Evaluation of protect effects of ischemia postconditioning on myocardial reperfusion injury using ultrasound speckle tracking imaging / 中华超声影像学杂志

ABSTRACT

Objective To evaluate left ventricular myocardial function of rabbit after ischemiareperfusion using speckle tracking imaging (STI),and to explore the myocardial protect effects of ischemia postconditioning (I-PostC) on reperfusion injury.Methods 24 Japanese rabbits were divided into ischemiareperfusion group (group Ⅰ) and I-PostC group (group Ⅱ) randomly.The characteristic changes of left ventricular global and regional myocardial strain and twist function of two groups were evaluated quantitatively by STI and compared with pathological results.Results ① Global longitudinal systolic strain rate(GLSrsys),global longitudinal systolic strain (GLSsys) and global longitudinal peak strain(GLSp) decreased in both groups,longitudinal systolic strain rate(SrLsys),longitudinal systolic strain(SLsys) and longitudinal peak strain(SLp) in the lateral wall of left ventricle decreased significantly and negative peak of SrLivr and PSI increased after the left ventricular branch of coronary artery was occluded;The values of Ptw and untwR of left ventricle were smaller.② After the artery was released,GLSp recovered in group Ⅱ,which was not seen in group Ⅰ.The values of SrLsys,SLsys and SLp increased significantly and negative peak of SrLivr and PSI decreased in group Ⅱ.However,only Slsys and SLp rebounded in group Ⅰ.Between the 2 groups,SrLsys andSLp in group Ⅱ were higher than that of group Ⅰ (P＜0.05 or 0.01),and SrLivr was lower compared with group Ⅰ (P ＜0.05).In group Ⅱ,Ptw and untwR changed back to a normal range (P ＜0.05 or 0.01),and no index has changed in group Ⅰ ;Between the 2 groups,Ptw and untwR in group Ⅱ were higher than that of group Ⅰ (P ＜0.05).③ The sensitivity and specificity of GLSrsys,GLSsys,SrLsys,SLsys and Ptw to detect rabbit myocardial infarction were 81.3 ％ and 75.0 ％,62.5 ％ and 81.2％,87.5％ and 87.5％,93.8％ and 75.0％,81.3％ and 68.7％ respectively.Conclusions STI may provide a promising approach to evaluate the global and regional myocardial function.It also can observe the protect effects of I-PostC on myocardial reperfusion injury accurately.