what is septal defect of the heart
An atrial septal defect is a birth defect of the heart in which there is a hole in the wall (septum) that divides the upper chambers of the heart (atria). A hole can vary in size and may close on its own or may require surgery.An atrial septal defect is one type of congenital heart defect.n atrial septal defect is a birth defect of the heart in which there is a hole in the wall (septum) that divides the upper chambers of the heart (atria). A hole can vary in size and may close on its own or may require surgery.