Overview Snapshot A 24-hour newborn appears blue in all extremities, is cyanotic, and is transferred immediately to the NICU, where he is found to have a single, loud S2 murmur. Introduction Anatomic anomaly where the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle leads to pulmonary and systemic circulation existing in parallel Infant must have collateral arteriovenous communication to be compatable with life patent ductus arteriosus (PDA) persistent foramen ovale (PFO) atrial or ventricular septal defect Risk factors are Down's syndrome Apert's syndrome cri-du-chat, trisomy 13/18 Presentation Symptoms newborns are extremely cyanotic (blue skin) and are critically ill Physical exam cyanosis tachypnea progressive respiratory failure early digital clubbing may have no murmur, but a single, loud S2 is characteristic patent ductus arteriosus can lead to characteristic machine like murmur patent foramen ovale has no associated murmur low O2 saturation O2 sat on the right arm will demonstrate a lower preductal saturation than the postductal saturation taken on the lower extremity Evaluation CXR show enlarged egg-shaped heart, often referred to as "egg on a string" due to narrowing of superior mediastinum and convexity of atrial borders Echocardiogram is gold standard for diagnosis Catheterization/MRI may be needed in cases where anatomy is unclear prior to surgery Differential Large VSD, aortic coarctation, tetralogy of fallot, hypoplastic left ventricle Treatment Prostaglandin E1 (PGE1) used to keep PDA open until surgical repair is possible Balloon atrial septostomy (Rashkind procedure) must be performed if immediate surgery is not feasible allow oxygenated blood to travel between the ventricles to get to the aorta. Surgical correction indicated in order for survival can perform either arterial or atrial switch Prognosis, Prevention, and Complications Condition is fatal without correction unless patient has a PDA or VSD