An atrial septal defect (ASD) — sometimes called a hole in the heart — is a type of congenital heart defect in which there is an abnormal opening in the dividing wall between the upper filling chambers of the heart (the atria).
In most cases, ASDs are diagnosed and treated successfully with few or no complications.
The size of an ASD and its location determine the symptoms it causes. Most kids who have ASDs seem healthy and appear to have no symptoms. Most feel well, and grow and gain weight normally.
An ASD that isn’t treated in childhood can lead to health problems later, including an abnormal heart rhythm (an atrial arrhythmia) and problems in how well the heart pumps blood. As kids with ASDs get older, they also might be at an increased risk for stroke because a blood clot could form, pass through the hole in the septum, and travel to the brain. Pulmonary hypertension (high blood pressure in the lungs) also may develop over time in older patients with larger untreated ASDs.