Pulmonary Valve Stenosis

Pulmonary valve stenosis is the term describing a narrowing in the opening of the pulmonary valve. The pulmonary valve functions as a one-way valve that allows blood to move from the right ventricle (pumping chamber) into the artery to the lungs and prevents blood from leaking back into the right ventricle.

Pulmonary valve stenosis is almost always congenital, meaning that the child is born with the narrowing of the valve. It is the second most common congenital heart defect in babies.

The pulmonary valve has three leaflets (flaps) which open as the right ventricle contracts (squeezes) to allow blood to go to the lungs and then closes as the ventricle relaxes to prevent blood from running backward (regurgitation). If this valve does not open normally, the right ventricle must work harder to develop enough pressure to push blood through the narrow opening in the valve.

Over time, the extra work for the right ventricle can result in an increased risk of heart-rhythm problems and in limitations in its ability to pump blood.

Children with mild to moderate pulmonary stenosis may not have any symptoms. Those with more severe severe pulmonary valve stenosis usually have symptoms shortly after birth, which may include:

• Cyanosis (bluish tinge to the skin)
• Lack of energy
• Pale, cool, or clammy skin

In rare cases, older children can have symptoms that include:

• Feeling unable to exercise
• Heavy and rapid breathing
• Fatigue

Pulmonary valve stenosis occurs due to improper development of the pulmonary valve in the first eight weeks of fetal growth. Most of the time, this heart defect occurs by chance, with no clear reason for its development.

The most common signs of pulmonary valve stenosis in a newborn are blueness (cyanosis, lower oxygen levels) and the presence of a heart murmur. The degree of cyanosis is measured with a pulse oximeter device that is now found in all newborn nurseries. If your newborn has any symptoms that suggest a heart problem such as pulmonary valve stenosis, your pediatrician will refer you to a pediatric cardiologist.

The cardiologist will do a complete exam and listen for a heart murmur. The specific location and sound of the murmur will give the cardiologist an initial idea of what kind of heart problem your baby may have.

Your child’s doctor may also order one or more of the following tests to diagnose:

• Electrocardiogram (EKG or ECG)
• Echocardiogram (cardiac ultrasound)

Children with mild pulmonary valve stenosis don’t usually need treatment. However, they do require follow up over time, since in some patients, the degree of obstruction can progress.

Those who have moderate to severe stenosis are most often treated by cardiac catheterization (balloon dilation or valvuloplasty). During this procedure the doctor inserts a small, flexible tube (catheter) with a deflated balloon on the tip. Once the balloon is positioned across the narrowed valve, the balloon is inflated to stretch the valve open. This procedure is performed under sedation or anesthesia to ensure the patient does not feel any discomfort. Most patients are discharged either the same day of the procedure or the following day, after a brief period of observation.

In some cases, pulmonary valve stenosis may be repaired by open-heart surgery, although this is less common. Some infants with severe pulmonary valve stenosis may need emergency care prior to treatment.

Most children will live healthy lives with normal growth, no restrictions on exercise and activities, and no risks associated with pregnancy later in life.

Even so, most people who’ve had congenital-heart-disease repair will have an ongoing relationship with their cardiologist, since they’ll always be at some risk for arrhythmias, infections, and other problems. Your child’s cardiologist will help you create a long-term care program as your baby matures into childhood, the teen years and even adulthood.

A small number of children may have leakage and calcifications (calcium deposits) from the repaired valve later in life. In some cases, they may need further treatment or valve replacement. Valve replacement may be done using open-heart surgery or using a technique in which a valve is inserted through a catheter and then expanded in the location of the pulmonary valve. Both of these procedures are carried out at Boston Children's Hospital.

The Benderson Family Heart Center at Boston Children's Hospital is the largest pediatric heart program in the U.S. Our staff of more than 80 pediatric cardiac specialists care for thousands of children and adults with congenital and acquired heart defects each year, from simple to complex cases. We have experience treating rare heart problems with success rates that are among the best in the world.

Part of our approach to valve repair is finding new ways to get more accurate imaging information with tools such as three-dimensional (3D) modeling, echocardiograms, and cardiac magnetic resonance imaging (MRI). Through use of advanced imaging, our specialists can better understand valve dysfunction and find the appropriate treatment.

The pediatric cardiologists and cardiac surgeons at Boston Children's have pioneered several of the interventional catheterization-repair techniques, now used widely for many congenital heart defects, including pulmonary valve stenosis.

Clinical heart researchers at Boston Children’s have created a Congenital Heart Valve Program with a focus on valve repair, rather than replacement. The program has formed in response to the greater emphasis currently being placed on identifying and treating valve abnormalities in children and young adults with congenital heart disease.