Pulmonary Artery Stenosis

What is pulmonary artery stenosis?

Pulmonary artery stenosis is narrowing in the pulmonary artery, a large blood vessel that connects the right ventricle to the lungs. In the lungs, blood picks up oxygen to carry to the body. Narrowing in the pulmonary artery makes it hard for blood to reach your child’s lungs. Without enough oxygen, your child’s heart and body can’t function as they should.

Narrowing may occur in the main pulmonary artery and/or in its left or right branches. When this occurs, the right ventricle must work harder to pump blood across the narrowing. Over time, this can cause damage to the heart muscle.

Pulmonary artery stenosis complications

Without treatment, this condition can lead to right-sided heart failure.

Who does pulmonary artery stenosis affect?

Pulmonary artery stenosis is relatively rare. It may affect children who were born with other heart issues (congenital heart disease), or it can occur in isolation (without other heart defects). It also may develop after certain heart surgeries.

What are the symptoms?

Symptoms depend on the severity of the stenosis (narrowing). If the narrowing is mild, your child may not have symptoms. As the narrowing becomes severe, your child may experience the following:

• Shortness of breath.
• Fatigue.
• Heavy or rapid breathing.
• Rapid heart rate.
• Swelling in the feet, ankles, face, eyelids and/or abdomen.
• Dizziness or passing out.
• Cyanosis (blue discoloration) of the lips, fingers, and toes.
• Reduced exercise tolerance (not able to keep up with other kids or play as much as usual).

What causes pulmonary artery stenosis?

Some people are born with pulmonary artery stenosis and have problems with their heart valves, walls or other parts of their heart as well. Others who have pulmonary artery stenosis at birth have no other heart issues. You can also develop the condition after heart surgery or from diseases that aren’t very common.

Congenital (since birth) causes of pulmonary artery stenosis

In 40% of cases, people are born with pulmonary artery stenosis but don’t have other heart problems.

Pulmonary artery stenosis happens in 2% to 3% of people who have other congenital (since birth) heart defects, such as:

• Tetralogy of Fallot: A condition characterized by four problems in your child’s heart, impairing normal blood flow.
• Pulmonary atresia: A defect in which the pulmonary valve, which connects the right ventricle to the pulmonary artery, doesn’t form at all. This keeps blood from flowing to your child’s lungs.
• Truncus arteriosus: One combined heart artery instead of the normal two lets oxygen-rich blood blend with oxygen-poor blood.
• Aortic valve stenosis: A problem with this valve reduces how much blood goes from your child’s heart to their body.
• Atrial septal defect: A hole in the wall between your child’s two upper heart chambers (atria) lets blood with and without oxygen mix.
• Ventricular septal defect: A hole in the wall that separates your child’s two lower chambers (ventricles) can make too much blood go to their lungs.
• Transposition of the great vessels: The two major arteries that carry blood away from your child’s heart are in each other’s places. This impairs normal blood flow and limits how much oxygen can get to your child’s cells.
• Patent ductus arteriosus: This is a connection between your child’s pulmonary artery and aorta. If it doesn’t close after birth as it should, too much blood goes to the lungs.

Other causes of pulmonary artery stenosis can include issues such as:

• Rubella syndrome, a group of heart and other health problems your child gets from a rubella infection their birthing parent has while pregnant.
• Williams syndrome, a group of abnormalities affecting your child’s heart and other organs.
• Alagille syndrome, which causes liver problems and heart issues.
• Takayasu’s arteritis, a type of inflammation that damages large blood vessels.
• Problems that compress your child’s pulmonary artery from the outside.

Surgical causes of pulmonary artery stenosis

Some people get pulmonary artery stenosis after having a surgical procedure. These include:

• Lung transplant.
• Surgery to fix your child’s congenital heart issue or improve blood flow through their heart.
• Pulmonary artery banding. This purposely narrows your child’s artery to reduce blood flow to their lungs.

How is pulmonary artery stenosis diagnosed?

Your child’s healthcare provider may hear abnormal heart sounds (a murmur) during an exam. If this happens, they’ll order other tests that can include:

• Electrocardiogram (ECG or EKG): A test that records the electrical changes that occur during a heartbeat, reveals abnormal heart rhythms (arrhythmias) and detects heart muscle stress.
• Chest X-ray: A test to show the size and shape of the heart, lungs and pulmonary arteries.
• Echocardiogram: A test that uses sound waves to make a moving picture of the heart muscle and valves.
• Cardiac magnetic resonance imaging (MRI): A test that uses three-dimensional imaging to show how blood flows through your child’s heart and vessels.
• CT scan: An X-ray procedure that uses a computer to combine many X-ray images of your child’s heart into cross-sectional views. IV contrast (dye) lets your child’s provider see their heart’s anatomy and blood circulation.
• Cardiac catheterization: A procedure that involves inserting a thin tube (catheter) into a vein or artery and passing it into the heart. A provider can check the level of oxygen, measure pressure changes and make X-ray movies of the heart.
• Pulmonary angiography: A dye-enhanced X-ray of your heart’s pulmonary arteries and veins.
• Perfusion scan: A test in which you get an injection of a small amount of a radioactive material. A special machine shows how well blood is flowing through each lung.

