新型心肌超声造影软件定量评价心肌梗死治疗前后微循环灌注

摘要

目的 探讨自制新型心肌超声造影软件在定量评价心肌梗死模型治疗前后左室心肌微循环灌注方面的应用价值.方法 将34只SD大鼠分为心肌梗死组(MI组)和促红细胞生成素治疗组(EPO组),分别于术前、术后1周及3周行心肌超声造影检查;应用计算机软件对心肌造影图像进行分割、分区灌注强度标注及彩色编码等自动处理,并获得心肌灌注强度指标—造影剂密度值(CI).CI值与免疫组化微血管密度行相关分析.结果 ①术后1周和3周,与EPO组比较,MI组梗死节段心肌的CI值较低,差异有统计学意义(P＜0.001).EPO组危险节段的CI值在术后1周和3周呈上升趋势,且差异有统计学意义(P＜0.01).②术后3周时,前壁危险节段CI值与免疫组化微血管密度呈正相关(r=0.852,P＜0.01).③彩色编码:术后3周MI组梗死节段心肌明显变薄,呈大片红色渲染,EPO组于前壁、侧壁有小片状红色区域,其他节段显示为绿色和蓝色混杂,与微球染色及TTC染色明显相似.结论 计算机辅助心肌超声造影可以实现对左室心肌微循环灌注的定量评估,在评价梗死心肌治疗效果方面具有较好的应用前景.%Objective To evaluate the feasibility and value of quantitatively assessing left ventricular myocardial perfusion by myocardial contrast echocardiography (MCE) with computer-aided technique in myocardial infarction model.Methods 34 rats were randomly divided into myocardial infarction (MI) group and erythropoietin (EPO) treatment group.Echocardiography and MCE were performed before MI and at 1,3 weeks after MI.Automatic segmentation of the myocardium,a reasonable partition of myocardium,quantitative calculation of myocardial perfusion intensity and color-coded map of the myocardial perfusion were accomplished by computer software.Contrast intensity (CI),a parameter of myocardial perfusion,was acquired.The correlation between CI and immunohistochemical microvascular density was analyzed.Colorcoded map and fluorescent microspheres or triphenyl-tetrazolium chloride (TTC) staining were compared.Results The CI value of infarcted section in MI group at 1 and 3 weeks after MI remained depressed,while the CI value of risk section in EPO group showed an upward trend (P ＜0.001).At 3 weeks after MI,the CI value of anterior wall risk section had a positive correlation with immunohistochemical microvascular density(r =0.852,P ＜0.01).The infarcted segments in MI group were obvious thin at 3 weeks after MI,and showed a large red-coded.The anterior and lateral walls in EPO group showed a small red-coded,while other sections showed green and blue coded map,which were similar to fluorescent microspheres dyed and TTC staining.Conclusions MCE with computer aided software can assess quantitatively left ventricular myocardial microcirculation perfusion,and has good application prospects in the evaluation of treatment effect of animal MI model.