·The Mitral valve (also known as the bicuspid valve or left atrioventricular valve) is a dual flap valve in the heart that lies between the left atrium and the left ventricle, which is closed when left ventricle contracts and prevent blood regurgitation from left ventricle to left atrium.

·Mitral Regurgitation (MR) is a disorder of the heart in which the Mitral valve does not close properly when the heart pumps out blood. MR is the abnormal leaking of blood from the left ventricle through the Mitral valve, and into the left atrium, when the left ventricle contracts. Functional MR (also called secondary MR) is caused by enlargement of the heart due to heart attack or heart failure.

·MR is the most frequent valve disease in U.S. Over 4 million people have significant MR, with an annual incidence of 250,000. Approximately 50,000 of these patients undergo surgery each year in U.S. Prevalence and incidence are similar in EU, where it's the second most common type of heart valve disease.

·LV (Left ventricular) remodeling (also called as enlargement) can be the result of a number of conditions including pressure overload (due to hypertension and aortic stenosis), volume overload (due to aortic regurgitation, mitral regurgitation) and wall abnormalities (like left ventricular aneurysm and hypertrophic cardiomyopathy). And enlarged LV consequently can make MR worse and cause Heart Failure with Reduced Ejection Fraction (HFrEF).

·LV remodeling and MR are circularly related in cause-and-effect. And HFrEF patients which is related with LV remodeling are 10 times much more than Functional MR (FMR) patients.

·In addition to conventional open surgery for Mitral valve repair or replacement, recently transcatheter mitral valve repair (TMVr) has been introduced. However, the existing TMVr is effective on specific functional mitral regurgitation (FMR) patients and new solution for various FMR and LV remodeling is needed.

·Percutaneous mitral valve (MV) repair attracts much attention in interventional cardiology because it has shown excellent efficacy for improving the quality of life of heart failure patients who have significant mitral regurgitation.