多普勒组织成像技术与体视学对猪急性心肌梗死动态变化的定量分析

目的：应用多普勒组织成像（DTI）技术与体视学技术对猪急性心肌梗死动态变化进行对照定量分析。方法：10头开胸的猪结扎左冠状动脉前降支（LAD），于结扎后2min,20min,90min,180min,用DTI技术测定左室前壁，后壁收缩期运动速度（Vs)，舒张早，晚期运动速度（VE,VA)，用组织化学染色法分别从心尖，前壁，后壁中部各取材5块，石蜡包埋4um，连续切片，用真彩色图像体视学分析系统对病变进行定量分析。结果：LAD结扎后DTI－二维显示，2min,20min时前壁室壁变薄，色彩暗淡；随时间延长着色异常或色彩缺失，频谱检测Vs,SE随时间延长明显降低（P＜0．01），但90min,180min时无显著差异，组织化学及体视学分析心肌细胞坏死随时间延长逐渐加重，而90min,180min后则心尖部坏死最为严重。结论：DTI技术与体视学对照分析，能提供急性心肌缺血，心肌梗死发生后在不同时间内心肌细胞坏死的动态变化规律，为临床早期评价局部心肌缺血及功能异常提供可靠依据。

Quantitative Analysis on Dynamic Changes of Acute Myocardial Infarction with Doppler Tissue Imaging and Stereology in Experimental Pigs

Objective:To quantitatively analyse the dynamic changes of acute myocardial infarction (AMI) in experimental pigs with Doppler tissue imaging (DTI) and stereology.Methods:The left anterior descending coronary artery (LAD ) of 10 thoracotomied pigs. was ligated.Two, 20, 90 and 180 min, after ligation we determined the systolic velocities (V S), early and late diastolic velocities (V E, V A) of left ventricular anterior and posterior walls. Histochemical staining was performed on samples from heart apex, anterior walls and posterior middle parts, and quantitatively analyses were performed with stereology.Results:The results of DTI-2 mode showed that the anterior ventricular walls were thin and their colors faint after 2 and 20 min ligature,and showed abnormal colors or colors lostd with the time prolonged. Frequency spectrum showed that V S and V E significantly decreased with the time prolonged (P<0.01), but had no difference between 90 and 180 min. Histochemistry and stereology showed that the necrosis of myocytes as gravated with the time prolonged, necrosis in heart apex was the severest after 90 and 180 min ( P <0.01).Conclusions:Comparative analysis with DTI and stereology can provide the rule of the dynamic changes in the necrosis of myocytes during different time after AMI; and can provide the theory accordant with clinical evaluating local myocytic ischemia and abnormal function.