Pulmonary Stenosis

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What is pulmonary stenosis?

Pulmonary stenosis (PULL-muh-neh-ree steh-NO-sis) is when the pulmonary valve cannot open fully. The pulmonary valve is the one-way door that lets blood flow from the right lower chamber (ventricle) of the heart to the lungs, where the blood gets oxygen.

Because the pulmonary valve cannot open all the way, the right ventricle must pump harder to move blood to the lungs. As a result, the right side of the heart may get larger and thicker.

How serious is pulmonary stenosis?

Pulmonary stenosis may be the only heart problem your child has, or it may be part of a more complex heart condition.

The effects can vary widely. A newborn or young infant with severe pulmonary stenosis can be very sick. But most children with the condition have a mild form, are healthy and have no symptoms at all. They may never have any health problems from their pulmonary valve.

Some forms of pulmonary stenosis can become worse with time. Most children with this condition see a cardiologist for many years to check their health and treat any problems.
What causes pulmonary stenosis?

Sometimes, babies are born with pulmonary stenosis. We do not know why the pulmonary valve forms abnormally in some babies. Genetics may play a role. For example, pulmonary stenosis often occurs in children with Noonan syndrome.

Pulmonary stenosis can also start later in life as a result of some other condition that damages the heart valves, such as rheumatic fever.

Heart Center at Seattle Children's

Our pediatric cardiologists and cardiac surgeons have more advanced training and experience operating and performing procedures on babies, children and teens than at any other children's hospital in the Pacific Northwest.

Symptoms of Pulmonary Stenosis

Some children with pulmonary stenosis do not have any symptoms. They may have no health problems that they or their families would notice unless the condition gets worse.

If your child does have symptoms, these may get worse with exercise or activity.

Babies may have symptoms like these:

Working hard to breathe
Poor appetite
Trouble feeding
Poor weight gain or slow growth (failure to thrive)
Cyanosis

Newborns with these symptoms need treatment right away.

Children past infancy may have these symptoms:

Working hard to breathe
Poor appetite
Cyanosis
Feeling short of breath when active
Having pain, pressure or tightness in their chest
Fainting or feeling weak or dizzy when active
Being more tired than normal

Diagnosing Pulmonary Stenosis

Fetal diagnosis

Sometimes doctors can diagnose pulmonary stenosis in a developing baby before they are born. They might first see something different about your baby’s heart on standard prenatal ultrasound. To learn more, you might have an ultrasound done to check the heart more closely (fetal echocardiogram).

Our Fetal Care and Treatment Center team can care for you when you are pregnant if your developing baby has a known or suspected problem.
Diagnosis after birth
To diagnose this condition, your child’s doctor will examine your child, use a stethoscope to listen to their heart and check their blood pressure. Sometimes, doctors find pulmonary stenosis after hearing a heart murmur in a child who appears well.

The doctor will ask for details about any symptoms your child has, their health history and your family health history.

Your child will need an echocardiogram test so the doctor can see how their heart works.

They may need other tests that provide more information about their heart. These may include:
- Chest X-rays
- MRI (magnetic resonance imaging) of the heart
- Cardiac catheterization
- Electrocardiogram (ECG or EKG)

Treating Pulmonary Stenosis

Not all children with pulmonary stenosis need treatment. If the stenosis is mild, your child may not need any kind of treatment. But all children with this condition need lifelong care to check their condition in case it starts to get worse.

Some children with pulmonary stenosis need treatment right away because their heart cannot pump enough blood and oxygen to the rest of their body.

We may use a balloon procedure (valvuloplasty) to treat your child in the catheterization lab. Our doctors insert a balloon across the valve. When they inflate the balloon, it stretches the valve open. Then, they remove the balloon.

If the stenosis is severe enough, some children need surgery to open the valve and increase blood flow to the lungs.

Pulmonary Stenosis at Seattle Children’s

The experts you need are here
- The Heart Center team includes more than 40 pediatric cardiologists who diagnose and treat every kind of heart problem. We have diagnosed many children with pulmonary stenosis.
- Not all children with this condition need treatment. We check your child carefully to make sure they get any treatment they do need — and they are not put through procedures they do not need.
- Our doctors and surgeons are experts in the treatments for pulmonary stenosis. These include cardiac catheterization or surgery to open or replace the pulmonary valve.
- We also have a pediatric cardiac anesthesia team and a Cardiac Intensive Care Unit ready to care for children who have heart surgery.
- Your child’s team includes other experts from Seattle Children’s based on their needs, like neonatologists or pulmonologists.
Care from before birth through young adulthood
- If your developing baby is diagnosed with pulmonary stenosis before birth, our Fetal Care and Treatment Center team works closely with you and your family to plan and prepare for any care your baby may need.
- Your child’s treatment plan is custom-made. We plan and carry out their treatment based on the specific details of their illness.
- All children with this condition need lifelong visits with a cardiologist in case their condition worsens. We closely check your child’s needs to make sure they get the care that is right for them at every age.
- We have a special Adult Congenital Heart Disease Program to meet your child’s long-term healthcare needs. This program, shared with the University of Washington, transitions your child to adult care when they are ready.
Support for your whole family
- We are committed to your child’s overall health and well-being and to helping your child live a full and active life.
- Whatever types of care your child needs, we will help your family through this experience. We will discuss your child’s condition and treatment options in ways you understand and involve you in every decision.
- Our Child Life specialists know how to help children understand their illnesses and treatments in ways that make sense for their age.
- Seattle Children’s has many resources, from financial to spiritual, to support your child and your family and make the journey as smooth as possible.
- Many children and families travel to Seattle Children’s for heart surgery or other care. We help you coordinate travel and housing so you can stay focused on your child.
- Read more about the supportive care we offer.