Mitral Stenosis—Child

Definition

Mitral stenosis is a narrowing of the mitral valve in the heart. This valve is in the left side of the heart between two chambers called the atrium and the ventricle. Blood must flow from the atrium, through the mitral valve, and into the ventricle before being pumped out into the rest of the body. Mitral stenosis causes poor blood flow between the two left chambers. As a result, too little blood and oxygen is pumped throughout the body.

Mitral Valve Stenosis

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Causes

The most common cause of mitral stenosis is rheumatic fever. This scars the mitral valve. A less common cause is a birth defect. Very rare causes include:

• Blood clots
• Tumors
• Other growths that block blood flow through the mitral valve

Risk Factors

The main risk factor is rheumatic fever. Other risk factors may include:

• Being born with mitral valve problems
• Having other health problems that affect blood flow in the heart

Symptoms

Symptoms may include:

• Hard time breathing, especially during exercise and when lying flat
• Waking up short of breath in the middle of the night
• Tiredness
• Chest pain, like squeezing, pressure, or tightness (rare)
• Sensation of rapid or irregular heartbeat
• Cough with exertion
• Coughing up blood
• Swelling of the legs or feet
• Frequent respiratory infections
• Dizziness, fainting

Diagnosis

The doctor will ask about your child’s symptoms and medical history and do a physical exam. The doctor may discover mitral stenosis from:

• Abnormal chest sounds, such as a heart murmur or snap
• Stretching of a vein in the neck
• Signs of fluid in the lungs

Tests may include:

• Chest x-ray —a test that uses radiation to take pictures of structures inside the chest
• Electrocardiogram (ECG, EKG)—a test that records the heart's activity by measuring electrical currents through the heart muscle
• Echocardiogram —a test that uses sound waves to examine the size, shape, and motion of the heart (In this test, the sound waves are passed through a transducer that is placed onto your child’s chest.)
• Transesophageal echocardiogram —uses the same sound wave techniques to create an image of your child’s heart (In this test, the transducer is passed down your child’s esophagus. This is the tube that runs from the mouth into the stomach. This allows the doctor to better examine the mitral valve.)
• Cardiac catheterization —an x-ray of the heart's circulation that is done after injection of a contrast material
• Stress test —tests how the body responds to exercise, which can help in detecting heart and lung problems

Treatment

Antibiotics may be needed for certain infections or procedures that may increase the risk for heart infections. If your child has mild mitral stenosis, it will need to be monitored. He may not need immediate treatment for symptoms. If symptoms are treated, your child’s doctor may give certain medicines to improve heart function.

Your child may need surgery to prevent heart damage. Common types of heart valve surgery include:

• Mitral valvulotomy—A surgical cut is made in the stenotic mitral valve to relieve the blockage.
• Balloon valvuloplasty —A balloon device is inserted into the blocked mitral valve. This will open up the valve. This may provide temporary relief of symptoms. But the valve may become blocked again.

Follow the doctor's instructions if your child is diagnosed with mitral stenosis.

Prevention

Most cases of mitral stenosis can be prevented by preventing rheumatic fever. Treat strep throat infections right away to avoid rheumatic fever, which can cause scarring of the heart valve. Always make sure your child finishes all of the antibiotics given, even if he feels better.

There are several other things your child can do to try to avoid some of the complications of mitral stenosis:

• Get regular medical care, including checkups and periodic electrocardiograms.
• Take antibiotics before any dental cleaning, dental work, or other invasive procedures if it is recommended by your doctor. Not all patients with mitral stenosis need antibiotics for these procedures.
• Eat a healthy diet that is low in salt. Work with the doctor or dietician to plan a healthy diet for your child. This may help decrease the pressure in your child’s heart and improve symptoms.
• Monitor blood pressure. Inform the doctor if you notice that your child seems to be developing high blood pressure.