Atrial Septal Defects

Atrial septal defects (ASD)managementAtrial septal defects (ASDs) are a group of congenital heart lesions where there is a communication between the right and left atriums. These lesions will lead to increased pulmonary blood flow unless there are associated lesions or complications preventing excessive pulmonary blood flow. Atrial septal defect is commonly encountered as a solitary lesion or may present in association with other congenital heart defects. Isolated ASDs present with clinical features secondary to increase in pulmonary blood flow. At older age, and due to chronic increase in pulmonary blood flow, it can cause increased pulmonary vascular resistance and as a result pulmonary hypertension, which precipitates right to left shunting at the atrial septal defect, causing cyanosis or stroke. Management of ASD, particularly in infants, is initially that of observation, as many spontaneously close. Defects which continue to be present beyond 3–5 years of age require closure. Until 1–2 decades ago, all ASD cases were referred for surgical closure; however, nowadays secundum ASDs are closed through devices in the catheterization laboratory, while those who are not amenable to device closure, such as large defects, sinus venosus ASDs, and primum ASDs are repaired through surgery. Atrial septal defects in complex congenital heart defects assist in maintaining adequate cardiac output and are as such desirable since they provide means of egress of blood flow, such as with tricuspid atresia, hypoplastic left heart syndrome, and other lesions. In these cases, an initial patent foramen ovale may be enlarged through balloon rupture of the atrial septum (Rashkind procedure) or surgically to allow for an unobstructed pathway for blood to cross. This chapter reviews the various types of atrial septal defect and their presentation and management in the pediatric population of patients. Other chapters within this textbook discuss atrial septal defects in the adult population and those associated with more complex lesions.