack, and body mass index） and the results of CCTA were reviewed. Two ra- diologists evaluated the coronary artery for MB and coronary atherosclerosis stenosis （CAS） in LAD and made a diagnosis by consensus. Significant independent risk factors for CAS were investigated by multivariate logistic re- gression analysis. Results A total of 3 182 （32. 3 % ） cases of MB and 3 359 cases of CAS of LAD were identified. No patient with CAS in the tunneled segment was found. The mean length of bridges and the mean thickness of the overlying myocardium was （ 17.3 ±5.2） mm and （ 1.2 ±0. 9） mm, respectively. There were 1658 MB cases in 3 359 cases of LAD stenosis and 1 524 MB cases in 6 503 cases of no LAD stenosis （X2 = 681.12, P 〈 0. 05）. Logistic regression analysis showed that MB in the LAD were significantly associated with CAS in the proximal LAD （ OR = 3.07, 95% CI = 2. 81-3.37, P 〈 0. 001 ）, and after final adjustment for age, gender, body mass index, family history of heart attack, smoking, hypertension, dyslipidemia, diabetes mellitus, and resting heart rate （ OR = 2.86, 95% CI = 2. 60-3.16, P 〈 0. 001 ）. Conclusion MB in the LAD is inde- pendently associated with CAS in the proximal segment to MB.