At Mayo Clinic, we take the time to listen, to find answers and to provide you the best care. Congenital heart disease (congenital heart defect) is an abnormality in your heart's structure that you're born with. Although congenital heart disease is often considered a childhood condition, advances in surgical treatment mean most babies who once died of congenital heart disease survive well into adulthood. While medical advances have improved, many adults with congenital heart disease may not be getting proper follow-up care.