高频超声心动图评价心梗小鼠左室整体功能和节段性室壁运动异常

目的 通过建立小鼠心梗模型,探讨应用超高分辨率超声系统评价心梗小鼠心脏结构及心功能方面的应用价值.方法 25只雄性C57BL/6小鼠随机分为2组,即开胸结扎左冠状动脉前降支建立心梗模型组(n=15)和仅在相同结扎位置穿针,不结扎的方法建立假手术组(n=10).术前3 d和术后1周采用二维、M型、脉冲多普勒(PWD)、组织多普勒(TDI)和EKVTM超声技术对心梗小鼠心脏形态结构、室壁运动以及心功能进行评价.术后1周,取小鼠心脏进行HE染色并观察心肌组织结构.结果 二维超声与HE色染均显示,心梗模型组心肌有明显的梗死区;心梗模型组与假手术组比较,心室明显扩大,室壁明显变薄,心室收缩功能与舒张功能均显著下降(P<0.05);局部室壁运动受阻严重,心室发生重构.结论 采用2D超声心动图联合M型、PWD、TDI以及EKVTM超声心动图观察小鼠心梗模型能够更精准敏感地判断心肌梗死位置和梗死程度,为临床心肌梗死诊断、治疗和预后评估提供了参考价值.

High-frequency echocardiography for assessment of regional wall motion abnormality and cardiac function in mice with myocardial infarction

Objective To evaluate the value of high-frequency echocardiography in assessing cardiac structure and function in a mouse model of myocardial infarction. Methods Twenty-five C57BL/6 mice were randomly divided into sham-operated group (n=10) and myocardial infarction model group (n=15) established by ligation of the left anterior descending artery. The cardiac structure, regional wall motion and cardiac function of mice were examined with pulsed wave Doppler (PWD), tissue Doppler imaging (TDI), EKV and M-mode echocardiography 3 days before and at 1 week after the operation. The histological changes and myocardial structure of the heart were observed at 1 week after the operation. Results High-frequency echocardiography and HE staining detected obvious myocardial infarction in the mice in the model group. Compared with the sham-operated mice, the mice with myocardial infarction showed significant left ventricular expansion, obvious thinning of the ventricular wall, and significantly decreased ventricular systolic function and diastolic function with regional wall motion abnormality and ventricular remodeling. Conclusions 2D-type echocardiography combined with M-mode, PWD, TDI and EKVTM for allows accurate and sensitive detection of the loci and severity of myocardial infarction to provide important evidence for clinical diagnosis and treatment of myocardial infarction.