Tricuspid Atresia

What is tricuspid atresia?

Tricuspid atresia is a congenital heart defect, occurring in two out of every 10,000 live births. Relatively rare, it accounts for about 1 to 2 percent of all cases of congenital heart disease.

In tricuspid atresia, the tricuspid valve — which is normally located between the right atrium and the right ventricle — is missing, as is the right ventricle. While very serious, tricuspid atresia is treatable surgically, and surgical advances have greatly improved outcomes.

In a normal heart, oxygen-poor (blue) blood returns to the right atrium from the body, travels to the right ventricle, then is pumped through the pulmonary artery into the lungs, where it receives oxygen. And oxygen-rich (red) blood returns to the left atrium from the lungs, passes into the left ventricle, then is pumped through the aorta out to the body.

In tricuspid atresia, lack of development of the tricuspid valve prevents oxygen-poor (blue) blood from passing from the right atrium to the right ventricle and on to the lungs as it should. Instead, blood passes from the right atrium to the left atrium and then to the only pumping chamber, the left ventricle. In most children with tricuspid atresia, the artery to the lungs is connected to the left ventricle by a ventricular septal defect. 

tricuspid atresia illustration

Additional defects

Like many congenital heart conditions, tricuspid atresia isn’t a single defect, but rather a cluster of associated defects in various combinations and with varying degrees of severity.

Essentially all children with atrial septal defect (ASD) and most have ventricular septal defect (VSD). These defects are holes in the tissue walls that normally separate the right and left atria (ASD) and the right and left ventricles (VSD).

These ASDs and VSDs are actually useful in this condition, since they allow oxygen-poor (blue) blood and oxygen-rich (red) blood to mix, providing some oxygen to circulate. The ASD allows blood returning from the body to enter the single pumping chamber (the left ventricle), where the blood is pumped to the lungs and to the body. The VSD allows blood to be pumped to the the lungs from the left ventricle. But the heart often has to work extra hard with this set-up, which is not as efficient as having two pumping chambers.

Some children may also have a defect called patent ductus arteriosus. In this condition, a blood vessel (ductus arteriosus), which connects the two great arteries (aorta and pulmonary artery), and which usually closes soon after birth, fails to do so. The ductus arteriosus remains open (patent), allowing blood to pass from the aorta to the pulmonary artery. This is helpful if the VSD is very small or there is narrowing of the pulmonary valve, since it allows enough blood to get to the lungs for enough oxygen. But the ductus is subject to closing without warning, and children who need a patent ductus arteriosus for adequate blood flow to the lungs, require it to be replaced by a shunt.

Some children also have transposition of the great arteries (TGA), in which the normal positions of the aorta and pulmonary artery are reversed. These children often also have narrowing of the major blood vessel going to the body (the aorta).

How we care for tricuspid atresia

The Boston Children’s Hospital Cardiac Surgery Department treats some of the most complex pediatric heart conditions in the world, such as tricuspid atresia, with survival rates exceeding 98 percent.

We provide families with a wealth of information, resources, programs and support — before, during and after your child’s treatment. With our compassionate, family-centered approach to expert treatment and care, your family and your child are in the best possible hands.

The Adult Congenital Heart and Pulmonary Hypertension Program (BACH) provides long-term inpatient and outpatient care and advanced therapeutic options for patients with congenital heart disease and pulmonary hypertension as they move through adulthood.