An atrial septal defect (AFD) is a hole in the wall (septum) between the two upper chambers of your heart (Atria). The defect is already present at birth (congenital).
Small defects can be detected accidentally and may never cause problems. Sometimes small atrial septal defects are closed in infancy or early childhood. Defect-the hole increases the amount of blood flowing through the lungs. A large and long-standing atrial septal defect can lead to damage to the heart and lungs. To eliminate atrial septal defects and prevent complications, open surgery or endovascular closure of the defect with a special occluder device may be required.