应用VFM技术评价扩张型心肌病收缩期左心室心腔内血流动力学变化

Evaluation on left ventricular systolic hemodynamics with VFM in patients with dilated cardiomyopathy

目的探讨血流向量成像(VFM)技术在评价扩张型心肌病(DCM)收缩期左心室心腔内血流动力学变化及收缩功能变化中的应用价值。方法病例组:DCM患者30例;对照组:健康志愿者40名。在VFM成像模式下测量并比较两组收缩期峰值流速(Vs)、峰值流量(Fs)和收缩期负向总流量(SQ-);应用Simpson双平面法获取左心室射血分数(LVEF),与三腔心的Vs、Fs、SQ-均值进行相关性分析;同时观察并描述病例组收缩期左心室心腔内涡流的分布特征。结果病例组基底段、中间段及心尖段Vs、Fs、SQ-均值明显低于对照组(P<0.01);两组组内比较各项指标均由基底段至心尖段逐渐递减(P<0.05);LVEF与Vs、Fs、SQ-均值呈明显正相关,相关系数分别为0.727、0.698、0.709(P<0.01);病例组在收缩期3个时相均有涡流出现,直径及圈数较对照组增多。结论 VFM技术可直观、定量评价DCM患者左心室内血流流场变化,进而显示其与左心室收缩功能的关系,有望成为临床检测DCM左心室收缩功能的一种新方法。

Objective To investigate the application value of vector flow mapping（VFM） in evaluation on left ventricular systolic function and changes in the hemodynamics of dilated cardiomyopathy（DCM） patients.Methods Thirty DCM patients were enrolled as patient group,while 40 healthy volunteers were taken as control group.Systolic velocity（Vs）,systolic flow（Fs） and systole Q-（SQ-） of the two groups were measured and compared with VFM.Left ventricular ejection fraction（LVEF） was obtained with biplane Simpson method.Correlation analysis was performed between EF and Vs,Fs and SQ-.Meanwhile,the characteristics of the vortex distribution in left ventricle of DCM patients were observed.Results Value of Vs,Fs,SQ-of basal,middle,apical segments in the patients group were significantly lower than those of the control group（P〈0.01）.Comparison of these indicators of both groups showed a gradually decreasing trend from the basal to apical segments（P〈0.05）.Significant positive correlation（P〈0.01） was found between LVEF and Vs,Fs,SQ-（r=0.727,0.698,0.709,respectively）.Vortexes were observed in all the three systolic phases in DCM patients,and the number and diameter of vortexes were much larger than those of the control group.Conclusion VFM technology could provide more quantitative and intuitive information about changes of blood flow in left ventricular cavity of DCM patients.It is possible to become a useful clinical tool,which is helpful to further understanding of the systolic function of DCM patients.