Mitral stenosis (MS is a narrowing or blockage of the opening of the mitral vale which separates the upper and lower chambers of the left side of the heart. MS prevents the valve from opening properly and blocks flow of blood from the left atrium to the left ventricle. As the valve area becomes smaller, less blood flows forward to the body, the atrium enlarges as pressure builds and blood may flow back to the lungs.
It is most common in those who have had rheumatic fever. It may be also present at birth or can occur with calcium deposits that accumulate over years.
Symptoms usually develop between the ages of 20 and 50 and often first appear with exercise, stress, or infection. The symptoms may include:
- Difficulty breathing (during or after exercise, when lying flat, at night)
- Cough or blood in phlegm
- Fatigue, especially during times of increased activity
- Frequent respiratory infections, such as bronchitis
- Heart palpitations - sensations of a rapid, fluttering heartbeat
- Chest discomfort or pain
- Swelling of feet or ankles
Mitral stenosis cannot be prevented, but complications can be prevented. The most effective way to prevent mitral valve stenosis is to prevent its most common cause, rheumatic fever. You an do this by making sure you and your children see your doctor when you have a sore throat. Untreated strep throat can develop into rheumatic fever.
- Strep infections should be treated promptly to prevent rheumatic fever.
- Any dental work, including cleaning, and any invasive procedure, such as a colonoscopy, can introduce bacteria into the bloodstream. These bacteria can infect a damaged mitral valve.
- Anticoagulation medication (blood thinners) may be recommended to prevent blood clots in the brain and extremities.
How it is Diagnosed:
A murmur may be noted when listening to the lungs with a stethoscope. Blood pressure is usually normal. An irregular heartbeat may be found or lung congestion noted. A narrowing or obstruction of the valve or enlargement of the atrium may show on tests such as an:
- A transesophageal echocardiogram (TEE)
- Doppler ultrasound
- Cardiac catheterization may demonstrate abnormalities
- Electrocardiogram (ECG) or MRI may be abnormal
Treatment depends on the symptoms and condition of the heart and lungs. Persons with mild symptoms or none, may not need any treatment.
For those needing medical treatment, medications used may include diuretics (water pills), nitrates, or beta-blocker. Digoxin may be used with rhythm disturbances such as atrial fibrillation. Anti-coagulation (blood thinners) are used to prevent blood clots from developing.
Some patients may need heart surgery to replace or repair the valve. Surgical repair is called commissurotomy in which a surgeon attempts to separate the fused leaflets.
Valvuloplasty (percutaneous mitral balloon valvotomy) may be considered instead of surgery. With this procedure, a catheter is inserted into a vein (usually a leg) and up into the heart. A balloon on the tip of the catheter is inflated, widening the mitral valve and improving blood flow. This procedure may not work well with severely damaged mitral valves.