LAD纵深型心肌桥形态与CT-FFR的关系研究

p myocardial bridge over LAD and CT-FFR

目的:通过冠状动脉CT血管造影(coronary CT angiography, CCTA)检查探讨左冠状动脉前降支(left anterior descending coronary artery, LAD)纵深型心肌桥(myocardial bridging, MB)形态与CT血流储备分数(CT-FFR)的关系。方法:回顾性分析2018年1月—2022年4月包头医学院第一附属医院影像科323例LAD纵深型MB患者的解剖学信息,并以CT-FFR≤0.80为心肌缺血的指标,将患者分为CT-FFR正常组(237例)及CT-FFR异常组(86例)。采用t检验分析比较2组各MB参数的差异,采用岭回归模型分析CT-FFR值的影响因素,通过ROC曲线分析差异有统计学意义的参数。结果:2组MB入口处位置、出口处位置、长度、肌肉指数、收缩期压迫程度及壁冠状动脉(mural coronary artery, MCA)最狭窄处面积、入口处面积、出口处面积差异均有统计学意义(P<0.05)。岭回归方程显示,MB出口位置、长度及肌肉指数对CT-FFR值具有负向影响(P<0.05),MCA面积对CT-FFR值具有正向影响(P<0.05),并且MB长度、出口位置、肌肉指数对MB心肌缺血均具有较高的诊断价值,三者的曲线下面积(AUC)分别为0.85、0.80、0.79。结论:LAD纵深型MB的位置离冠状窦越近、MCA面积越窄,尤其是MB长度较长的患者,更容易出现心肌缺血的临床表现,应予以高度重视。

Objective To investigate the correlation between the Morphology of deep myocardial bridges(MB)over the left anterior descending coronary artery(LAD)and the measurement of coronary fractional flow reserve derived from CT(CT-FFR)by coronary CT angiography(CCTA).Methods The anatomical information of 323 patients with LAD deep MB in the First Affiliated Hospital of Baotou Medical College from January 2018 to April 2022 were retrospectively analyzed.With CT-FFR≤0.80 as the index for myocardial ischemia,the patients were divided into the normal CT-FFR group(n=237)and the abnormal CT-FFR group(n=86).MB parameters were analyzed and compared between the two groups using the t test.The influencing factors of CT-FFR values were analyzed by a multivariate linear regression model,and the parameters with statistically significant differences were analyzed with the ROC curve.Results Statistically significant differences were found between the two groups in the entrance location,exit location,length,muscle index and systolic compression degree of MB,as well as the areas of the narrowest part,entrance and exit of mural coronary artery(MCA)(P<0.05).The ridge regression equation showed that the exit location,length and muscle index of MB had a negative effect on CT-FFR values(P<0.05),while the area of the MCA had a positive effect on CT-FFR values(P<0.05).Additionally,the length,exit location and muscle index of MB presented high diagnostic values for myocardial ischemia,with the area under the curve(AUC)of 0.85,0.80 and 0.79,respectively.Conclusion The closer the position of LAD deep MB is to the coronary sinus,the narrower the MCA area is,and especially the MB patients with longer MB length are more likely to have clinical manifestations of myocardial ischemia,which should be paid more attention to.