应用血流向量图比较正常人与心力衰竭患者左心室等容收缩期涡流

目的应用血流向量图(vector flow mapping,VFM)比较心力衰竭(心衰)患者与正常人左室等容收缩期血流动力学特点。方法对照组包括健康志愿者51例,心衰组包括左室射血分数45%的扩张性心肌病患者57例。心尖左室长轴观记录左室彩色多普勒血流信号,应用VFM测量并比较等容收缩期初始帧和终末帧左室腔内涡流流率与面积。结果对照组舒张末期左室涡流经过等容收缩期后面积无显著性变化,但流率显著降低(P0.01);所有涡流范围均达到左室基底部。而心衰组经过等容收缩期后,涡流面积、流率均显著降低(均P0.05);仅有25例(44%)患者涡流范围可达到左室基底部。校正心腔大小的影响后,等容收缩期末左室涡流的面积和流率心衰组均小于对照组(均P0.01)。结论经过等容收缩期后,心衰患者左室涡流的大小与流率均显著降低,且低于正常心脏。

Comparison of the left ventricular intracavitary vortex during the isovolumic contraction period between normal and systolic dysfunction by using vector flow mapping

AIM To compare the left ventricular (LV) intracavitary vortex during the isovolumic contraction (IVC) period between normals and patients with heart failure by using vector flow mapping (VFM). METHODS Color Doppler flow images were recorded from LV apical long-axis view in 51 healthy volunteers and 57 patients with dilated cardiomyopathy and LV ejection fraction ≤45%. RESULTS In normal subjects, the area of the LV intracavitary vortex formed at the end of diastole was sustained and the flow volume significantly decreased during the IVC period (P<0.01). The vortex reached the basal region of LV chamber in all normal subjects. However, both the area and flow volume of the vortex decreased significantly during the IVC period in the patients (both P<0.05). The vortex reached the basal region of LV chamber only in 25(44%) patients. When corrected for the influence of LV size, both the area and the flow volume of the vortex were significantly smaller in the patients than those in the normal subjects at the end of the IVC period (both P<0.01). CONCLUSION Both the area and flow volume of intracavitary vortex significantly decrease during the IVC period in patients with heart failure and are smaller than those in normals.