What CHD patterns are typically seen with 22q11.2 deletion?

• A. Atrioventricular septal defect alone
• B. Conotruncal defects such as tetralogy of Fallot, interrupted aortic arch, persistent truncus arteriosus
• C. Isolated VSD
• D. Isolated coarctation

Answer: (B)

22q11.2 deletion is strongly linked to conotruncal heart defects caused by disrupted neural crest cell migration that guides outflow tract and aortic arch development. The classic CHD patterns reflect this failure of truncus arteriosus septation and arch formation, leading to defects like tetralogy of Fallot with pulmonary stenosis, interrupted aortic arch, and persistent truncus arteriosus. This constellation is the hallmark pattern associated with 22q11.2 deletion because it directly mirrors the embryologic disruption of outflow tract formation. While other defects such as isolated VSD or AVSD can occur in various contexts, they are not the characteristic association of this deletion, and isolated coarctation is less specifically linked.