Electrocardiographic characterization of rhesus monkey model of ischemic myocardial infarction induced by left anterior descending artery ligation.

Myocardial infarction is a leading cause for morbidity and mortality in the modern society. Rhesus monkeys are excellent animal models for experimental and translational studies of cardiovascular diseases in humans. However, some detailed characterizations of cardiovascular disease, such as myocardial infarction, in Rhesus monkeys have not been available. The present study was undertaken to examine the progressive electrocardiographic changes in Rhesus monkeys after left anterior descending (LAD) artery ligation. Male Rhesus monkeys, aged 2-3 years and weighed 4.5-6.0 kg, were subjected to LAD ligation along with sham-operated controls. At 1 week, 1 month, and 6 months after the LAD ligation, ECG recording was performed to detect the progressive changes in ECG. In addition, cardiac magnetic resonance imaging (MRI) and echocardiography were applied to detect the myocardial infarction induced by LAD ligation, and histopathological examination was performed at the end of the experiment to measure the morphological changes. The results showed that QRS and ST-T changed significantly within 1 month after LAD ligation, but recovered to normal at the end of the experiment. The most significant change was a progressive QTc prolongation, which occurred corresponding to the development of myocardial infarction. Both cardiac MRI and echocardiography detected the myocardial infarction that was confirmed by the histopathological examination. This detailed characterization of ECG changes along with the development of myocardial infarction induced by LAD ligation thus demonstrated that the Rhesus monkey model of ischemic myocardial infarction would be an excellent surrogate for human myocardial infarction. This model would also provide an excellent tool for drug discovery and development for cardiac disease.