Mitral Stenosis
Mitral stenosis is a narrowing of the heart's mitral valve. This abnormal valve doesn't open properly, obstructing blood flow into the main pumping chamber of your heart (left ventricle). Mitral stenosis isn't as widespread as it once was because the most common cause, rheumatic fever, is rare in Canada. However, rheumatic fever remains a problem in developing nations.
Causes
- Rheumatic fever. Most cases of mitral valve stenosis are caused by rheumatic fever, which can scar the mitral valve. This fever results from an untreated strep infection, most often strep throat. Many people with mitral valve stenosis are unaware that they had rheumatic fever.
- Calcium deposits. As you age, calcium deposits can build up around the mitral valve, and occasionally cause mitral stenosis.
- History of radiation therapy to the chest
- Other causes. In rare cases, babies are born with a narrowed mitral valve (congenital defect) that causes problems over time. In rare cases, some autoimmune diseases, such as lupus, may also cause mitral valve stenosis.
Symptoms
Mitral stenosis is a lifelong disease, but symptoms may not happen for many years. When symptoms first appear, they usually are mild. You may only have a few symptoms, even if your mitral valve is very narrow. An early symptom is shortness of breath when you are active. This shortness of breath may seem normal to you.
As mitral stenosis progresses, symptoms may include:
- Shortness of breath, even when you have not been very active or when you are lying down.
- Feeling very tired or weak.
- Palpitations (rapid, fluttering heartbeat)
- Swollen feet or legs
- Chest discomfort or chest pain
- Coughing up blood
- Dizziness or fainting
- Fluid buildup in the lungs
Treatment
A mitral stenosis diagnosis is made after hearing a characteristic heart murmur through a stethoscope placed over the heart or using echocardiography. Treatment depends on how severe the disease and your symptoms are.
Treatments can include:
- Regular checkups and echocardiograms
- Medications to treat complications
- Surgery or other procedures
When to see a doctor
Seek medical attention if you have fatigue or shortness of breath during physical activity, heart palpitations or chest pain. If you have been diagnosed with mitral valve stenosis but haven't had symptoms, ask your doctor about how often you should have follow-up evaluations.
Prevention
The best way to prevent mitral valve stenosis is to prevent its most common cause, rheumatic fever. You can do this by making sure you and your family see your doctor for sore throats. Untreated strep throat infections can develop into rheumatic fever. The good news is that strep throat is now easily treated with antibiotics.