超声二维斑点追踪技术对单纯冠状动脉左前降支狭窄患者左心室收缩功能的评价

目的探讨二维纵向应变(LS)、左心室壁整体扭转角度(LV-tor)在二维超声未探及左心室壁运动异常,而冠状动脉存在单纯左前降支(LAD)不同程度狭窄时,对左心室壁节段及整体收缩功能改变的评价价值。方法入选行冠状动脉造影的患者75例,取造影正常者27例为对照组,而单纯LAD狭窄50%～75%的患者25例(A组)、单纯LAD狭窄≥75%的患者23例(B组),分别采集常规超声心动图的心尖两腔、心尖左心室长轴切面及左心室短轴基底水平、心尖水平切面的16个室壁阶段二维灰阶图像。应用GE Echo PAC软件测量仅由LAD供血的相应左心室壁节段收缩期峰值的LS,以及左心室基底段总扭转角度(Rot-base)、心尖段总扭转角度(Rot-apex)并计算出LV-tor,静息状态下应用M型超声测定左心室壁运动幅度、左心室射血分数(LVEF)、短轴缩短率(FS)等常规参数。结果 A组与对照组比较,LS值和LV-tor的差异均无统计学意义(均为P>0.05)。B组与对照组、A组比较,LAD供应左心室壁相应节段的LS值(-24.2±1.8比-25.2±1.8和-25.1±1.4,P=0.037)和LV-tor(16.4±1.2比17.2±1.1和16.7±1.1,P=0.041)差异均有统计学意义;而3组间比较,LVEF和FS等差异均无统计学意义(均为P>0.05)。结论当单纯LAD狭窄率≥75%时,LS值可敏感地反映出左心室壁节段收缩功能改变,而LV-tor可敏感地反映出左心室壁整体收缩功能的改变;左心室壁除相应节段出现收缩功能减低外,整体收缩功能也受到影响。

Assessment of left ventricular systolic function in patients with left anterior descending artery single vessel disease by two-dimensional speckle tracking imaging

Objective To evaluate left ventricular global and regional systolic function by two-dimensional speckle tracking imaging in patients with left anterior descending artery(LAD) single vessel disease. Methods A total of 75 patients underwent coronary angiography were enrolled.Of those 27 with normal coronary angiogram as control group,25 patients with LAD single vessel lesion between 50% and 75% stenosis as group A,and 23 with LAD single vessel lesion more than 75% stenosis as group B.High frame rate two-dimensional images were recorded from the apical two-chamber view,long-axis view of the left ventricle and the left ventricular short-axis views at the levels of mitral va1ve and apex by Echocardiography.longitudinal Strain(LS) of the segments supplied by LAD,the peak basal and apical rotation(Rot-base,Rot-apex) in basal and apical plane and peak LV-tor were calculated using Echo PAC software.Left ventricular wall motion amplitude,left ventricular ejection fraction(LVEF) and fractional shortening(FS) were measured by M-mode ultrasound under resting state. Results No significant difference was found for LS and LV-tor between group A and control group(P>0.05).Compared to control group and group A,LS of the segments supplied by LAD(-24.2±1.8 vs.25.2±1.8 and 25.1±1.4,both P=0.037) and LV-tor(16.4±1.2 vs.17.2±1.1 and 16.7±1.1,both P=0.041) was significantly decreased in group B.LVEF and FS were similar among three groups(P>0.05). Conclusions LS and LV-tor decreased suggests left ventricular regional and global systolic function are affected in patients with LAD single vessel disease with ≥75% stenosis.