PC-MRA对Stanford B型主动脉夹层血流动力学与顺应性的研究  

Hemodynamics and compliance of Stanford type B aortic dissection:a phase-contrast MR angiography study

作　　者：耿冀[1] 范占明[2] 李宇[2] 辛海燕[2] 张楠[2] 

机构地区：[1]北京大学首钢医院医学影像中心,北京100144 [2]首都医科大学附属北京安贞医院放射科,北京100029

出　　处：《首都医科大学学报》2013年第3期333-338,共6页Journal of Capital Medical University

基　　金：国家自然科学基金面上项目(30970822)~~

摘　　要：目的利用相位对比磁共振血管成像对主动脉夹层(Stanford B型)的血流动力学和顺应性进行研究。方法 25例诊断Stanford B型主动脉夹层患者,覆膜支架腔内隔绝术前行相位对比磁共振血管成像。分别采集6个主动脉层面:①升主动脉瓣上肺动脉分叉水平;②主动脉弓水平;③降主动脉破口以远2 cm水平;④膈水平;⑤平较低支肾动脉下1 cm水平;⑥腹主动脉近髂分叉水平。对图像数据进行定量分析,测量各层面1个心动周期内真腔与假腔的平均横断面积、血流指标(平均血流速度、平均血流量和净流量),并计算真腔与假腔的顺应性。比较真、假腔平均横断面积、血流指标、顺应性的差异及真、假腔顺应性的相关性。相关性应用Pearson相关分析,差异比较应用Paired t-test统计学方法。结果在③～⑥层面水平,所有患者的真腔平均横断面积均小于假腔平均横断面积(P<0.05);真腔内平均血流速度均高于假腔内平均血流速度(P=0.000)。在⑤、⑥层面水平,真腔内平均血流量、净流量均高于假腔内平均血流量、净流量(P<0.05)。在③、⑥层面水平,真腔的顺应性高于假腔的顺应性(P<0.05),并且二者呈明显正相关(r=0.667,P=0.001;r=0.545,P=0.019)。结论相位对比磁共振血管成像能够定量测定主动脉夹层真腔和假腔的血流动力学指标与真假腔顺应性,为临床Stanford B型主动脉夹层患者提供了一种无创的血流动力学监测手段。Objective To evaluate the characteristics of hemodynamics and compliance using phase-contrast magnetic resonance angiography （ PC - MRA） in Stanford type B aortic dissection patients. Methods A total of 25 consecutive patients with Stanford type B aortic dissection identified by computed tomography angiography were recruited in this study. All patients underwent PC - MRA before operation. The cross-sectional images of aorta for PC - MRA were acquired at the following 6 locations： ①pulmonary bifurcation;②aortic arch; ③2 cm distal to the entry; ④diaphragm; ⑤1 cm distal to the lower renal artery; ⑥aorta-iliac bifurcation. Mean area, flow characteristics （including mean velocity, mean flow volume, net volume） of true and false lumens within one cardiac cycle were measured by using PC - MRA. The compliances of true and false lumens were also calculated. Paired t-test and Pearson correlation analysis were involved in statistical analysisResults The mean area of true lumen was significantly smaller than that of false lumen at location ③ -⑥ （ P 〈 0. 05 ） ; the mean velocity in true lumen was significantly higher than that in false lumen at ③ -⑥ levels （ P = 0. 000）. At location ⑤,⑥, the mean flow volume and net volume in true lumen were significantly higher than that in false lumen （P 〈 0. 05 ）. At location ③ 、⑥, the compliance of true lumen was significantly higher than that of false lumen （ P 〈 0. 05 ）, and positive correlation were found between them （ r = 0. 667, P = 0. 001 ; r = 0. 545, P = 0. 019）. Conclusion PC - MRA can quantitatively measure flow characteristics and compliance of true and false lumen in Stanford type B aortic dissection. It is important to provide a noninvasive hemodynamic monitoring tool for Stanford type B aortic dissection.

关 键 词：主动脉夹层 磁共振血管成像 相位对比 血流动力学 顺应性 

分 类 号：R554.1[医药卫生—血液循环系统疾病]