Atrial septal defect (ASD). Oxygenated blood from the left atrium shunts via this hole into the right atrium. This volume load causes enlargement of both atria, the right ventricle and the pulmonary artery.
Patch closure of atrial septal defect. Many defects may be closed using a primary suture technique. Patches are used in larger defects. Catheter delivered device closure is currently being evaluated investigationally.