血流向量成像定量评价正常成人左心室涡流特征  

Quantitive Evaluation on Left Ventricular Vortex Characteristic in Normal Adults

作　　者：张瑜[1] 丁云川[1] 王庆慧[1] 陈剑[1] 尹帆[1] 苏璇[1] 罗庆祎[1] 李建华[1] 现丽妮[1] 

机构地区：[1]昆明医科大学附属延安医院医学影像科昆明市医学超声诊断中心,云南昆明650051

出　　处：《昆明医科大学学报》2015年第10期36-40,共5页Journal of Kunming Medical University

基　　金：云南省科技厅-昆明医科大学应用基础研究联合专项基金资助项目(2012FB100)

摘　　要：目的应用血流向量成像(vector flowmapping,VFM)技术定量评价正常成年人不同心动周期左心室涡流的变化特征.方法在VFM模式下采集50例健康成人心尖三腔与四腔切面彩色多普勒动态图像,应用配备VFM5.0版本分析软件的DAS-RSI工作站脱机分析,观察心动周期不同时相左室腔内涡流的2D速度分布、流线、涡量线、涡量、循环、能量损耗、室壁切应力等参数,分析涡流的变化特征.结果左室腔内涡流在不同心动周期呈规律变化,且涡流多持续在等容收缩期,左心室内部分有涡流的时相中,涡流横径(Dx)、纵径(Dy)及边缘最大速度(Vmax)差异有统计学意义(P<0.05);循环反应了局部涡流旋转的方向和强度的总和,即总涡量,当流速增大时,循环增大,循环值的大小取决于指定的闭合曲线的大小;在涡量变化大的位点能量损耗就大,在层流的位点能量损耗就小;室壁切应力与正交方向的速度梯度成正比,红色节段室壁切应力较蓝色节段大.结论 VFM技术可以反映正常人左室腔内涡流变化规律,为定量评估左室内血流状态提供了一种新的方法.Objective To evaluate quantitatively the left ventricular vortex changes characteristic in normal adults using vector flow mapping（VFM）.Methods Fifty normal adults were examined by ALOKA a- l0 ultrasonic diagnostic system.The color Doppler loops in apical three- and four- chamber view were Recorded and then analyzed off- line by VFM software version 5.0 in DAS- RSI system.The evolutions of left ventricular vortex within each phase of the cardiac cycle, and 2D velocity distribution, stream line, vorticity line, vorticity,circulation, energy loss and wall shear stress were observed.Results Left ventricular vortex showed regular changes within the cardiac cycle.The vortex mostly lasted during the isovolumic contraction interval.The transverse diameter（Dx）, longitudinal diameter（Dy） and the maximum speed（Vmax） of the edge were significantly different in some cardiac cycles（P〈0.05）.Circulation reflect the direction and the intensity of rotation of the local vortex,namely the total vorticity,circulation increase when the flow rate increases,circulation value also depends on the size of the specified closed- curve.At the site of large changes in vorticity is accompanied by greater energy loss,and the energy loss of laminar flow is smaller.Wall shear stress is directly proportional to the velocity gradient on the orthogonal direction,and the wall shear stress of red- color ventricular segment is higher than that of the blue- color segment.Conclusion The VFM technology can be used to observe the change rules of left ventricular vortex,and may serve as a novel approach to quantitatively evaluate the flow state.

关 键 词：血流向量成像 涡流 左心室 

分 类 号：R445.1[医药卫生—影像医学与核医学]