Interpret a paediatric echocardiogram report — OSCE

A six-year-old boy is referred to the paediatric clinic after a GP heard a heart murmur at a school check. He is asymptomatic, active, and growing normally. The GP arranged a comprehensive paediatric echocardiogram, the report of which is placed in front of you. It describes a bicuspid aortic valve, a peak continuous-wave Doppler velocity of 4 metres per second across the valve, a left ventricular end-diastolic dimension with a Z-score of 0.8, a normal aortic root, and normal left ventricular systolic function with a fractional shortening of 34 percent. You are the paediatric registrar asked to interpret the report, calculate the valve gradient, give the differential and the disposition, and outline how you would resuscitate a duct-dependent neonate if asked.