Heart and Blood Conditions

Pulmonary Hypertension

What Is Pulmonary Hypertension?

Pulmonary hypertension (pronounced PULL-mun-airy hi-per-TEN-shun) is high blood pressure in the lungs. It happens when blood vessels in the lungs cannot expand well enough to receive blood coming from the heart.

Normally, the right  ventricle  of the heart pumps oxygen-poor (blue) blood to the lungs to pick up more oxygen. The blood leaves the heart through the  pulmonary artery . The artery branches to become smaller and smaller blood vessels in the lungs. The smallest are the capillaries.

The capillaries have thin walls and run near the small air chambers of the lungs. In the capillaries, the blood absorbs oxygen. Then the oxygen-rich (red) blood flows into larger vessels to return to the heart. It flows into the heart's left side, where the left ventricle pumps it to the rest of the body.

The pulmonary arteries and the smaller blood vessels in the lungs have muscle in their walls. Normally this muscle relaxes or squeezes to allow in more blood or less blood based on the body's needs.

In children with pulmonary hypertension, this muscle is thickened. So their blood vessels cannot expand easily. When their right ventricle pumps blood toward their lungs, the vessel walls resist more than normal.

Pulmonary Hypertension in Children

The main effect of pulmonary hypertension is that it causes the right ventricle to pump harder to get blood to the lungs. Because the right ventricle is working harder, it gets bigger and thicker, and it could fail .

Pulmonary hypertension can have many causes or associated diseases.

In children, one of the most common causes is  congenital  heart disease. Some heart defects can cause pulmonary hypertension because they direct more blood than normal to the pulmonary artery. This is one reason it can be important to repair heart defects, when possible, before the heart or blood vessels are damaged permanently. Often, but not always, pulmonary hypertension will improve after the congenital heart defect is repaired.

Another common cause of pulmonary hypertension in children is lung disease. Lung disease may occur because a baby was born early (prematurely) or they have a congenital lung problem. Children can also get lung disease after being on a mechanical ventilator for a long time. Sometimes, children with obstructive sleep apnea can develop pulmonary hypertension.

Rarely, the cause of pulmonary hypertension is not known, and then we call it idiopathic. In some cases, there is a family history of the condition.

Pulmonary Hypertension at Seattle Children's

Our heart team has treated many children with pulmonary hypertension. We have a  special team and clinic to care just for children with pulmonary hypertension. We have extensive experience with the treatment these patients may require, including oxygen therapy, medicine or surgery to correct an underlying heart defect. We also have a pediatric cardiac anesthesia team and a cardiac intensive care unit  ready to care for children who undergo heart surgery.

When you come to Children's, a team of people will take care of your child. Along with your child's cardiologist, you are connected with sleep specialists, nutritionists, neonatologists, pulmonologists (lung doctors), nurses, child life specialists, social workers and others, if their expertise is needed. We work together to meet all of your child's health needs and help your family through this experience.

Since 1907, Children's has been treating children only. Our team members are trained in their fields and also in meeting the unique needs of children. For example, the doctors who give your child anesthesia are board certified in pediatric anesthesiology. This means they have extra years of training in how to take care of kids. Our child life specialists know how to help children understand their illnesses and treatments in ways that make sense for their age. Our expertise in pediatrics truly makes a difference for our patients and families.

The Adult Congenital Heart Disease Program shared by Children's and the University of Washington can help with care throughout your child's life.