通过二维应变及应变率评价心肌梗死小鼠心脏纤维化及远期死亡率  

Assessment of Cardiac Fibrosis and Long-term Mortality After Myocardial Infarction Using Two-dimensional Speckle Tracking Imaging in Mice

作　　者：陶瑾 李昊 徐昊辰 王浩[1] TAO Jin;LI Hao;XU Hao-chen;WANG Hao(Department of Ultrasound,Fuwai Hospital,National Center for Cardiovascular Diseases,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100037,China;State Key Laboratory of Cardiovascular Disease,Fuwai Hospital,National Center for Cardiovascular Diseases,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100037,China)

机构地区：[1]北京协和医学院中国医学科学院国家心血管病中心阜外医院超声影像中心,北京市100037 [2]北京协和医学院中国医学科学院国家心血管病中心阜外医院心血管疾病国家重点实验室,北京市100037

出　　处：《中国分子心脏病学杂志》2019年第1期2721-2724,共4页Molecular Cardiology of China

基　　金：国家自然科学基金(81800263);中央高校基本科研业务费专项资金(3332018050)

摘　　要：目的探讨超声二维斑点追踪成像(speckle tracking imaging,STI)技术在评价小鼠心肌梗死(myocardial infarction, MI)后心脏纤维化及远期死亡率中的应用。方法12周龄C57BL/6雄性小鼠行左冠状动脉前降支结扎造成心肌梗死,在梗死后第3天行常规超声心动图检测,采集胸骨旁长轴左心室二维图像,测量并计算左室前壁厚度(LVAWd)、左室射血分数(EF%)等参数。进而采用STI模块,测量长轴径向二维应变(radialstrain,RS)和应变率(radialstrain rate,RSR)等参数。心脏取材后置于4%多聚甲醛中固定,石蜡包埋,行HE染色和天狼猩红染色。结果心肌梗死后3天,MI组小鼠LVAWd与Sham组相比显著减小(0.66±0.03) mm vs (0.56±0.24) mm,P<0.01),EF(%)下降(69.1%±2.90%vs44.7%±3.87%,P<0.001)。此外,MI组小鼠左室RS及RSR与Sham组相比均显著降低。依据心肌梗死后小鼠RS值进行分组,通过连续随访发现RS<11%组小鼠与RS>11%组小鼠相比,心肌梗死后死亡率及心脏胶原沉积程度均显著增加。结论RS具有准确的早期预测小鼠心肌梗死后左心室胶原沉积程度及远期死亡率的价值。Objective To eexplore the application of speckle tracking imaging (STI) in evaluatingcardiac fibrosis and long term mortality after myocardial infarction (MI) in mice. Methods LAD ligation or sham operation were randomly performedin male C57BL/6 mice. Echocardiography was performed on day 3 of surgery. B-mode and M-mode images from the parasternallong axis view of the leftventricle were obtained, LV anterior wall thicknessat diastole (LVAWd) and ejection fraction(EF%) were measured and calculated. The variables of radial strain (RS) and radial strain rate(RSR) were derived by STI. Hearts were fixed with 4% paraformaldehyde andembedded in paraffin, sections were stained withhaematoxylin and eosin and Picrosirius red. Results LVAWd and EF (%) were significantly decreased in MI group compared with Sham group 3 days after ligation. Furthermore, RS and RSR were also significantly decreased. Then, mice were separated in two groups according to RS value after myocardial infarction. Notably, it was found that the mortality and cardiac collagen deposition in RS<11% group were significantly higher than those in RS>11% group. Conclusion STI provides a new and precise method for evaluation of left ventricular collagen deposition and long-term mortality after MI in mice.

关 键 词：心脏纤维化 心肌梗死 小鼠 应变 

分 类 号：R542.22[医药卫生—心血管疾病]