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).
14. Mitral regurgitation is where blood leaks back through the mitral valve in the heart as the valve does not close properly. This increases the pressure in the left atrium and in the blood vessels coming from the lungs. This may lead to various problems and symptoms, depending on the severity of the leak.