解剖M型超声心动图评价介入栓塞法猪急性心肌梗死模型左心结构与局部功能

摘要

Objective To assess the structure and the local function of left ventricular ( LV ) after acute myocardium infarction ( AMI ) in pigs by anatomic M-mode echocardiography ( AME ). Methods The coronary arteries of pigs were obstructed by thread to prepare model AMI. AME was performed before and one day after the procedure. The parameters were detected and computed including diastolic rnand systolic ventricular wall thickness ( Td, Ts ), the wall thickening fraction ( ΔT％ ),the wall motion amplitudes ( Am ) of LV 16 segments, left ventricular end systolic diameter( LVEDs ), left ventricular end diastolic diameter ( LVEDd ), and ejection fraction ( LVEF ). The lower limit value ( 6 mm ) of 95％ confidence interval of the AM difference in healthy pigs was used as the standard for diagnosis of abnormal segments ( infarcted segments ). The segments diagnosed by AME as infarcted ones were compared with the results by histopathological examination. Results Compared with the parameters measured before the operation in the corresponding segments, Ts, Td, ΔT％ and Am decreased in the infarcted segments ( P ＜0. 05 ) after operation. After the AMI, there was a difference between normal segments and the infracted segments. Ts, Td, ΔT％ and Am decreased in the infracted segments ( P ＜ 0. 01 ). Compared with those parameters measured before AMI, LVEDs expanded ( P ＜0. 05 ) and LVEF decreased ( P ＜ 0. 05 ). Compared with the histopathological results, the detecting sensibility, specificity and accuracy for the diagnosis of infarcted segments by AME were 80. 0％ , 91. 4％ and 89. 6％ , respectively. Conclusion AME can quantitatively assess the structure and local function of left ventricular after AMI in pigs.%目的 应用解剖M型超声心动图(AME)对猪急性心肌梗死(AMI) 模型左心室结构、局部功能进行评价.方法 采用经冠状动脉丝线堵塞法制作小型猪AMI动物模型.于术前、术后1 d检测并计算左心室16节段室壁收缩末期厚度(Ts)、舒张末期厚度(Td)、室壁收缩期增厚率(△T%)及运动幅度(Am),左心室收缩与舒张末期内径(LVEDs,LVEDd)、射血分数(LVEF).根据健康小型猪Am的95%可信区间下限值(6 mm)判定室壁运动异常节段[心肌缺血(梗死)节段],并将AME确定的心肌梗死节段与组织病理学结果进行对照.结果 与术前相对应的节段相比,术后心肌梗死节段Ts、Td、△T%及Am测值下降(P＜0.05);与术后非心肌梗死节段相比,术后心肌梗死节段Ts、Td、△T%及Am测值下降(P＜0.01).与术前相比,术后LVEDs增大,LVEF降低(P＜0.05).与组织病理学结果对照分析,AME对心肌缺血(梗死)节段判定的敏感度为80.0%,特异度为91.4%,准确度为89.6%.结论 AME能够对猪AMI后左心室结构及局部功能进行定量分析.