Establishment of a Rat Model of Myocardial Infarction and the Post-Infarction Changes in Electrophysiology and Left Ventricular Function / 中国实验动物学报

ABSTRACT

Objective To establish a stable,repeatable and long-lasting rat model of myocardial infarction,and to evaluate the feasibility of monitoring electrophysiological changes and left ventricular function after myocardial infarction by electrocardiography (ECG) and ultrasonic cardiography(UCG). Methods Wistar rats were ligated on the left anterior descending coronary artery after anaesthesia with 10% chloral hydrate and machinery assisted respiration. Then they were monitored by ECG and UCG afer 4,8 and 12 weeks,and were sacrificed and pathologically examined at 12 weeks after operation. Results The rat model of myocardial infarction was established with a survival rate of 83.3% at 72 hours after the operation and 73.3% at 12 weeks after the operation. In the myocardial infarction group,the PR,QRS,QT and QTc intervals were statistically significantly longer than that in the sham operation group. UCG showed that the left ventricular internal diameter at end-diastole (LVIDd) and the left ventricular internal diameter at end-systole (LVIDs) were statiscally significantly higher in the infarction group,and the ejection fraction (EF) and fractional shortening (FS) significantly lower than those in the sham operation group. Long-lasting pathological changes can be seen in the tissues at 12 weeks after operation. Conclusions The method used in the present study is an simple,less injurious and highly successful technique,and the changes in electrophysiology and left ventricular function can be well monitored by ECG and UCG at different times during this period.