摘要目的 对比评价不完全与完全心肌桥-壁冠状动脉(MB-MCA)的CT影像学特征.方法 回顾性分析50例显示有MB患者的双源CT冠状动脉血管成像(DSCTA)资料,将其分为不完全MB-MCA组(MCA被心肌部分包绕,至少在1/2以上)和完全MB-MCA组(MCA完全被心肌包绕),分别在其最佳收缩期及舒张期测量MCA及其近远侧血管的管径变化,计算MCA狭窄率,并记录MB近侧血管发生粥样硬化情况.结果 50例患者中,DSCTA显示58处MB,平均长度为(2.02±1.02)cm,其中不完全MB 23处,完全MB 35处,前降支中段32处(55.2%),前降支远段17处(29.3%),前降支近段1处,第一对角支3处,钝缘支4处,右冠状动脉远段1处.不完全MB-MCA舒张期及收缩期管径、狭窄率分别为(1.93±0.49)mm、(1.71±0.45)mm和25.21%±21.02%,完全MB-MCA舒张期及收缩期管径、狭窄率分别为(2.21±0.41)mm、(1.63±0.52)mm和10.38%±20.2%.两型MB-MCA管径变化(t=2.76,P=0.008)及MCA狭窄率(t=2.667,P=0.01)差异有统计学意义.8处(34.78%)不完全MB及15处(42.86%)完全MB近侧血管发生粥样硬化,两者之间差异无统计学意义(x2=0.378,P＞0.05).结论 DSCTA能够清晰的显示不完全和完全MB,并能准确评价MB-MCA在舒张期和收缩期的形态学变化及MB近侧血管发生粥样硬化的情况.

abstractsObjective To evaluate the CT imaging characteristics of incomplete and complete myocardial bridges-mural coronary artery(MB-MCA). Methods Fifty subjects with dual source coronary CT angiography(DSCTA)evidenced MB were included. The subjects were divided into incomplete MBMCA and complete MB-MCA groups. The diameter of MCA in best systole phase and diastole phase, the MCA stenosis rate, the presence of atheromatous change proximal to the MB were evaluated. Results There were 58 MB, the average length was(2. 02 ± 1.02)cm, 23 were incomplete MB and 35 were complete MB.Thirty-two MB were in the middle segments of left anterior descending artery(55.2%);17 MB were in the distal segment of the left anterior descending artery(29. 3%);1 MB was in the proximal segment of left anterior descending artery;3 MB in diagonal branch;4 MB in obtuse marginal branch, 1 MB in distal right coronary artery. It was statistically significant difference between the incomplete MB-MCA and the complete MB-MCA of the diameter change in diastole and systole phase[(1.93 ±0. 49)mm,(1.71 ±0. 45)mm vs.(2.21 ±0.41)mm,(1.63 ±0.52)mm, P=0.008]and stenosis rate(10.38%±20.2%vs. 25.12% ±21.02%, P = 0. 01). Atherosclerotic finding was evidenced in 8 incomplete MB(34. 78%)and 15complete MB(42. 86%)at the proximal vessel of mural coronary artery(P ＞ 0. 05). Conclusion DSCTA can vividly display the incomplete and complete myocardial MB, accurately evaluate the shape change of MB-MCA in diastole and systole phase and detect the atherosclerotic change in the proximal vessel of MB.