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 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 oxygen. The blood leaves the heart through the pulmonary artery. The pulmonary artery branches out and becomes smaller blood vessels in the lungs. The smallest blood vessels in the lungs are called the capillaries.

The capillaries have thin walls and run near the small air chambers of the lungs. The blood absorbs oxygen in the capillaries. The oxygen-rich (red) blood then flows into larger vessels to return to the heart. The oxygen-rich (red) blood 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 (capillaries) have muscle in their walls. Normally, this muscle relaxes to allow in more blood or squeezes to allow in less blood based on the body’s needs.

In children with pulmonary hypertension, this muscle is thickened. Their blood vessels cannot expand as 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 work harder to pump 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 machine to help them breathe (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 years of experience with the treatment these patients may need, including oxygen therapy, medicine or surgery to correct an existing heart defect. We also have a pediatric cardiac anesthesia team and a Cardiac Intensive Care Unit ready to care for children who have heart surgery.

When you come to Seattle Children’s, a team of people will take care of your child. Along with your child’s heart doctor (cardiologist), you are connected with sleep specialists, nutritionists, newborn specialists (neonatologists), lung doctors (pulmonologists), 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.

Seattle Children’s has been treating children since 1907. Our team members are trained in treating pulmonary hypertension and in meeting the unique needs of children. For example, the doctors who give your child anesthesia (sedation) 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.

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

Contact Us

Contact the Heart Center at 206-987-2015 for a cardiac referral, a second opinion or more information.