Mitral valve stenosis

Overview

Mitral valve stenosis — sometimes called mitral stenosis — is a narrowing of the valve between the two left heart chambers. The narrowed valve reduces or blocks blood flow into the lower left heart chamber. The lower left heart chamber is the heart's main pumping chamber. It also is called the left ventricle.

Mitral valve stenosis can make you tired and short of breath. Other symptoms may include irregular heartbeats, dizziness, chest pain or coughing up blood. Some people don't notice symptoms.

Mitral valve stenosis can be caused by a complication of strep throat called rheumatic fever. Rheumatic fever is now rare in the United States.

Treatment for mitral valve stenosis may include medicine or mitral valve repair or replacement surgery. Some people only need regular health checkups. Treatment depends on how severe the valve disease is and whether it's getting worse. Untreated, mitral valve stenosis can lead to serious heart complications.

Typical heart and heart with mitral valve stenosis

Symptoms

Mitral valve stenosis usually worsens slowly. You may not have any symptoms, or you may have mild ones for many years. Symptoms of mitral valve stenosis can occur at any age, even during childhood.

Symptoms of mitral valve stenosis include:

  • Shortness of breath, especially with activity or when you lie down.
  • Fatigue, especially during increased activity.
  • Swollen feet or legs.
  • Pounding, skipping or otherwise irregular heartbeats, called arrhythmias.
  • Dizziness or fainting.
  • Fluid buildup in the lungs.
  • Chest discomfort or chest pain.
  • Coughing up blood.

Mitral valve stenosis symptoms may appear or get worse when the heart rate increases, such as during exercise. Anything that puts stress on the body, including pregnancy or infections, may trigger symptoms.

When to see a doctor

Make an appointment with your healthcare professional right away if you have chest pain, a fast, fluttering or pounding heartbeat, or shortness of breath during activity. Your healthcare professional may tell you to see a doctor trained in heart diseases, called a cardiologist.

If you have been diagnosed with mitral valve stenosis but haven't had symptoms, ask your healthcare team how often to have follow-up exams.

Causes

To understand the causes of mitral valve disease, it may be helpful to know how the heart works.

The mitral valve is one of four valves in the heart that keep blood flowing in the right direction. Each valve has flaps, called leaflets, that open and close once during each heartbeat. If a valve doesn't open or close properly, less blood may flow through the heart to the body.

In mitral valve stenosis, the valve opening narrows. The heart now must work harder to force blood through the smaller valve opening. Blood flow between the upper left and lower left heart chambers may decrease.

Causes of mitral valve stenosis include:

  • Rheumatic fever. This complication of strep throat is the most common cause of mitral valve stenosis. When rheumatic fever damages the mitral valve, the condition is called rheumatic mitral valve disease. Symptoms may not be seen until years to decades after rheumatic fever.
  • Calcium deposits. As you age, calcium deposits can build up around the mitral valve. This can cause narrowing of the structures that support the mitral valve flaps. The condition is called mitral annular calcification, or MAC for short. Severe MAC can cause mitral stenosis symptoms. It's difficult to treat even with surgery. People with calcium around the mitral valve often have similar problems with the heart's aortic valve.
  • Radiation therapy. This is a treatment for certain types of cancer. Radiation to the chest area can sometimes cause the mitral valve to thicken and harden. The heart valve damage typically occurs 20 to 30 years after radiation therapy.
  • Heart condition present at birth, called a congenital heart defect. Rarely, some babies are born with a narrowed mitral valve.
  • Other health conditions. Lupus and other autoimmune conditions may rarely cause mitral valve stenosis.
Chambers and valves of the heart

Risk factors

Risk factors for mitral valve stenosis include:

  • Untreated strep infections. A history of untreated strep throat or rheumatic fever increases the risk of mitral valve stenosis. However, rheumatic fever is rare in the United States. But it's still a problem in developing nations.
  • Aging. Older adults are at increased risk of calcium buildup around the mitral valve.
  • Radiation therapy. Radiation causes changes in the mitral valve shape and structure. Rarely, people who receive radiation therapy to the chest area for certain types of cancer may develop mitral valve stenosis.
  • Illicit drug use. MDMA, short for methylenedioxymethamphetamine and commonly called molly or ecstasy, increases the risk of mitral valve disease.
  • Use of certain medicines. Some migraine medicines have an ingredient called ergot alkaloids. Ergotamine (Ergomar) is an example. Ergot alkaloids may rarely cause heart valve scarring that leads to mitral stenosis. Older weight-loss medicines that contained fenfluramine or dexfenfluramine also are linked to heart valve disease and other heart problems. Fen-phen is an example. It's no longer sold in the United States.

