应变及应变率的速度向量成像定量分析诊断猪心肌挫伤

Diagnosis of Early Myocardial Contusion in Pigs by Velocity Vector Imaging and Quantitative Analysis of Strain and Strain Rate

目的探讨应变(strain,ε)、应变率(strain rate,SR)的速度向量成像(velocity vector imaging,VVI)定量分析对猪心肌挫伤(myocardial contusion,MC)的早期诊断价值。方法建立8只猪MC模型。分别于撞击前及撞击后0.5、2、4、8h,采集左室二尖瓣、乳头肌、心尖水平短轴切面VVI动态图像,利用VVI脱机分析软件获得左室短轴各节段径向峰值ε、SR。结果撞击后MC节段左室径向峰值ε及SR测值低于撞击前(P<0.05),损伤节段的径向峰值ε及SR测值低于非损伤节段(P<0.05)。结论 VVI技术能够定量评价MC后室壁运动异常,为MC早期诊断提供了新方法。

Objective To investigate the diagnostic value of velocity vector imaging （VVI） and quantitative analysis of strain （ε） and strain rate （SR） in the early myocardial contusion （MC） of pigs.Methods MC models were established in eight pigs.Two-dimensional dynamic gray-scale images of three standard left ventricular short-axis views at the levels of mitral annulus,papillary muscle and apex were acquired 0.5,2,4 and 8 hours after MC and transferred to VVI workstation for off-line analysis.Peak systolic ε and SR of all segments of left ventricular at the levels of papillary muscle were measured.Results Compared with the baseline,the peak racial ε and SR levels after MC were significantly decreased （P0.05）,and significantly lower in the injuried site than in the normal site （P0.05）.Conclusion VVI can quantitatively evaluate the motion abnormality in the interventricular wall of MC,and supplies a new method for the early diagnosis of MC.