What is mitral valve stenosis?

Mitral valve stenosis, also known as mitral stenosis, occurs when the mitral valve opening is narrowed and only a small amount of blood can flow through it. The mitral valve is the valve located between the atrium (upper chamber) and ventricle (lower chamber) on the left side of the heart.

An improperly functioning mitral valve can lead to other heart conditions or symptoms including heart failure, blood clots, fatigue or difficulty breathing.

Common related conditions
Aortic Valve Regurgitation Pulmonary Valve Regurgitation Tricuspid Valve Regurgitation

Causes of mitral valve stenosis

Mitral valve stenosis is most commonly caused by rheumatic fever when the disease cause the mitral valve flaps fuse or thicken.

Rheumatic fever is a rare but life-threatening condition that is caused by untreated strep throat. Many patients who develop mitral valve stenosis from rheumatic fever may not know that they ever had rheumatic fever.

Other causes of mitral valve stenosis include:

  • Congenital heart defect — being born with a narrow mitral valve at birth
  • Calcium deposits on the mitral valve
  • Chest radiation
  • An autoimmune disease, such as lupus

Risk factors for mitral valve stenosis

Risk factors for mitral valve stenosis include:

  • History of rheumatic fever — patients who have had rheumatic fever are at higher risk for mitral valve stenosis.
  • Age — older people are at higher risk of developing mitral valve stenosis.
  • Gender — women are more likely to develop mitral valve stenosis than men.

Symptoms of mitral valve stenosis

Mitral valve stenosis can progress slowly over years or even decades before more serious symptoms develop.

If you have any of the following symptoms, contact your doctor right away:

  • Shortness of breath even during rest
  • Feeling weak or fatigued
  • Swollen legs or feet
  • Heart palpitations
  • Dizziness or fainting
  • Chest pain or discomfort
  • Coughing up blood

Diagnosis of mitral valve stenosis

You can live years with mitral valve stenosis before experiencing symptoms. For patients with symptoms, mitral valve stenosis can be diagnosed in a physical exam.

In the physical exam, your doctor will check for a heart murmur, listen for lung congestion and order diagnostic tests.

Diagnostic tests that confirm the diagnosis and determine the severity include:

  • Chest x-ray — takes pictures of your heart and lungs to determine if there are abnormalities.
  • Echocardiogram — can take detailed images of the mitral valve to determine if there is damage.
  • Electrocardiogram (ECG or EKG) — provides information about your heart’s rhythm.

Treatment for mitral valve stenosis


Medications can be used to treat mitral valve stenosis in patients who are experiencing symptoms, they include:

  • Anticoagulants — blood thinners
  • Diuretics — reduce fluid buildup
  • Antiarrhythmics — treat abnormal heart rhythms
  • Beta-blockers — slow down the heart rate


The goal of treatment for mitral valve stenosis is to repair or replace the mitral valve. Your doctor will evaluate the severity of the stenosis, shape of mitral valve and symptoms you are having to determine what treatment is appropriate for you.

If symptoms are severe, the cardiologist may recommend one of the following procedures:

  • Percutaneous balloon mitral valvuloplasty (balloon valvotomy) — a catheter with a deflated balloon on the end is inserted into the narrowed valve, once in the correct location, the balloon will be inflated to open the valve.
  • Mitral valve repair surgery (commissurotomy) — scar tissue and calcium deposits on the valve are removed to widen the opening of the valve.
  • Mitral valve replacement surgery — the damaged valve is replaced with a mechanical or biological tissue valve made from cow, pig or human heart tissue.

When possible, your Mercy Health doctor will perform the mitral valve repair or replacement using minimally invasive surgery.

During a minimally invasive mitral valve surgical repair or replacement, the doctor will make a smaller incision on the right side of the chest — two to four centimeters, as compared to six to eight centimeters in the middle of the chest with a traditional open-heart surgery. The procedure requires the use of a heart-lung machine that allows the heart to be stopped during the valve repair or replacement process.

Patients who have mitral valve stenosis only (no other valve disorders) may be candidates for minimally invasive surgery.

Benefits of minimally invasive mitral valve repair or replacement surgery include:

  • Faster recovery
  • Minimal scarring
  • Less trauma to nerves, tissues and muscles

Find a cardiologist nearby

Mercy Health locations that can treat you