 Hello, I am Dr. Devananda, Head of the Department of Cardiac Surgery at Manipal Hospitals. I have been practicing cardiac surgery for the last 18 years. Mitral regurgitation in essence means leaking mitral valve. Now, there are several reasons which can produce this. One of the common thing again in our country is rheumatic heart problem, which affects the valve and mitral valve can leak. Now, second important cause which is increasing even in our population is mitral leak because of degenerative pathology of the mitral valve, which means the valve substrate, the material which makes the valve is weak, which eventually fails and produces the leakage. Another cause is whatever that affects the mechanism of this valve, like the cardotendin which holds the mitral valve to the ventricular muscle or diseases like ischemic heart disease. In layman terms, we call it as heart attacks, which cuts off the blood supply to some part of the heart muscle. That part of the muscle does not function well and if that happens to support the mitral valve, the mitral valve can leak. So, the causes can be congenital from birth or it can be secondary to an infection like rheumatic heart disease. It can be degenerative cause where the substrate of the valve itself is abnormal or it could be ischemic where there is blockage of one of the coronary arteries leading to heart attack thereby causing dysfunction of the ventricle. There is one other form which is quite rare that is cardiomyopathies where the entire heart muscle by itself will become weak over a period of time making the frame of the valve so called annulus to dilate or enlarge and thereby making this valve incompetent.