Heart and Blood Conditions

Tetralogy of Fallot

What is tetralogy of Fallot?

Tetralogy of Fallot (pronounced teh-TRAHL-ah-jee of fah-LOH) is a rare, congenital condition that changes the normal flow of blood through the heart.

Tetralogy of Fallot involves 4 birth defects in the heart’s structure:

  1. The first is a large hole in the septum, or wall, between the right and left ventricles. This hole is called a ventricular septal defect. It allows oxygen-poor blood to mix with oxygen-rich blood in the ventricles.
  2. The second is a narrowing (stenosis) of the pulmonary valve. This limits blood flow from the right ventricle to the lungs. It forces some oxygen-poor blood through the ventricular septal defect into the aorta, the artery that carries blood from the heart to the body.
  3. The third problem is a thickening of the muscle wall in the right ventricle (right ventricular hypertrophy). It happens because the right ventricle has to work harder to try to get blood through the pulmonary valve.
  4. The fourth problem is when the aorta leaves the heart from a different spot, right over the ventricular septal defect. This is called overriding aorta. Normally, the aorta leaves the heart from the left ventricle.

Together, the 4 defects limit flow of oxygen-poor blood from the heart to the lungs, where it should pick up oxygen. Instead, oxygen-poor blood leaves the heart and goes out to the rest of the child’s body.

Tetralogy of Fallot at Seattle Children’s

Our heart team has treated many children with tetralogy of Fallot. We have years of experience with the surgery these patients require. We also have a pediatric cardiac anesthesia team and a cardiac intensive care unit ready to care for children who go through 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), cardiac surgeons, cardiac anesthesiologists, cardiac intensive care specialists, newborn specialists (neonatologists), lung doctors (pulmonologists), advanced nurse practitioners, nurses, child life specialists, social workers and others will care for your child, if their help 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 their fields and in meeting the unique needs of children. For example, the doctors who give your child sedation (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.

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

Tetralogy of Fallot in Children

In recent years, the diagnosis and treatment of tetralogy of Fallot has improved greatly. Now, most children with this heart defect grow to adulthood and lead active lives.

Tetralogy of Fallot occurs in about 5 in every 10,000 babies. Children with this problem may have other disorders that they are born with (congenital defects), including genetic disorders such as Down syndrome and DiGeorge syndrome.

Contact Us

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