Which heart defect is most commonly associated with Down syndrome?

Which heart defect is most commonly associated with Down syndrome?

• A. Atrial septal defect
• B. Atrioventricular septal defect
• C. Patent ductus arteriosus
• D. Ventricular septal defect

Answer: (B)

Down syndrome greatly increases the likelihood of congenital heart disease, and the defect most characteristically linked to it is an atrioventricular septal defect. This arises from improper development and fusion of the endocardial cushions that form the junction between the atria and ventricles and the valves between them. The classic result is a primum-type atrial septal defect with an inlet-type ventricular septal defect and a common AV valve, sometimes described as an endocardial cushion defect or complete AV canal. This pattern—an AV septal defect—is more typical in Down syndrome than isolated atrial or ventricular septal defects or patent ductus arteriosus, which explains why it’s the best answer.

Down syndrome greatly increases the likelihood of congenital heart disease, and the defect most characteristically linked to it is an atrioventricular septal defect. This arises from improper development and fusion of the endocardial cushions that form the junction between the atria and ventricles and the valves between them. The classic result is a primum-type atrial septal defect with an inlet-type ventricular septal defect and a common AV valve, sometimes described as an endocardial cushion defect or complete AV canal. This pattern—an AV septal defect—is more typical in Down syndrome than isolated atrial or ventricular septal defects or patent ductus arteriosus, which explains why it’s the best answer.