What is mitral stenosis?

Mitral stenosis, or mitral valve stenosis, is a narrowing of the mitral valve. One of your heart’s four valves, the mitral valve controls blood flow between the left atrium (upper chamber) and left ventricle (lower chamber) of the heart. Stenosis can restrict the amount of blood flowing through the heart to the rest of the body.

Your mitral valve normally opens to allow blood to flow, then closes to prevent it from flowing back. When the mitral valve narrows, blood flow is limited. As a result, blood can get trapped in your left atrium, putting pressure on the blood vessels that bring oxygen-rich blood from your lungs to your heart. Over time, this pressure can cause your heart’s upper chambers to get larger and allow fluid to build up in your lungs.

Mitral stenosis symptoms

Mitral stenosis typically does not cause symptoms unless it is severe. You may not know you have it until your doctor hears a heart murmur when listening to your heart at a routine check-up.

However, you might experience symptoms when your heart is under stress, for example, during pregnancy or an infection.

Symptoms of mitral stenosis may include:

  • Breathing difficulties during or after activity or when lying down
  • Chest pain or discomfort with activity that radiates to the arm, neck, jaw or other parts of the body
  • Coughing that may be bloody
  • Fainting
  • Feeling dizzy or lightheaded
  • Feeling very tired
  • Flushed cheeks that appear purple (mitral facies)
  • Frequent respiratory infections
  • Heart palpitations
  • Shortness of breath when resting
  • Swollen ankles or feet

Mitral stenosis can also exist at birth. In babies and children with the condition, symptoms usually appear by age 2 and may include:

  • Coughing
  • Problems gaining weight, possibly due to feeding difficulties
  • Shortness of breath
  • Slowed growth

When to see a doctor

See your doctor if you have symptoms of mitral stenosis, particularly if you have a bloody cough, which could suggest severe narrowing of the valve. Always call 911 if you experience chest pain that radiates to your neck, back or jaw, shortness of breath and dizziness, or lightheadedness, as these could be signs of a heart attack.

Because the condition often causes no symptoms, having regular checkups with your primary care doctor allows them to identify heart murmurs and other signs early.

Causes of mitral stenosis

Mitral stenosis can be caused by a birth defect. The most common cause in adults is rheumatic fever, an infection that can develop after untreated strep throat or other infections. Mitral valve symptoms may not appear until decades after an illness.

Narrowing of the valve can also be caused by a buildup of calcium, which is more common as you get older. Other possible, but less common, causes include:

  • Endocarditis, an infection of the heart and heart valves
  • Radiation treatments to the chest
  • Rheumatoid arthritis
  • Systemic lupus erythematosus
  • Whipple disease
  • Carcinoid, a slow-growing tumor
patient consulting with doctor

Mitral stenosis risk factors

Having a condition linked to mitral stenosis can increase your risk. However, it’s becoming less common in the United States thanks to better infection treatments that have lowered rates of rheumatic fever, the leading risk factor for mitral stenosis.

Mitral stenosis becomes more common with age. Older adults are more likely to have calcium buildup on their valves, and they may have had an infection early in life before the widespread use of antibiotics. Mitral stenosis is also common in parts of the world where antibiotic use is lower than it is in the US.

Additional risk factors include:

  • Genetics: Mitral stenosis may run in families and can be linked to genetics.
  • Sex: Mitral stenosis caused by rheumatic fever is more common in women than men.

Complications

Left untreated, mitral stenosis can lead to serious complications. Reduced blood flow through your valve can mean less oxygen-rich blood is pumped around your body. As blood builds up in your left atrium, this can increase pressure. Blood clots can form, which may break off and travel to other parts of your body.

Possible complications include:

  • Arrhythmias: Problems with the mitral valve can cause atrial fibrillation or atrial flutter.
  • Heart failure: The added strain on the heart may reduce its ability to pump enough blood for the rest of your body, leading to heart failure.
  • Pulmonary edema: As blood builds up in your left atrium, fluid can collect in your lungs. This is called pulmonary edema.
  • Pulmonary hypertension: Pressure buildup can cause high blood pressure in the lungs.
  • Stroke: A blood clot blocking blood flow to your brain can cause an ischemic stroke .

Diagnosing mitral stenosis

The diagnostic process for mitral stenosis often begins when your doctor hears a heart murmur during a physical exam. Many lifestyle factors and conditions can cause a murmur, so they will likely try to determine its cause.

You may need various tests to determine whether you have mitral stenosis or another condition. Your doctor may refer you to a cardiologist.

  • Medical history and exam

    Your doctor will ask about your medical history, your family history and any other health conditions you have. They will listen to your heart with a stethoscope to see if you have a heart murmur. You might be asked to walk around, as exercise can make a murmur louder.

    Your doctor will also perform a physical examination, looking for signs such as bulging veins or swelling in your ankles and feet.

  • Imaging and tests

    Tests and scans give your doctor a better look at your heart and help them determine what’s causing your symptoms. If you have mitral stenosis, scans can help your doctor with mitral stenosis grading. This means using factors such as the mobility and thickness of your valve to assess how severe your condition is.

