VFM技术在评估扩张性心肌病患者左室腔内血流能量损耗中的应用

摘要

Objective To study the characteristics of blood flow in isovolumic systole(IVC)of left ventric-ular(LV)in patients with dilated cardiomyopathy by flow-vector imaging(VFM). Methods Color flow Doppler imaging was performed from the apical long-axis view in 58 patients with dilated cardiomyopathy who was admitted in our hospital from October 2015 to November 2016 and 56 healthy volunteers as control. Doppler flow data ob-tained during IVC were analyzed offline with vector flow mapping.Results At the beginning of IVC,the swirl area (15 ± 3)cm2and flow(36 ± 8)cm2/s in the control group were significantly less than those in the observation group (27 ± 8)cm2,(45 ± 12)cm2/s,all P=0.000.At the end of IVC,the vortex flow was similar in both groups[(28 ± 4)cm2/s vs.(29 ± 11)cm2/s,P=0.617)],and the vortex area in the control group was significantly smaller than that in the observation group[(16 ± 3)cm2vs.(24 ± 9)cm2,P=0.000)].During the IVC,the area of the vortex in the control group increased slightly but not significantly(P = 0.073),but the flow rate decreased significantly (10 ± 27%). The area and volume of the vortex in the observation group decreased significantly with the flow de-creased by 29 ± 54%(P=0.000 vs.the control group).When the aortic valve was open,the average blood flow veloc-ity in the middle and basal parts of the LV compartment in the observation group was significantly lower than that in the control group(P<0.05).In multivariate models,a decreased LV ejection fraction was the only independent pre-dictor of the percentage decrease in area of the vortex during the IVC(P < 0.001),and a larger QRS width(P =0.026)and LV end-systolic long diameter(P = 0.004)were independent predictors of the percentage decrease in flow volume of the vortex. Conclusion The VFM technique enables a better assessment of the pathophysiological state of LV lumen energy loss during IVC in patients with dilated cardiomyopathy by vortex imaging.%目的 通过血流向量成像(VFM)来研究扩张性心肌病患者左心室(LV)腔内在等容收缩期(IVC)的血流特征.方法 对2015年10月至2016年11月本院收治的58例扩张性心肌病患者(观察组)和56例健康志愿者(对照组)的心尖长轴切面进行彩色多普旋涡勒血流显像.在离线VFM工作站上分析IVC期间的血流信号.结果 在IVC开始时,对照组漩涡的面积(15 ± 3)cm2和流量(36 ± 8)cm2/s均显著小于观察组[(27 ± 8)cm2,(45 ± 12)cm2/s,均P=0.000].在IVC结束时,两组涡旋流量相似[(28 ± 4)cm2/s vs.(29 ± 11) cm2/s,P=0.617],对照组旋涡的面积显著小于观察组[(16 ± 3)cm2vs.(24 ± 9)cm2,P=0.000].在IVC期间,对照组旋涡的面积轻微增加并不显著(P=0.073),但流量明显减少[(10 ± 27)%];观察组旋涡的面积和流量均显著下降,其中流量减少了(29 ± 54)%,与对照组相比,差异有统计学意义(P=0.000).当主动脉瓣开口时,观察组在LV室的中部和基底部的平均血流速度均显著低于对照组(P<0.05).在多变量模型中,左心室射血分数减少是IVC期间旋涡面积百分比下降的唯一独立预测因子(P=0.000),QRS宽度(P=0.026)和左心室收缩末期长径(P=0.004)是旋涡流量百分比减少的独立预测因子.结论 VFM技术能够通过旋涡显像更好地评估扩张性心肌病患者的IVC期间LV腔内血流能量损耗的病理生理状态.