应用血流向量成像观察扩张型心肌病左心室内涡流特征

目的 应用血流向量成像技术观察左室内涡流的形成及演变情况,评价扩张型心肌病(DCM)的左心室功能.方法 选取DCM患者26例、正常对照44例为观察对象,采集左室内血流向量图像,观察心动周期中不同时相涡流的位置、大小、圈数分布及其演变规律.结果 ①正常对照组缓慢射血期和等容舒张期左室内未见涡流形成,舒张期涡流多位于二尖瓣前叶附近,左室中上部1/3,形态多变(变化2～3次);涡流横径、纵径和圈数在心动周期的7个时相之间有差异.②DCM组心动周期7个时相均有涡流出现,舒张期出现涡流更靠近左室中下2/3,向心尖部靠近,相对正常人而言,DCM组在同一时相出现的涡流形态、部位变化更多(4～5次);心动周期的各个时相中DCM组左室内涡流的横径、纵径和圈数均大于正常对照组.DCM组涡流大小和圈数在心动周期的7个时相之间也有差异.结论 血流向量成像技术可以显示在体的左室内涡流变化情况,DCM患者左室内涡流大小及圈数均大于正常人.

Evaluation of vortex within left ventricle in patients with dilated cardiomyopathy by vector flow mapping

Objective To evaluate left ventricular function in the way of intracavitary vortex by vector flow mapping(VFM),and to demonstrate the formation and variation of the vortex. Methods Twenty-six patients with dilated cardiomyopathy(DCM) and 44 healthy controls were involved. The velocity distribution imagings on the section plane of the flow in the left ventricle were obtained by VFM, the location of the vortex and its variation in every phase of cardiac cycle were focused,and series parameters were measured,such as the diameter of the vortex (transverse diameter, vertical diameter), number of the vertex. Results relaxation(e) period. Vortices were observed mostly during diastolic period, nearby the anterior leaflet of mitral valve,middle upper 1/3 of left ventricle,and their shapes changed 2 - 3 times. The diameters of the vortex (transverse diameter,vertical diameter) , number of the vertices in one cardiac cycle during 7 phases mostly nearby the cardiac apex, middle lower 2/3 of left ventricle, and their shapes changed 4 - 5 times.Compared with control group,the diameters of the vortex (transverse diameter, vertical diameter) during 7 phases in DCM group were bigger,and number of the vertices were more ( P ＜0.01 ). The diameters of the vortex (transverse diameter, vertical diameter), number of the vertices within DCM group in one cardiac cycle during 7 phases were significantly different ( P ＜ 0.01 ). Conclusions VFM can demonstrate the variation of intracavitary vortex. Vortex in DCM group were significantly bigger than those of control group.