Role of Renin-Angiotensin system in the development of ischemic mitral regurgitation

点击翻译按钮获取中文摘要

Ischemic mitral regurgitation (MR) is an independent factor to worsen patients prognosis after the development of acute myocardial infarction. Outward displacement of papillary muscles due to left ventricular remodeling is the main cause of the ischemic MR. Renin-Angiotensin system (RAS) plays a central role in the genesis of left ventricular remodeling following myocardial infarction. Therefore, activation of RAS system may play an essential role in the genesis of ischemic MR, however, the role of RAS on the development of ischemic MR remains uninvestigated.We hypothesized that development of ischemic MR can be attenuated by the absence of RAS activation due to gene abnormality. We produced acute myocardial infarction (AMI) with a similar size by ligation of left anterior descending artery in wild mouse as well as in Angiotensin II type 1A knocked out mouse. The LV dilatation was significantly greater in the wild compared to knocked out mouse. Ischemic MR was observed only in wild mouse (p<0.05). These suggest that RAS plays a central role in the genesis of ischemic MR after the development of AMI.