Complications

Mitral valve stenosis that is not treated can lead to complications such as:

  • Irregular heartbeats. Irregular heartbeats are called arrhythmias. Mitral valve stenosis may cause an irregular and chaotic heart rhythm called atrial fibrillation. It's commonly known as AFib. AFib is a common complication of mitral stenosis. The risk increases with age and more-severe stenosis.
  • Blood clots. Irregular heartbeats linked to mitral valve stenosis can cause blood clots to form in the heart. If a blood clot from the heart travels to the brain, a stroke can occur.
  • High blood pressure in the lung arteries. The medical name for this condition is pulmonary hypertension. It can happen if a narrowed mitral valve slows or blocks blood flow. Decreased blood flow raises pressure in the lung arteries. The heart must work harder to pump blood through the lungs.
  • Right-sided heart failure. Changes in blood flow and high pressure in the lung arteries put a strain on the heart. The heart must work harder to pump blood to the chambers on the right side of the heart. The extra effort eventually causes the heart muscle to become weak and fail.

Prevention

Rheumatic fever is the most common cause of mitral valve stenosis. So the best way to prevent mitral valve stenosis is to prevent rheumatic fever. You can do this by making sure you and your children see a healthcare professional for sore throats. Untreated strep throat infections can develop into rheumatic fever. Strep throat is usually easily treated with antibiotics.

Diagnosis

To diagnosis mitral valve stenosis, your healthcare professional examines you and asks questions about your symptoms and medical history. You also may be asked about your family's medical history.

The healthcare professional listens to your heart and lungs with a device called a stethoscope. Mitral valve stenosis often causes an irregular heart sound due to the narrowed opening. This sound is called a heart murmur. Mitral valve stenosis also can cause fluid buildup in the lungs.

If you have symptoms of mitral valve stenosis, tests are done to examine the heart.

Tests

Imaging tests are done to check your heart health. Some can confirm mitral valve stenosis and help find the cause. Test results help decide treatment.

Tests may include:

  • Echocardiogram. An echocardiogram can confirm mitral stenosis. Sound waves create images of the beating heart. The test can show areas of poor blood flow and heart valve changes. It also can help find out the severity of mitral valve stenosis.

    If you have very severe mitral stenosis, you should get an echocardiogram every year. Those with less severe mitral stenosis need an echocardiogram about every 3 to 5 years. Ask your healthcare professional how often you need one.

  • Electrocardiogram (ECG or EKG). This quick and painless test shows how the heart is beating. Sticky patches with sensors on them go on the chest and sometimes the arms and legs. Wires connect the electrodes to a computer, which displays or prints the test results.
  • Chest X-ray. A chest X-ray shows the condition of the heart and lungs. It can tell whether the heart is enlarged, which can be a sign of certain types of heart valve disease.
  • Exercise stress tests. These tests often involve walking on a treadmill or riding a stationary bike while the heart's activity is checked. Exercise tests help show how the heart responds to physical activity and whether valve disease symptoms occur during exercise. If you can't exercise, you might get medicines that affect the heart like exercise does.
  • Cardiac CT. This test combines several X-ray images to make a detailed view of the heart and the heart valves. A cardiac CT is commonly done to see mitral stenosis that isn't caused by rheumatic fever.
  • Cardiac MRI. This test uses magnetic fields and radio waves to create detailed images of the heart. A cardiac MRI might be done to determine the severity of mitral valve stenosis.
  • Cardiac catheterization. This test isn't often used to diagnose mitral stenosis, but it may be done when other tests aren't able to diagnose the condition or determine its severity. A flexible tube called a catheter is inserted in a blood vessel, usually in the groin or wrist. It's guided to the heart. Dye flows through the catheter to arteries in the heart. The dye helps the arteries show up more clearly on X-ray images and video.

