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Tetralogy of Fallot Pulmonary Stenosis Pulmonary Atresia Tricuspid Atresia Ebstein's Anomaly

Pulmonary Atresia

  • Pulmonary atresia refers to the condition where the right ventricular outflow through the pulmonary artery is completely obstructed by fusion of the pulmonary valve leaflets.
  • This condition may occur in the presence or absence of a ventricular septal defect.
    • Pulmonary atresia with intact ventricular septum is characterized by the right ventricle and tricuspid valve varying in size from near normal to miniscule. It is most often associated with coronary artery abnormalities including atresia of aortic origins or obstruction and occlusion, among others.
      • For blood to exit the right ventricle, it must either return to the right atrium via the tricuspid valve or drain into the coronary circulation.
        Initially, venous return to the right atrium passes through the patent foramen ovale to the left atrium then left ventricle. The ductus arteriosus supplies blood to the lungs for the first few days after birth and is sufficient for survival. When the ductus closes, however, atresia of the pulmonary valve prevents blood flow to the lungs and survival is impossible.
      • Infants with this defect are cyanotic at birth and will display varying levels of respiratory distress depending on the amount of oxygen in the arterial blood supply.
      • Pulmonary atresia with intact ventricular septum is initially managed by providing pulmonary blood flow through the patent foramen ovale which is maintained by administering prostaglandin E. Surgery may then performed to place a right ventricular outflow patch and shunt that ensures ongoing blood flow through the pulmonary circuit.