Mitral Valve Diseases
The diseases that affect mitral valve are mitral stenosis or narrowing of the valve and mitral valve prolapse.
The mitral valve or the bicuspid valve or left atrioventricular valve lies in the heart between the left atrium and the left ventricle. The closing of the mitral valve and the tricuspid valve constitutes the first heart sound (S1). It is not the valve closure itself which produces the sound but the sudden cessation of blood flow, when the mitral and tricuspid valves close. The diseases that affect mitral valve are mitral stenosis or narrowing of the valve, and mitral valve prolapse which is caused by excess of connective tissue.
Mitral stenosis is caused by rheumatic heart disease. An uncommon cause for mitral stenosis is calcification of the mitral valve leaflets which is a form of congenital heart disease. Other causes may be, infective endocarditis where the vegetation may favor increase risk of stenosis, mitral annular calcification, endomyocardial fibroelastosis, malignant carcinoid syndrome, systemic lupus erythematosus, whipple disease, fabry disease, and rheumatoid arthritis, hurler’ disease, hunter’s disease and myloidosis.
Thickened mitral valve means reduced mitral valve area below 2 Sq cm causes impediment to the flow of blood into the left ventricle. This creates a pressure gradient across the mitral valve resulting in increase in heart rate or cardiac output. It may also lead to atrial fibrillation, a condition marked by abnormal heart rhythm, heart palpitations, fainting, shortness of breath, and chest pain.
RISK FACTORS & COMPLICATIONS
The risk factors and complications are evident as mitral valve prolapse and regurgitation. Mitral valve regurgitation is a condition where the valve leaks blood back into the left atrium. The complications are also evident as heart rhythm problems (arrhythmias), and heart valve infection (endocarditis).
TESTS AND DIAGNOSIS
The doctor listens to the heart by using a stethoscope. The existence of mitral valve diseases would mean hearing of clicking sounds or heart murmur. These sounds occur due to blood leaking backward through the mitral valve. An echocardiogram is also advised by the doctor. The echocardiogram is a non-invasive process that evaluates the condition of the heart, creates images of the heart and its structures.
Chest X-ray and Electrocardiogram also help the doctor in the diagnosis of mitral valve diseases. Any irregularities in the heart’s rhythm and structure are identified by the doctor. Under certain conditions, the stress test is advised by the doctor. Stress test includes exercise or medications to increase the heart rate. The heart is made to work harder. Any condition of mitral valve regurgitation is sure to limit one’s ability to exercise.
TREATMENTS AND DRUGS
When significant amount of blood is leaking through the mitral valve, the consulting doctor may recommend medications and surgery. Medications are directed at correcting the heartbeat, relax the blood vessels and improve the blood flow. Diuretics are prescribed to drain water/fluid from the lungs. The risk of blood clots is reduced by appropriate medications.
In most cases of mitral valve prolapse or other diseases, surgical treatment may not be necessary. However in conditions of mitral valve regurgitation, there are more chances for heart failure. The doctor recommends a surgery which involves replacing or repairing the mitral valve. The surgical procedures for mitral valve replacement or repair may be open heart surgery or minimally invasive surgery. The latter is considered as more patient friendly, with promising scope for lesser blood loss and quicker recovery time.