[Skip to Content]

Mitral Stenosis


Mitral stenosis is a narrowing of the mitral valve in the heart. This is a valve on the left side of the heart that connects the top chamber called the atrium to the bottom chamber called the ventricle. Blood flows from the atrium through the mitral valve into the ventricle before being pumped out into the rest of the body.

Mitral stenosis can result in poor blood flow between these two left chambers. This can reduce how much blood and oxygen is getting to the rest of the body.

Mitral Valve Stenosis
Nucleus factsheet image
Copyright © Nucleus Medical Media, Inc.


The most common cause of mitral stenosis is rheumatic fever, because it can scar the mitral valve. Some congenital heart defects may also affect the mitral valve and how well it works.

Less common causes of this problem include:

Risk Factors

Mitral stenosis is more common in women. It often appears in adults between of 30 and 50 years of age. Other things that may raise the risk of mitral stenosis are:


Mitral stenosis may cause:

  • Trouble breathing, especially while working out and when lying flat
  • Waking up short of breath in the middle of sleeping
  • Tiredness
  • Fast or irregular heartbeat
  • Cough when doing something that takes effort
  • Coughing up blood
  • Swelling of the legs or feet
  • Lightheadedness and fainting
  • Chest pain, such as squeezing, pressure, or tightness (rare)


The doctor will ask about symptoms and past health. A physical exam will be done. It will focus on the chest and heart.

Pictures will be taken of the heart and chest. This can be done with:

The heart's electrical activity may be tested. This can be done with:

  • ECG
  • Holter monitor—This is worn on the body to measure heart activity over 1 or 2 days


The goals of treatment are to manage symptoms and make sure the heart rate stays in a healthy range. People with mild mitral stenosis may only need monitoring. If symptoms get worse the doctor may advise avoiding intense activity and foods that have a lot of salt.

Treatment options are:

Supportive Care

Some steps that may be advised to manage mitral stenosis include:

  • Limiting salt intake
  • Limiting caffeine and alcohol
  • Physical activity


Medicines can help manage symptoms. The doctor may advise:

  • Medicines that lower the heart rate and help the heart work better
  • Diuretics to prevent fluid buildup
  • Blood thinners
  • Drugs to control heart rhythm

Antibiotics may need to be taken for certain infections. This will help prevent more harm to the heart. They may also be needed before medical and dental procedures.


Common types of heart valve surgery are:

  • Mitral valvulotomy—The stenotic mitral valve is cut to ease the obstruction.
  • Balloon valvuloplasty—A balloon device is put into the blocked mitral valve to open it or make it bigger.
  • Mitral valve replacement—This is for people with severe symptoms or when other treatments have not helped.


To lower the risk of mitral stenosis:

  • Get treated right away for any possible infections, especially strep throat.
  • Manage chronic health problems.


  • Antibiotic prophylaxis for heart patients. Mouth Healthy—American Dental Association website. Available at: https://www.mouthhealthy.org/all-topics-a-z/antibiotic-prophylaxis-for-heart-patients.
  • Infective endocarditis. EBSCO DynaMed website. Available at: http://www.dynamed.com/condition/infective-endocarditis.
  • Mitral stenosis. EBSCO DynaMed website. Available at: http://www.dynamed.com/condition/mitral-stenosis.