超声血流向量成像评价心肌梗死患者左心室节段性血流结构变化

Vector flow mapping evaluation of regional left ventricular flow structure in patients with myocardial infarction

目的应用血流向量成像（VFM）显示左室内血流变化情况，观察血流在心肌梗死节段运动状态并量化分析其改变，评价心肌梗死状态对心腔内血流的影响。方法选取陈旧性心肌梗死患者28例，正常对照30例为观察对象，利用VFM技术采集左心室内血流向量图像，应用VFM分析软件DSA-RSl测量心尖左室长轴观及心尖四腔观不同节段时间一流量（T—F）的变化及在收缩与舒张期峰值处相应的血流参数：垂直于取样线方向的向量速度测值（NVP），平行于取样线方向的向量速度测值（PVP），取样线上综合向量测值（VP），取样线所通过的流量测值（FP）变化情况。结果T—F曲线显示心肌梗死节段收缩期峰值s、舒张期峰值E、心房收缩期峰值A较正常对照组均明显减低，时间延迟（P〈0．05）。心肌梗死节段收缩期峰值s及舒张期峰值E处相应的血流参数PVP及FP均有所减低（P〈O．05）。结论心肌梗死患者心肌梗死节段血流速度较正常节段明显减低，达峰时间延长，VFM是一种有效的评价心肌梗死患者梗死节段室壁运动异常所引起的血流动力学变化的新方法。

Objective To evaluate blood flow structure within left ventricle,quantify the variation of the flow at infarct segments, and assess the impact of myocardial infarction. Methods Twenty-eight patients with chronic myocardial infarction （CMI） and 30 healthy controls were involved. The flow vector images on the section plane of the flow within the left ventricle were acquired by vector flow mapping （VFM）. Time- flow（T-F） curve and all other peak systolic and diastolic flow curve include normal velocity profile, parallel velocity profile, vector profile were analyzed by DSA-RS1 program. Results Ventricular ejction peak S, rapid ventricular filling peak E and atrial systole peak A were relatively lower in CMI group at infarct segment than normal control group, the time duration from bottom to peak was relatively longer in CMI group. Normal velocity profile, parallel velocity profile, vector profile, flow profile at peak S and E were lower in CMI group than normal group. Conclusions The velocity of CMI group was lower and the time to peak was longer than that of control group. VFM is a new noninvasive and clinically useful parameter for the evaluation of regional left ventricular segment flow dynamics.