心肌桥和壁冠状动脉的多层螺旋CT诊断及其临床意义

目的探讨心肌桥-壁冠状动脉(MB-MCA)的多层螺旋CT(MSCT)诊断和与冠脉硬化的关系。方法应用64层螺旋CT对可疑冠心病(CHD)者,行冠状动脉血管成像(CTA),3名CT诊断医师独立判断MB-MCA的存在,结果一致时确定为MB-MCA。测量壁冠状动脉(MCA)长度、肌桥(MB)厚度,结果用平均数±标准差表示,记录MB-MCA近、远段血管形态变化。根据这三项指标,提出载MB-MCA冠脉积分计算方法。确定载MB-MCA冠脉硬化情况,应用秩和统计分析,判断血管硬化与MB-MCA的关系。结果900例可疑CHD者,冠脉CTA发现MB-MCA167例(18.56%,167/900),180处。MB-MCA位于左前降支者占92.78%(167/180)。MSCT显示MCA可被心肌完全包绕(36.11%,65/180)或不完全包绕(63.89%,115/180)。MCA长度为18.7mm±10.2mm。MB厚度为1.7mm±1.2mm。70%的MCA前段和/或远段邻近血管走行迂曲成角。载MB-MCA冠脉积分评分方法MCA长度<10mm、MB不全包绕血管、邻近血管平滑,每项1分;MCA长度10~20mm、MB<1mm、邻近血管一侧成角,每项2分;MCA程度>20mm、MB>1mm、邻近血管近、远段两侧成角,每项3分。167例中,88例可见冠状动脉硬化征象(52.69%),统计学结果提示载MB-MCA冠脉硬化与MB-MCA形态积分无明显相关(u=1.234,P>0.05)。结论64层螺旋CT可用于判断MB-MCA和载MB-MCA冠脉的结构特征;临床怀疑CHD者MB-MCA检出率为18.56%;载MB-MCA冠脉硬化与MB-MCA形态积分无明显相关。

Multi-slice computed tomography of myocardial bridge and mural coronary artery and clinical significance thereof

OBJECTIVE: To investigate the diagnosis of myocardial bridge and mural coronary artery (MB-MCA) with multi-slice computed tomography (MSCT) and clinical significance thereof. METHODS: 900 patients suspected as with coronary artery disease (CHD) underwent 64-slice computed tomography performed by 3 radiologists independently. When consistency was obtained among the independent interpretations of the tomogram among them the diagnosis of MB-MCA could be confirmed. The length of MCA and thickness of MB were measured, and the situation of the nearby arteries were observed and recorded. Based on the above mentioned 3 items the reference scoring criteria were established. RESULTS: 180 sites of MB-NCA were found in 167 (18.56%) of the 900 patients, 112 males and 55 females, aged 54.46 (33 - 84). 167 of the 180 sites of MB-MCA were located on the LAD (92.7%). MCA could be covered by MB in a form of semi-circularity (63.89%, 115/180) or circularity (36.11%, 65/180) The length of MCA was 18.7 mm +/- 10.2 mm, and the thickness of MB was 1.7 mm +/- 1.2 mm. 70% of the arteries proximal and/or distal to the MB-MCA were tortuous. Length of MCA < 10 mm, half-surrounding of MB, and smoothness of the proximal and distant vessels were scored as 1; length of MCA of 10 approximately 20 mm, thickness of MB < 1 mm, and tortuousness of the unilateral proximal or distant vessel were scored as 2; and length of MCA > 20 mm, thickness of MB > 1 mm, and tortuousness of the bilateral proximal and distant vessels were scored as 3. Coronary atherosclerosis was found in 88 of the 167 patients (52.69%). No significant correlation was found between coronary atherosclerosis and MB-MCA grade (u = 1.234, P > 0.05). CONCLUSION: Sixty-four-slice CT can be used to confirm the presence of MB = MCA and the morphology of coronary artery with MB-MCA. Coronary atherosclerosis is not significantly correlated with MB-MCA grade.