    Tests and scans may include:

    • Chest X-ray: X-ray images allow your doctor to see your heart and lungs. The images can show structural changes in your heart that indicate mitral stenosis.
    • Echocardiogram: Echocardiograms use sound waves to produce images of your heart. They can show narrowing of your mitral valve and how well blood travels through it.
    • Electrocardiogram: This test measures the electrical activity of your heart. Certain changes in electrical activity can suggest an enlarged atrium, which may be a sign of mitral stenosis. It can also detect if you have developed atrial fibrillation.
    • Cardiac catheterization: If you are diagnosed with mitral stenosis, your doctor may order this test to see how severe it is. For the test, your doctor inserts a thin tube, called a catheter, through a vessel in either your neck or the femoral (thigh) area and measures pressure inside your heart.

Mitral stenosis treatment

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If your doctor diagnoses you with mitral stenosis, they may grade it from 1 to 4. In grade 1, the valve has minimal narrowing and a small amount of calcium buildup. By grade 4, the most severe, the valve has become very thick and calcified.

If your mitral stenosis is mild or does not cause bothersome symptoms, you may not need treatment. Your doctor will usually recommend annual checkups and regular tests to ensure your condition does not get worse, and they may recommend antibiotics before certain dental or medical procedures to prevent an infection like endocarditis from damaging your heart.

For more severe grades of mitral stenosis, your doctor may recommend medication, nonsurgical procedures or surgery.

Medication

Your doctor may prescribe various medications, depending on your symptoms and how severe they are. Medication can reduce your risk of complications, such as blood clots, which can cause heart attacks or strokes. Always tell your doctor if you experience any side effects.

Medications to treat symptoms include:

  • Antiarrhythmic medicine: These can treat abnormal heart rhythms caused by mitral stenosis.
  • Beta blockers: These drugs slow your heart rate and reduce blood pressure, lowering your risk of heart problems.
  • Blood thinners: These prevent blood clots that could cause a stroke.
  • Calcium channel blockers: These prevent calcium from entering the muscle cells of your heart and blood vessels, allowing them to relax.
  • Diuretics: These reduce stress on your heart by removing excess fluid from your body.

Valvuloplasty

Valvuloplasty is a nonsurgical procedure that opens a narrowed mitral valve. It is also known as percutaneous mitral balloon commissurotomy or percutaneous mitral balloon valvotomy. Your doctor might recommend this as a less invasive alternative to surgery if your mitral valve is only slightly damaged.

Your doctor will insert a catheter into your vein and use it to move a small balloon through your bloodstream to your heart and mitral valve. Under the guidance of X-rays, the balloon is inflated to open the valve.

Surgery

If you have moderate to severe mitral stenosis, your doctor may recommend surgery to address the narrowing or to repair or replace a severely damaged mitral valve. Surgical options include:

  • Commissurotomy: Commissurotomy separates the flaps or leaflets of your mitral valve, opening it to improve blood flow. If balloon commissurotomy is not suitable for you, this procedure may be performed as open surgery.
  • Valve repair: Your surgeon may try to repair a faulty valve instead of replacing it. They may trim, shape, or rebuild your valve flaps to allow blood to flow better.
  • Valve replacement: Your surgeon may replace a faulty valve with a mechanical one or a biological one from animal or human tissue.

Locations for mitral stenosis

Find the experienced, nationally recognized care you need for mitral stenosis and other heart valve diseases at Baylor Scott & White. We can help you find care in North and Central Texas at the location that meets your needs.

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Global Heart Health Center

Global Heart Health Center

4716 Alliance Blvd Pavilion II, Ste 300, Plano, TX, 75093

902.3 mi Directions

Frequently asked questions

  • Is mitral stenosis a diastolic murmur?

    Yes, mitral stenosis causes a diastolic murmur. In mitral stenosis, the mitral valve is narrowed causing a turbulent blood flow which produces a rumbling diastolic murmur.

  • Can mitral stenosis be reversed?

    Mitral stenosis is a lifelong condition. You cannot reverse it through medicine or lifestyle changes. However, you can treat the symptoms and reduce your risk of serious complications. Surgery and other procedures can address structural problems and improve blood flow through your heart.

  • Can mitral stenosis cause heart failure?

    Yes, mitral stenosis can cause congestive heart failure. A narrowed valve can restrict blood flow through your heart, increasing stress on the heart and reducing its ability to pump oxygen-rich blood to the rest of your body.

  • Can mitral stenosis cause sudden death?

    Mitral stenosis increases your risk for developing atrial fibrillation or heart failure, a condition that can cause sudden cardiac death. Mitral stenosis can also increase your chance of a stroke, another condition that can lead to sudden death.

  • How do you repair mitral stenosis?

    Your doctor can repair mitral stenosis with procedures to open, repair or replace the valve. You can’t repair mitral stenosis with medications, but medications can help you manage symptoms.

  • What is the life expectancy of someone with mitral stenosis?

    Life expectancy varies depending on your age and how severe your condition is. Many people live for years with no symptoms. Once symptoms develop, around 20% of people survive for 10 years. Those who develop pulmonary hypertension survive on average three years.

  • What happens if mitral stenosis is left untreated?

    If left untreated, mitral stenosis can lead to severe complications, including infections, stroke and heart failure.

    You may not need medical treatments if you have mild mitral stenosis, but your doctor can monitor you to see if the condition gets worse over time. If it does, treatments can help you control symptoms or address problems with your heart valve.

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