Educational Content: This article is for informational purposes only and does not constitute medical advice. Always consult a healthcare provider for diagnosis and treatment.
Definition of Defect, atrial septal (ASD)
Medically reviewed by Min Clinic Staff | Updated: January 2026
Defect, atrial septal (ASD): A hole in the septum, the wall, between the atria, the upper chambers of the heart. Commonly called an ASD. ASDs are a major class of congenital cardiac malformation.