A newborn with Down syndrome (trisomy 21) is examined. Besides the characteristic dysmorphic features, which cardiac defect is MOST COMMONLY associated with Down syndrome?

• A Ventricular septal defect (VSD)
• B Patent ductus arteriosus (PDA)
• C Atrioventricular septal defect (AVSD) — complete type ✓
• D Tetralogy of Fallot

Explanation

While VSD is the most common CHD in the general population, complete atrioventricular septal defect (AVSD, also called endocardial cushion defect or AV canal defect) is the defect most characteristically and specifically associated with Down syndrome, occurring in approximately 40–50% of Down syndrome patients with CHD. It involves a primum ASD, inlet VSD, and common AV valve. PDA is common in prematurity. Tetralogy of Fallot has a weaker association with Down syndrome.

Reference: Ghai Essential Pediatrics, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.