A 3-year-old child is found to have fixed splitting of the second heart sound (S2), a soft ejection systolic murmur at the upper left sternal border, and increased pulmonary vascular markings on chest X-ray. What is the MOST likely congenital heart defect?

• A Ventricular septal defect
• B Pulmonary stenosis
• C Coarctation of aorta
• D Atrial septal defect ✓

Explanation

Fixed splitting of the second heart sound is the hallmark auscultatory finding of atrial septal defect. The split is fixed (does not vary with respiration) because equalization of atrial pressures occurs throughout the respiratory cycle. The ejection systolic murmur is due to increased flow across the pulmonary valve (relative pulmonary stenosis), and the right heart volume overload causes increased pulmonary vascular markings. ASD is the most common CHD presenting in adulthood.

Reference: Ghai Essential Pediatrics, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.