If your child’s healthcare provider diagnoses them with pulmonary artery stenosis, they’ll recommend that you meet with a congenital heart specialist. This type of provider has the training and equipment to determine your child’s heart problem and order the necessary special tests, medical care, heart surgery and follow-up checkups. They may order additional tests as necessary.

Your child’s provider may talk about their condition in terms of a Type I, II, III or IV. These are categories based on how many parts of the artery are narrow and where these spots are located.

How do you fix pulmonary artery stenosis?

The best treatment approach will depend on your child’s symptoms and other factors. Mild to moderate narrowing in one or more pulmonary artery branches usually doesn’t require treatment. However, severe cases need treatment.

Pulmonary artery stenosis treatments include:

Balloon dilation (angioplasty)

Your child’s provider will:

1. Move a balloon dilation catheter into the narrowed area of the artery.
2. Carefully inflate the balloon, going from low pressure to higher pressure.
3. Widen the narrowed artery.
4. Deflate and remove the balloon.

Balloon dilation and stent placement (preferred method)

Your child’s provider will:

1. Position a balloon-expandable stent across the artery’s narrow part.
2. Mount the stent on a balloon angioplasty catheter and cover it with a sheath.
3. Move the stent into position.
4. Remove the sheath from the stent-balloon angioplasty assembly.
5. Inflate the balloon to the right pressure, expand the stent and anchor it in place.

The Cutting Balloon™

This balloon is similar to a standard one. However, the balloon has small blades running up and down its length. When your child’s surgeon inflates the balloon, they activate the blades, which cut through the narrowed area. This makes the vessel easier to dilate and results in a larger opening.

This option gives good results for many people who don’t have an associated congenital heart problem. However, the artery can become narrow again in as many as 21% of people over several months.

Surgery

Surgeons use various methods to repair pulmonary artery stenosis. The choice depends on what the stenosis is like. They also look at the surrounding vessels and other structures.

Complications of the treatment

Balloon dilation improves narrowing in a majority of people. However, over time, the artery can become narrow again in as many as 15% to 20% of cases. This means your child’s provider will need to do the procedure again. Researchers are working on different types of balloons that will likely lead to better and longer-lasting results.

Balloon dilation complications include:

• Pulmonary artery aneurysm.
• Pulmonary artery dissection.
• Pulmonary artery rupture.
• Pulmonary edema (swelling).

It can also be fatal.

Complications of stent use include:

• Blood clots.
• Ventricular arrhythmias.
• Stents being put in the wrong place or moving out of place.
• Need for expanding an artery again (rare).

Benefits of treatment

Healthcare providers prefer stents because they:

• Are up to 96% effective right away.
• Are effective long-term in keeping an artery open.
• Can double the size of the narrow part.
• Are more cost-effective than balloon dilation or surgery.
• Are more effective than balloon angioplasty.

Providers may choose balloon angioplasty instead of a stent when:

• Your child’s condition is severe.
• Your child’s anatomy is complex.
• Your child is very small.

What happens after surgery?

If your child receives a stent, they’ll take antibiotics and possibly blood thinners for a while. These medicines prevent infections and blood clots.

How soon after treatment will my child feel better?

Procedures to expand your child’s pulmonary artery work right away. This means your child will have an easier time getting blood to their lungs to get oxygen.

What can I expect if my child has pulmonary artery stenosis?

With today’s advances in medical treatment, many people with this condition live to be adults. However, people with conditions like Williams syndrome and Alagille syndrome don’t respond as well to treatments.

When should my child see their healthcare provider?

Your child will need regular checkups with their provider to see how they’re doing. Also, they’ll need regular echocardiograms to see if their artery needs to be expanded again in the future.

What questions should I ask my doctor?

• What caused pulmonary artery stenosis in my child?
• Which treatment is best for my child?
• What are the chances that my child will need treatment again for this?

A note from Cleveland Clinic

If your child needs treatment for pulmonary artery stenosis, their healthcare provider will consider the best treatment for your child’s situation. You should feel comfortable asking questions about anything you don’t understand about your child’s procedure.