An acyanotic 6-month-old infant has failure to thrive and recurrent chest infections. There is a loud ejection systolic murmur at the upper left sternal border with a palpable thrill and a widely split S2 whose pulmonary component is soft and delayed. Echocardiography would MOST likely show:

• A Patent ductus arteriosus with aortopulmonary window
• B Large ventricular septal defect with pulmonary hypertension
• C Severe valvar pulmonary stenosis with post-stenotic dilatation of the main pulmonary artery ✓
• D Tetralogy of Fallot with severe infundibular stenosis

Explanation

Valvar pulmonary stenosis produces a harsh ejection systolic murmur maximal at the upper left sternal border radiating to the back, an ejection click, and post-stenotic dilatation of the pulmonary trunk on imaging. The delayed soft pulmonary component reflects prolonged RV ejection through the stenosed valve. Tetralogy of Fallot would present with cyanosis and a right-to-left shunt, while a VSD gives a pansystolic rather than ejection systolic murmur.

Reference: Park's Pediatric Cardiology for Practitioners, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.