超声二维斑点追踪技术评价小鼠心肌梗死后节段性室壁运动异常  

Assessment of Regional Wall Motion Abnormality after Myocardial Infarction Using Two-dimensional Speckle Tracking Imaging in Mice

作　　者：李昊[1] 张幼怡[2] 沈蔷[2] 陶瑾[3] 崔永春[1] 唐跃[1] 

机构地区：[1]中国医学科学院北京协和医学院国家心血管病中心阜外心血管病医院心血管疾病国家重点实验室实验动物中心,北京市100037 [2]北京大学第三医院心内科血管医学研究所卫生部心血管分子生物学与调节肽重点实室分子心血管教育部重点实验室,北京市100191 [3]中国医学科学院北京协和医学院国家心血管病中心阜外心血管病医院超声科,北京市100037

出　　处：《中国分子心脏病学杂志》2015年第3期1354-1358,共5页Molecular Cardiology of China

基　　金：国家高技术研究发展计划(863计划)(2212AA022403);国家自然科学基金项目(81030001;81200213)

摘　　要：目的探讨超声二维斑点追踪成像(speckle tracking imaging,STI)技术评价小鼠心肌梗死(myocardial infarction,MI)后节段性室壁运动异常的方法。方法 10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7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,测量并计算左室后壁厚度(LVPWd)、左室射血分数(EF%)等参数。进而采用STI模块,测量运动峰值速度(Peak velocity)和加速时间(Time to peak)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7天,小鼠心脏间质出现显著胶原沉积。超声心动图提示MI组LVPWd与Sham组相比显著减小(0.66±0.02 mm vs 0.54±0.03 mm,P<0.01),EF(%)下降(71.6±1.69%vs 32.6±3.00%,P<0.001)。STI技术-向量分析示心肌梗死后室壁运动明显降低,室壁运动速度-时间曲线则进一步明确MI组存在明显心肌反向运动。节段性分析示MI组各节段的室壁峰值速度均小于相应节段的Sham组(均P<0.001),加速时间均长于相应节段的Sham组(均P<0.01)。结论应用STI技术可实现对于小鼠急性心肌梗死后节段性室壁运动变化的定性、定位和定量分析。Object To explore the application of speckle tracking imaging （STI） in evaluating regional wall motion abnormality after myocardial infarction （MI） in mice. Methods LAD ligation or sham operation were randomly performed in male C57BL/6 mice. Echocardiography was performed on day 7 of surgery. B-mode and M-mode images from the parasternal long axis view of the left ventricle were obtained, LV posterior wall thickness at diastole （LVPWd） and ejection fraction （EF%） were measured and calculated. The variables of Peak velocity and Time to peak were derived by STI. Hearts were fixed with 4% paraformaldehyde and embedded in paraffin, sections were stained with haematoxylin and eosin and Picrosirius red. Results Mice of MI group exhibited marked collagen deposition, LVPWd and EF （%） were significantly decreased compared with Sham group. STI-veetor analysis showed the velocity of ventricular wall motion were markedly decline after MI. Moreover, velocity-time curve of wall motion indicated the retrorse motion of infarcted myocardium in MI group. The peak velocity of wall motion were significantly decreased in each segment compared with Sham group （P〈0.001）, and time to peak of MI group were markedly delayed （P〈0.01）. Conclusion STI provides a new and precise method for evaluation of regional wall motion abnormality after MI in mice.

关 键 词：斑点追踪 心肌梗死 小鼠 超声心动图 

分 类 号：R542.22[医药卫生—心血管疾病] R540.45[医药卫生—内科学]