目的：探讨双源CT（DSCT）冠状动脉造影对心肌桥-壁冠状动脉（MB-MCA）的检出率及其形态学特征。材料与方法：应用DSCT对470例患者行冠状动脉造影，测量MB的长度、厚度及MCA受压缩程度，用均数±标准差表示；观察记录MCA近段、远段邻近血管及MCA本身的形态变化。用Pearson等级相关检验、Wilcoxon秩和检验作统计学分析。结果：①MB-MCA检出率为27.9%（131/470），MB平均长度为（20.8±9.0）mm，MB的平均厚度为（2.3±1.1）mm，MCA平均受压缩程度为（37.8±16.9）%；MCA受压缩程度与MB厚度呈正相关（r=0.60，P=0.000），与MB的长度无相关性（r=0.21，P=0.540）。MB的厚度与MCA长度无相关性（r=0.18，P=0.101）。②62.7%（82例）MB-MCA桥前段或/和桥后段血管走行迂曲成角，且与MB的厚度相关（z=-3.15，P=0.002），而与MB的长度无相关性（z=-0.41，P=0.967）。③67例MCA在收缩期呈圆锥状改变，舒张期这种改变明显减轻或消失。经统计学分析，MCA的这一表现与MB的厚度、长度均有相关性（z=-2.91，P＝0.004；z=-2.61，P＝0.009）。④46例MCA相邻的血管有动脉硬化征象，经统计学分析，MCA相邻血管有动脉硬化征象组与MB的厚度、长度均有相关性（z=-3.42，P＝0.001；z= -2.89，P＝0.004）。结论：DSCT可正确诊断MB-MCA的存在，并可判断MB-MCA的形态特征，为临床诊断和治疗提供了丰富的有价值的信息。

Objective: To investigate the depiction rate and morphologic features of myocardial bridge and mural coronary artery(MB-MCA) with dual-source CT(DSCT) coronary angiography. Materials and Methods: Four hundred and seventy cases of patients underwent DSCT coronary angiography. The length and thickness of MB, the degree of systolic compression of MCA were measured expressed with the means±standard deviations. The situation of the MCA and the nearby arteries of MB-MCA were observed and recorded. Statistical analysis were performed with Pearson correlation analysis and the Wilcoxon two-sample test. Results: ①MB-MCA was detected with DSCT in 131(27.9%) of 470 patients. Mean MB length and depth at DSCT were (20.8±9.0)mm and (2.3±1.1)mm, respectively. The degree of systolic compression was (37.8±16.9)%. A significant correlation was not found between systolic compression and length(r=0.17, P=0.540) but was found with depth(r=0.60, P=0.000). A significant correlation was not found between depth and length(r=0.18, P=0.101). ②62.7%(82 cases) of the arteries proximal or/and distal to the MB-MCA were tortuous. A significant correlation was found between tortuous degree and the depth of MB(z=-3.15, P=0.002). ③The MCA had cone-shaped change in systole and significantly reduced or disappeared in diastole in 67 cases. These features had significant correlation with depth and length of MB(z=-2.91, P＝0.004; z=-2.61, P＝0.009). ④Arteriosclerotic signs in 46 cases were found in neighboring arteries of the MCA. The depth and the length of MB were related to the arteriosclerosis(z=-3.42, P＝0.001; z=-2.89, P＝0.004). Conclusion: DSCT may diagnose correctly the presence and may judge the morphological characteristic of MB-MCA, which can provide more worthy information for clinical diagnosis and treatment.