Treatment

Staging

After testing confirms a diagnosis of mitral or other heart valve disease, your healthcare professional may tell you the stage of disease. Staging helps determine the most appropriate treatment.

The stage of heart valve disease depends on many things, including symptoms, disease severity, the structure of the valve or valves, and blood flow through the heart and lungs.

Heart valve disease is staged into four basic groups:

  • Stage A: At risk. Risk factors for heart valve disease are present.
  • Stage B: Progressive. Valve disease is mild or moderate. There are no heart valve symptoms.
  • Stage C: Asymptomatic severe. There are no heart valve symptoms, but the valve disease is severe.
  • Stage D: Symptomatic severe. Heart valve disease is severe and is causing symptoms.

Treatment for mitral valve stenosis may include:

  • Medicine.
  • Valve repair or replacement surgery.
  • Open-heart surgery.

If you have mild to moderate mitral valve stenosis with no symptoms, you might not need immediate treatment. Instead, you need regular health checkups to see if your condition gets worse.

A doctor trained in heart disease typically provides care for people with mitral valve stenosis. This type of doctor is called a cardiologist.

Medications

Medicines are used to reduce the symptoms of mitral valve stenosis. They may include:

  • Diuretics, also called water pills, to reduce fluid buildup in the lungs or other areas of the body.
  • Blood thinners, called anticoagulants, to help prevent blood clots if you have an irregular heartbeat called atrial fibrillation (AFib).
  • Beta blockers, calcium channel blockers or other heart medicines to slow the heart rate.
  • Medicines for irregular heartbeats. These medicines are called antiarrhythmics.
  • Antibiotics to prevent a return of rheumatic fever if that's what damaged the mitral valve.

Surgery or other procedures

A diseased or damaged mitral valve might eventually need to be repaired or replaced, even if you don't have valve disease symptoms. If you need surgery for another heart condition, a surgeon might do mitral valve repair or replacement at the same time as that treatment.

Together you and your healthcare team talk about the best treatment for you. Surgeries and procedures for mitral valve stenosis may include:

  • Balloon valvuloplasty. This treatment is done to repair a mitral valve with a narrowed opening. It's also called mitral balloon valvotomy, percutaneous mitral balloon commissurotomy or percutaneous transvenous mitral commissurotomy.

    Balloon valvuloplasty uses a flexible tube called a catheter and a tiny balloon. The doctor inserts the balloon-tipped catheter into an artery, usually in the groin. It's guided to the mitral valve. The balloon is inflated, widening the mitral valve opening. The balloon is deflated. Then the catheter and balloon are removed.

    Valvuloplasty might be done even if you don't have symptoms. But not everyone with mitral valve stenosis is a candidate for the treatment. Ask your healthcare professional if it's an option for you.

  • Open-heart surgery to repair the valve. If a catheter procedure isn't an option, an open-heart surgery called open valvotomy may be done. The surgery also may be called surgical commissurotomy. It removes calcium deposits and other scar tissue blocking the mitral valve opening. The heart must be stopped to prevent bleeding in the chest area during this surgery. A heart-lung machine temporarily takes over the heart's job. The procedure may need to be repeated if mitral valve stenosis returns.
  • Mitral valve replacement. If the mitral valve can't be repaired, surgery may be done to replace the damaged valve. The damaged valve is replaced with a mechanical one or a valve made from cow, pig or human heart tissue. A valve made from animal or human tissue is called a biological tissue valve.

    Biological tissue valves break down over time and may need to be replaced. People with mechanical valves need lifelong blood thinners to prevent blood clots. Together you and your healthcare professional should talk about the benefits and risks of each type of valve to choose the best option for you.

The outlook for people who have a catheter treatment or surgery for mitral stenosis is generally good. But older age, poor health, and a lot of calcium buildup on or around the valves increase the risk of surgery complications. Long-term pulmonary hypertension may worsen the outlook after valve surgery.

