血流向量成像技术在正常人左心室涡流特征研究中的应用

Application of vector flow mapping in study of left ventricular vortex characteristic in normal adults

目的应用血流向量成像(vector flow mapping,VFM)技术研究正常成年人左心室涡流变化特点。方法在VFM模式下采集30例健康志愿者心尖五腔切面彩色多普勒动态图像,应用配备VFM分析软件的DAS-RSI工作站脱机分析,观察心动周期各个时相左室腔内涡流形态、分布演变规律,通过测量涡流峰值流量、半流量面积、半流量直径及强度等参数,分析涡流变化特点。结果左室腔内涡流在心动周期各个时相呈现规律性变化,等容舒张期左室腔内涡流不明显,舒张期早期在流入道两侧出现局部小涡流,舒张晚期涡流占据大部分左室腔;等容收缩期整体涡流持续存在,强度进一步增加;收缩期整体涡流消失,在主动脉瓣口出现高强度涡流,涡流强度达到最大值。结论血流向量成像技术可以反映正常人左室腔内涡流变化特点。

Objective To study the left ventricular vortex changes characterisitic in normal adults using vector flow map ping （VFM）. Methods Thirty normal adults were examined by ALOKAal0 ultrasonic diagnostic system, and acquired the color Doppler images in apical five-chamber. Recorded loops were analyzed off-line by VFM software in DAS-RSI system. The evolutions of left venticular vortex within each phase of the cardiac cycle, and quantify parameters including maximum flow vol- ume of vortex （Qmax） , half-value area of vortex （S）, halPvolue diameter of vortex （D）, and vortex intensity （VI） were ob- served. Results Left ventricular vortex showed regular changes within the cardiac cycle. In isovolumic relaxation, few vortex appeared in left ventricle. In early diastolic phase, a little vortex appeared in the both sides of the inflow tract. In late diastolic phase, the large whole vortex was filled with left ventricular. In isovolumic contraction phase, the large whole vortex contin- ued, and the intensity o{ vortex increased. However, in contraction phase, the large vortex disappeared, and was followed by a local small high-intensitive vortex around the aortic valve. Conclusion The VFM technology can be used to observe the change rules of left ventricular vortex.