Abstract：
BACKGROUND: Myocardial bridging (MB) was considered a congenital anomaly and found increased frequency in coronary computed tomography angiography. Some case studies reported the association of MB with various cardiomyopathies. However, the association between MB severity and left ventricular hypertrophy remains unclear. This cross-sectional study aimed to evaluate whether myocardial bridge is related to left ventricular hypertrophy in patients referred for coronary computed tomography angiography (CCTA).
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.
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.
摘要：
背景：心肌桥（MB）被认为是先天性异常，在冠状动脉计算机断层扫描血管造影术中发现频率增加。一些案例研究报道了MB与各种心肌病的关联。然而,MB严重程度与左心室肥厚之间的关联尚不清楚.这项横断面研究旨在评估接受冠状动脉计算机断层扫描血管造影（CCTA）的患者的心肌桥是否与左心室肥厚有关。
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。
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。
