METHODS: This cross-sectional study included two hundred and twenty-seven patients (age 53.2 [11.1] years, 48 % female) who underwent 640-slice CCTA and were diagnosed with MB. MB severity was measured as MB muscle index (MMI) (MB length x MB thickness) and, left ventricular hypertrophy (LVH) was assessed with transthoracic echocardiography.
RESULTS: MB segments were detected in all patients on the left anterior descending artery. CCTA was performed to exclude coronary artery disease in most patients (90%, n=206). Eighty-two (36.1 %) had LVH, and MMI was significantly higher in patients with LVH than those without LVH (27.3[19.5-38.9] vs 24 [13.8-37.1], P = 0.022, respectively). There was a positive correlation between the left ventricular mass index and myocardial bridge length (r=0.414, P =0.001), MB index (r=0.310, P <0.001), and the age of the patients (r=0.191, P = 0.004). MB thickness and MMI were also positively correlated with relative wall thickness.
CONCLUSIONS: MB is a common finding, and its severity is associated with left ventricular hypertrophy in patients undergoing CCTA.
方法:这项横断面研究包括27名患者(年龄53.2[11.1]岁,48%的女性)接受了640片CCTA并被诊断为MB。MB严重程度以MB肌肉指数(MMI)(MB长度xMB厚度)和,经胸超声心动图评估左心室肥厚(LVH)。
结果:在所有患者的左前降支动脉中均检测到MB段。在大多数患者中进行CCTA以排除冠状动脉疾病(90%,n=206)。82例(36.1%)有LVH,LVH患者的MMI明显高于无LVH患者(27.3[19.5-38.9]vs24[13.8-37.1],分别为P=0.022)。左心室质量指数与心肌桥长度呈正相关(r=0.414,P=0.001)。MB指数(r=0.310,P<0.001),患者年龄(r=0.191,P=0.004)。MB厚度和MMI也与相对壁厚呈正相关。
结论:MB是一个常见的发现,其严重程度与接受CCTA的患者左心室肥厚有关。