Atrial septal defect (ASD)
Disease Information
In-Depth
Atrial septal defects occur in 5 to 10 percent of all children born with a congenital heart defect. Girls have atrial septal defects twice as often as boys.
What are the symptoms of an atrial septal defect?
Small or medium sized defects may not produce any symptoms in children. Some symptoms that may occur in children can include:
- difficulty breathing (dyspnea)
- frequent respiratory infections
- shortness of breath
How did my child get an atrial septal defect?
During the first eight weeks of fetal development, the heart forms. It begins as a hollow tube, then partitions develop within the tube that eventually become the walls that divide the right side of the heart from the left. Atrial septal defects occur when the partitioning process doesn’t complete, leaving an opening in the atrial septum.
Most atrial septal defects are not genetic. Instead, they occur by chance, with no clear reason for their development.
What are the risks associated with an atrial septal defect?
An atrial septal defect allows oxygen-rich (red) blood to pass from the left atrium through the opening in the septum, and then mix with oxygen-poor (blue) blood in the right atrium. A child with an ASD is at an increased risk for developing a number of complications including:
- atrial fibrillation
- heart failure
- pulmonary overcirculation
- pulmonary hypertension
- stroke
