Atrial septal defect is a common congenital heart defect. Its anatomical types differ in location and associated valve abnormalities.
Frequency
•
Atrial septal defect is one of the most common congenital heart defects and occurs twice as frequently in females.
Anatomical distinctions
•
Most are ostium secundum defects involving the fossa ovalis, which was the foramen ovale in utero.
•
Ostium primum defects arise from a defect in the atrioventricular septum and are associated with a cleft mitral valve, described as a split anterior leaflet.