What is mitral valve stenosis?
Mitral stenosis is the narrowing of the mitral valve, which is the heart valve that controls the flow of blood from the heart’s left atrium to the left ventricle. Because those with mitral valve stenosis have a narrowed mitral valve, blood flow to the left ventricle — the heart’s main pumping chamber — is decreased or, in severe cases, is blocked entirely. This then requires the heart to work harder to compensate for a lack of blood flow, risking heart failure.
The mitral valve is one of the heart’s four main heart valves. These heart valves are responsible for controlling the direction of blood through the valves to the heart’s chambers for optimal pumping. When your mitral valve isn’t functioning correctly, blood and pressure build up, causing the left atrium to enlarge and fluid to enter the lungs.
The mitral valve also has flaps (also called leaflets or cusps) that open and close once per beat of the heart. When these flaps do not properly close, they leak blood back into the left atrium. This is another form of mitral valve disease called mitral regurgitation.
Mitral valve stenosis symptoms
Mitral valve stenosis progresses slowly over time. You may not notice symptoms for years. Symptoms can develop at any age, even in childhood. They may include:
- Shortness of breath: you may have a hard time breathing, especially after being active or when you lie down.
- Fatigue: you may tire easily during increased physical activity.
- Swollen ankles and feet: swelling may occur when blood flow is disturbed.
- Heart palpitations: you may notice a rapid, fluttering heartbeat.
- Fainting or dizziness: you may feel lightheaded or even lose consciousness, especially during activity.
- Coughing up blood: if you see signs of blood when you cough, see your doctor.
- Chest pain: you might feel discomfort in your lungs and chest.
- Irregular heart rhythm: because of blood flow disruption, your doctor my notice an irregular heartbeat (arrhythmia).
- Heart murmur: irregular sounds that may be discovered during a cardiac examination.
What causes mitral valve stenosis?
The most common cause of mitral stenosis is rheumatic fever — a complication of strep throat. This infection can scar the mitral valve, causing it to thicken with scar tissue and narrow. While rheumatic fever is now rare in the United States, it is still common in developing countries.
Other causes of mitral stenosis are age (calcium deposits build up on the valve over time), radiation to the chest, congenital heart defects and autoimmune diseases like lupus.
What are the risk factors for mitral valve stenosis?
There are a few risk factors associated with an increased chance of developing mitral stenosis. Some of these factors are within a person’s ability to change or prevent (lifestyle risks) and some are out of a person’s control (genetic or demographic risks). Things that may increase your risk of mitral valve stenosis are:
- Untreated strep throat or infections caused by strep throat (rheumatic fever)
- Radiation therapy to the chest, such as for cancer treatment
- Use of certain illegal drugs, like MDMA (ecstasy)
- Certain medications containing ergot alkaloids
- Aging, which often sees an increase in calcium deposits that thicken the valve
Congenital heart disease that may impact the structure or function of the mitral valve
Diagnosing mitral valve stenosis
Mitral valve stenosis is often diagnosed based on the appearance of related symptoms, like shortness of breath and heart palpitations. However, your doctor may detect signs of mitral valve stenosis during an examination. These signs include:
- Heart murmur
- Fluid buildup in the lungs
- Irregular heart rhythm, such as atrial fibrillation (AFib)
If you have symptoms associated with mitral stenosis, your doctor will use echocardiography and cardiovascular imaging techniques including:
- Transthoracic echocardiogram (TTE)
- Transesophageal echocardiogram (TEE)
- Electrocardiogram (ECG)
- Chest X-ray
Mitral valve stenosis treatment at Penn Medicine
While no medications can correct mitral valve stenosis, your doctor may prescribe medication to address your symptoms. If your cardiologist determines that you need a mitral valve replacement or repair, Penn offers both surgical and nonsurgical options, including:
- Mitral valve repair and replacement surgery, which is performed as traditional open-chest surgery or minimally invasive heart surgery, depending on your health and diagnosis. Whenever possible, our academic surgeons use robotic surgery for mitral valve replacement.
- Transcatheter mitral valve replacement (TMVR), a nonsurgical option for valve replacement if a previously replaced mitral valve is narrowed.
- Balloon valvuloplasty, a catheter-based treatment option for rheumatic mitral stenosis that uses an expanded balloon to open a narrowed mitral valve.
Heart Valve Disease at Penn Medicine is supported by some of the most recognized heart valve surgeons and cardiologists in the nation. Our multidisciplinary care team includes experts from our Interventional Cardiology and Heart Surgery divisions that have had decades of experience using the most precise and advanced treatments for mitral valve disease.