How much can atrial septal defect heal itself?

Atrial septal defect (ASD) is a congenital heart disease that can heal spontaneously if the defect is less than 5 mm. In children with ASD, small heart defects normally heal before one and a half years of age. If they do not heal after one and a half years of age, they generally do not need special treatment. They can be closely observed at ordinary times.