中文摘要：

目的探讨二维斑点追踪技术评价正常犬左室短轴应变的可行性及短轴应变参数与左室收缩功能的关系。方法正常成年犬27只,二维斑点追踪显像技术测量左心室径向应变（radial strain,RS）、圆周应变（circumferential strain,CS）和旋转（rotation,Rot）角度等参数,Simpson法测量左心室射血分数（left ventricular ejection fraction,LVEF）,并分析以上应变参数与Simpson法所测LVEF的相关性。结果左室收缩期RS峰值为正值,中间段最大,心尖段最小,基底段居中;CS峰值为负值,从基底段至心尖段绝对值逐渐增大;Rot绝对值心尖段最大,基底段次之,中间段最小（P〈0.05）;收缩期内膜下心肌RS、CS、Rot均显著高于外膜下心肌（P〈0.05）。左室短轴径向、圆周整体应变及旋转参数与Simpson法所测LVEF相关（r值分别为0.72、0.87、0.80,P〈0.05）。结论二维斑点追踪技术可准确测量正常犬左室短轴应变,左室短轴径向、圆周整体应变和旋转参数是反映左室整体收缩功能的有效指标。

英文摘要：

Objective To explore the feasibility of two-dimensional speckle tracking imaging evaluating healthy adult canines ＇ left ventricular fractional strain and rotation,and the relationship between strain parameters and left ventricular systolic function. Methods We analyzed the fractional strain and rotation（ RS,CS,Rot） of 27 healthy adult canines by using 2DT online analysis software,and evaluated the correlation of these parameters and left ventricular systolic function with Simpson method. Results Left ventricular systolic RS was positive,and RS of papillary muscle level were significantly increased compared with basal and apical level. CS was negative,and the absolute value of the basal segment to apical segment gradually increased. The maximum Rot level was apical level,while the minimum level was papillary muscle level（ P 0. 05）. RS,CS and Rot of different segments of inner layers showed higher than those of the outer layers（ all P0. 05）. GRS,GCS and Rot correlated well with left ventricular systolic function by Simpson method（ r values were 0. 72,0. 87,0. 80 respectively,all P 0. 05）. Conclusions Two-dimensional speckle tracking imaging can evaluate healthy adult canine ＇s left ventricular fractional strain and rotation accurately. Fractional global strain and rotation reflect left ventricular systolic function well.