Tricuspid atresia is a congenital heart defect manifested by the absence of the tricuspid valve, which is normally located between the right atrium and the right ventricle. This results in underdevelopment of the right ventricle, which cannot adequately pump oxygen-poor blood to the lungs. Without this ventricle, the blood flow cannot take its normal path from the body into the heart, to the lungs, then back to the heart and through the body. The oxygen-poor ("blue") blood crosses a hole between the upper chambers of the heart and mixes with oxygen-rich blood, resulting in low oxygen levels in the child.
The child's survival depends on there being an opening in the wall between the atria (atrial septal defect) and usually an opening in the wall between the two ventricles (ventricular septal defect).
Additional secondary defects found in tricuspid atresia include:
- Atrial septal defects
- Ventricular septal defects
- Pulmonary stenosis and
- Transposition of the great arteries
The presentation and treatment strategies are dependent on the associated defects. Most patients with tricuspid atresia require a staged surgical palliation called a Fontan operation.
The cause of tricuspid atresia is unknown.
- Low oxygen levels
- Cyanosis (bluish skin tone)
Children with tricuspid atresia are at increased risk for developing endocarditis. As a preventive measure, they may need to take antibiotics before certain dental procedures. A pediatric cardiologist can determine whether this is necessary.
- Exercise stress testing
- Advanced imaging with cardiac MRI
- Occasionally, cardiac catheterization
In cases of tricuspid atresia, staged palliation is performed: first, a bidirectional Glenn operation, then a Fontan operation. Other surgical treatments include a shunt and pulmonary artery banding. Lifelong surveillance by a cardiologist is required for assessment of the Fontan circuit and evaluation of the heart’s function.