Head and neck lymphedema can be caused by surgery or radiation therapy for tongue or throat cancer. It may also occur in the lower limbs or groin after surgery for colon, ovarian or uterine cancer, in which removal of lymph nodes or radiation therapy is required.
1 Heart attack. A heart attack can damage the area of the heart muscle that supports the mitral valve, affecting the function of the valve. If the damage is extensive enough, a heart attack can cause sudden and severe mitral valve regurgitation.  Abnormality of the heart muscle (cardiomyopathy).
In mitral regurgitation the valve does not close properly. This causes blood to leak back (regurgitate) into the left atrium when the left ventricle contracts. Basically, the more open the valve remains, the more blood regurgitates, the more severe the problem.n mitral regurgitation the valve does not close properly. This causes blood to leak back (regurgitate) into the left atrium when the left ventricle contracts. Basically, the more open the valve remains, the more blood regurgitates, the more severe the problem.