【摘要】 目的探讨应用不同参数的速度向量成像技术(VVI)评价犬左心室舒缩功能的价值。方法健康杂种犬6只,开胸后制备不同程度冠状动脉狭窄。分别以左心室舒张末压(LVEDP)、左心室压力最大上升速率(+dp/dtmax)为标准,评价应用VVI不同参数包括二尖瓣环长轴上的平均峰值舒张和收缩速度(Em和Sm)、舒张期和收缩期峰值应变率(Esr和Ssr)以及常规超声左心室射血分数(EF)等评估左心室舒缩功能的价值。结果Em和Esr均与LVEDP呈负线性相关(r=-0.834,P<0.001;r=-0.703,P<0.001,两相关系数间比较P=0.032)。Sm、Ssr和EF均与+dp/dtmax呈正相关(r分别为0.883、0.772、0.647;P<0.001);其中Sm与+dp/dtmax相关性最高(P<0.05)。结论VVI测量Em和Sm能准确评价左心室舒张及收缩功能,VVI通过测量Em评价左心室舒张功能优于Esr,应用Sm评价左心室收缩功能优于EF和Ssr。更多还原

【Abstract】 Objective To evaluate left ventricular diastolic and systolic function of the dogs during different status of acute myocardial ischemia with velocity vector imaging(VVI).Methods Six healthy mongrel dogs were enrolled.Home-made artery constrictor was placed in the proximal coronary artery after opening the chest of dogs to produced different grades of coronary artery stenosis.Mean of peak diastolic velocity(Em),peak strain rate of diastole(Esr),mean of peak systolic velocity(Sm),peak strain rate of systole(Ssr),ejection fraction(EF) and left ventricular pressure were measured.Results There was good linear correlation between Em and Esr by VVI and left ventricular end diastolic pressure(LVEDP)(r=-0.834,P<0.001 and r=-0.703,P<0.001,respectively).Em and LVEDP had better correlation than that between Esr and LVEDP(P=0.032).Sm,Ssr or EF had significant correlation with +dp/dtmax(r=0.883,P<0.001,r=0.772,P<0.001 and r=0.647,P<0.001,respectively).Significant difference was observed for correlation coefficient between Em and Esr and EF(P<0.001).Conclusion Em and Sm are sensitive echocardiography indexes to evaluate left ventricular diastolic and systolic function,and are better than EF,Esr and Ssr.更多还原