Lifestyle and home remedies

Lifestyle changes can help improve heart health. If you have mitral valve stenosis, try these steps to keep your heart healthy:

  • Eat nutritious foods. Eat a variety of fruits and vegetables, low-fat or fat-free dairy products, poultry, fish, and whole grains. Avoid saturated and trans fat. Use less salt and sugar.
  • Keep a healthy weight. If you are overweight or have obesity, losing weight can help control blood pressure and lower the risk of complications. Ask your healthcare professional what weight is best for you.
  • Don't smoke or use tobacco. Smoking is a major risk factor for heart disease. If you smoke and can't quit, talk to your care team about programs or treatments that can help.
  • Limit alcohol. If you choose to drink alcohol, do so in moderation. For healthy adults, that means up to one drink a day for women and up to two drinks a day for men.
  • Ask about exercise. How long and hard you're able to exercise may depend on the severity of mitral valve stenosis and the intensity of exercise. Talk to your healthcare team about the amount and type of exercise that's best for you, especially if you're considering competitive sports. People with severe mitral stenosis should not do competitive sports.
  • Get regular health checkups. Regular health checkups are important if you have mitral valve stenosis. You should have an echocardiogram at least every year. If you frequently feel your heart pounding or beating fast, get medical help. Fast heart rhythms that aren't treated can quickly get worse in people with mitral valve stenosis.
  • Manage stress. Find ways to help manage stress, such as through relaxation activities, meditation, physical activity, and spending time with family and friends.
  • Get good sleep. Poor sleep may increase the risk of heart disease and other chronic conditions. Adults should aim to get 7 to 9 hours of sleep daily. Go to bed and wake at the same time every day, including on weekends. If you have trouble sleeping, talk to your healthcare professional about strategies that might help.

Pregnancy

If you have mitral valve stenosis and want to become pregnant, talk with a healthcare professional first. Pregnancy causes the heart to work harder. How a heart with mitral valve stenosis handles the extra work depends on how narrow the valve is and how well the heart pumps. If you are pregnant and have mitral valve stenosis, your care team should closely check you during pregnancy. A healthcare professional can explain which medicines are safe to take during pregnancy. You and your healthcare professional also can discuss whether you need heart valve treatment before pregnancy.

Preparing for an appointment

If you have mitral valve stenosis, you may see a doctor trained in heart diseases, called a cardiologist.

Here's some information to help you prepare for your appointment.

What you can do

  • Write down your symptoms and when they started.
  • List important medical information, including other health conditions you have and any family history of heart disease.
  • List all the medicines you take, including those bought without a prescription. Include dosages.
  • Take someone with you to the appointment, if possible. Someone who goes along may help you better remember any information.
  • Write down the questions to ask your care healthcare professional.

Questions to ask your healthcare professional at the first appointment include:

  • What is the likely cause of my symptoms?
  • Are there other possible causes for these symptoms?
  • What tests do I need?
  • Should I see a specialist?

Questions to ask if you are referred to a cardiologist include:

  • What is my diagnosis?
  • What treatment do you recommend?
  • What are the possible side effects of the medicines you recommend?
  • What will my recovery be like from the treatment you recommend?
  • How will you check my health over time?
  • What is my risk of long-term complications from mitral valve stenosis?
  • Do I need to change my exercise routine?
  • What diet and lifestyle changes should I make?
  • I have other health conditions. How can I best manage them together?

It's important for you to understand your condition. Don't hesitate to ask other questions.

What to expect from your doctor

Your healthcare team usually asks many questions, such as:

  • What are your symptoms?
  • When did your symptoms begin?
  • Do you always have symptoms, or do they come and go?
  • Do you have rapid, fluttering or pounding heartbeats?
  • Have you coughed up blood?
  • Does exercise or physical activity make your symptoms worse?
  • Do you have any family members with heart valve disease?
  • Have you had rheumatic fever?
  • Are you being treated or have you recently been treated for any other health conditions?
  • Do you or did you smoke? How much? When did you quit?
  • Do you use alcohol or caffeine? How much?
  • Are you planning to become pregnant in the future?

What you can do in the meantime

While you wait for your appointment, find out if any of your family members have heart disease. The symptoms of mitral valve stenosis are similar to other heart conditions. Some of these conditions can occur in families. Knowing about your family's health history helps your healthcare team decide your diagnosis and treatment.

If exercise makes your symptoms worse, do not exercise until you see your healthcare professional.


Content From Mayo Clinic Updated: 09/03/2024
© 1998-2024 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. Terms of Use