Ebstein anomaly and tricuspid valve disease — formative SAQs

SAQ 1 — The cyanosed neonate with a wall-to-wall heart (10 marks, 15 minutes)

A two-day-old term infant presents with deep central cyanosis that does not improve with supplemental oxygen. On examination the precordium is hyperdynamic, there is a loud scratching pansystolic murmur at the lower left sternal edge, and the liver is palpable four centimetres below the costal margin. The chest X-ray shows a massively enlarged heart with diminished pulmonary vascular markings. A diagnosis of severe Ebstein anomaly with functional pulmonary atresia is suspected. ^[5]

a) Explain why this infant is cyanosed, and why the cyanosis does not improve with oxygen. (3 marks) ^[2]

b) Outline your immediate resuscitation, naming the specific drug, its dose and its mechanism of action. State the most important side effect and how you would manage it during retrieval to a cardiac centre. (5 marks) ^[3]

c) Describe how the neonatal echocardiographic severity is graded, and how the grade changes the surgical plan. (2 marks) ^[10]