There are three types of mitral valve heart disorders or diseases, each with different causes, according to Healthline. Most mitral valve prolapses have no known cause, but connective tissue problems and scoliosis can contribute to this disease. Rheumatic fever causes most cases of mitral valve stenosis. Mitral valve regurgitation has a variety of causes, which include congenital heart defects, heart attack or trauma, notes Mayo Clinic.
Mitral valve prolapse causes some cases of mitral valve regurgitation, according to Mayo Clinic. And just like mitral valve stenosis, rheumatic fever, which is a complication of untreated strep throat, also can cause mitral valve regurgitation. An infection of the heart lining, called endocarditis, or abnormalities in the heart muscle can cause mitral valve regurgitation as well. Overuse of certain prescription drugs and damaged tissue cords that anchor the heart may also cause mitral valve regurgitation. In very rare cases, radiation used to treat cancer in the chest can cause this disease.
Mitral valve regurgitation occurs when a small portion of the blood flows backward into the left atrium, explains Healthline. A mitral valve prolapse arises when part of the valve slips backward into the left atrium, according to WebMD. Mitral valve stenosis occurs when the valve is too stiff and narrow to allow normal blood flow. While many people with these conditions may have no symptoms, they can lead to heart failure or abnormal heart rhythms, cautions Healthline.