Tricuspid atresia

[Jessica]

Tricuspid atresia is absence of the tricuspid valve accompanied by a hypoplastic right ventricle. Associated anomalies are common and include atrial septal defect, ventricular septal defect, patent ductus arteriosus, pulmonic valve stenosis, and transposition of the great arteries. Presenting signs include cyanosis or signs of heart failure. The first heart sound (S1)is single and may be accentuated. The 2nd heart sound (S2) is usually single. Most infants have a murmur, the nature of which depends on the presence of associated anomalies. Diagnosis is by echocardiography. Cardiac catheterization may be needed. Definitive treatment is surgical repair.
(See also Overview of Congenital Cardiovascular Anomalies.)
Tricuspid atresia accounts for 1 to 3% of congenital heart anomalies. The most common type (sometimes referred to as classic tricuspid atresia) includes a ventricular septal defect (VSD) and pulmonic stenosis, which results in decreased pulmonary blood flow, elevated right atrial pressure, and an obligatory right-to-left shunt at the atrial level through a stretched patent foramen ovale or an atrial septal defect (ASD), causing cyanosis (see figure Tricuspid atresia with normally related great vessels). In 12 to 25% of cases, the great arteries are transposed with a VSD and a normal pulmonic valve, with unrestricted pulmonary blood flow coming directly from the left ventricle, typically resulting in heart failure and pulmonary hypertension. Thus, pulmonary blood flow may be increased or decreased.