Mitral Stenosis – Causes, Symptoms, Diagnosis, & Treatment
What is mitral stenosis?
Mitral stenosis (MS) refers to narrowing of the mitral valve opening. This condition occurs when the mitral valve doesn’t open properly due to some structural problem. The valve between the 2 chambers of the left side of your heart is called the mitral valve. Blood flows from the left upper chamber of the heart (left atrium) to the left lower chamber (left ventricle) through the mitral valve. Mitral stenosis restricts the flow of blood resulting in less blood flow to the body.
What causes mitral stenosis?
The most common cause of mitral stenosis is rheumatic fever. Rheumatic fever develops after an illness with strep throat that was not properly treated. MS may occur 5 to 10 years or more after having rheumatic fever.
Mitral stenosis in children is mostly congenital. Mitral stenosis or other birth defects involving the heart that cause mitral stenosis may be present at birth. In many cases, other heart defects are present along with the mitral stenosis.
Mitral stenosis may also run in families.
Rarely, the following factors may also cause mitral stenosis:
- Formation of calcium deposits around the mitral valve
- Radiation treatment to the chest
- Certain medications
What are the symptoms of mitral stenosis?
Mitral stenosis may occur 5 to 10 years or more after having rheumatic fever. Sometimes, symptoms may not appear even after much longer time. However, symptoms can appear or get worse with exercise or other activity that raises the heart rate. Symptoms mostly develop between ages 20 and 50.
Symptoms may start with an episode of atrial fibrillation. Symptoms can be triggered by pregnancy or other stress on the body, such as infection in the heart or lungs, or other heart disorders.
The following are the symptoms that may occur:
- Trouble breathing during or after exercise
- A cough (sometimes with bloody phlegm)
- Palpitations (pounding heartbeat)
- Edema of feet or ankles
- Waking up due to breathing problems
- Frequent bronchitis or other respiratory infections
- Chest discomfort that increases with activity and extends to the arm, neck, jaw or other areas (this occurs rarely)
Symptoms can be present from birth in children. MS mostly develops within the first 2 years of life. The following symptoms may appear in children:
- Shortness of breath
- A cough
- Poor feeding, or sweating when feeding
- Poor growth
How is mitral stenosis diagnosed?
The doctor will perform a physical exam and review the symptoms and medical history. The doctor will listen to the heart and lungs with a stethoscope. He/she looks for any abnormal heart sounds, such as murmur, snap, or irregular heartbeat. The exam may also reveal lung congestion.
The doctor may order some of the following tests to find out narrowing or blockage of the valve or swelling of the upper heart chambers:
- MRI of the heart
- CT scan of the heart
- Chest x-ray
- ECG (electrocardiogram)
- Transesophageal echocardiogram (TEE)
How is mitral stenosis treated?
Treatment of MS varies depending on the symptoms and condition of the heart and lungs. Treatment is not required for people with no symptoms or mild symptoms. People with severe symptoms may be admitted to the hospital for treatment.
Treatment With Medicines
The doctor may prescribe medicines if the mitral stenosis is causing symptoms. These medicines may alleviate the symptoms, but cannot fix or repair the mitral stenosis. They may address other heart problems, which contribute to mitral stenosis.
The doctor may prescribe the following medicines:
- Anticoagulants (blood thinners) to decrease blood clot risk
- Diuretics (water pills) to decrease fluid buildup
- Antiarrhythmic medicines, such as nitrates, beta-blockers, calcium channel blockers to suppress abnormal rhythms of the heart
- ACE inhibitors to regulate blood pressure
- Angiotensin receptor blockers (ARBs) to treat blood pressure and heart failure
- Digoxin to treat various heart conditions
Doctors also use valvuloplasty, also called percutaneous mitral balloon valvotomy, to repair the mitral valve. During this procedure, the doctor attaches a balloon to a catheter and threads it into your heart through a vein, usually in the leg. Once it reaches mitral valve, the doctor inflates the balloon to expand the valve.
If the medical treatment and valvuloplasty don’t work, some people may need surgery to repair or replace the mitral valve.
This feature is for informational purposes only and is not intended to substitute the expert guidance of a doctor. We advise seeing a doctor if you have any health concerns.