Ebstein anomaly and tricuspid valve disease — branching viva

Stage 1 — The cyanosed neonate

The examiner shows you a two-day-old cyanosed neonate with a wall-to-wall heart on chest X-ray and a loud tricuspid regurgitant murmur. The oxygen saturation is sixty percent and does not rise with supplemental oxygen. ^[5]

• What is your working diagnosis, and what bedside and radiographic features support it? Severe Ebstein anomaly with functional pulmonary atresia, supported by the huge heart, oligoaemic lungs, the murmur and oxygen-unresponsive cyanosis. ^[5]

• What drug do you start immediately, at what dose, and why does it work? Prostaglandin E1 at 0.01 to 0.05 micrograms per kilogram per minute; it keeps the ductus arteriosus open to supply pulmonary blood flow while the pulmonary vascular resistance falls. ^[3]

• What is the most dangerous side effect, and how do you manage it in transfer? Apnoea; the baby must travel intubated or with airway expertise. ^[3]

Stage 2 — The fetus with hydrops

The examiner moves to the antenatal clinic. A twenty-four-week fetus has Ebstein anomaly with ascites and skin oedema. ^[10]

• How is fetal and neonatal severity graded, and what does the grade predict? The Great Ormond Street Echocardiography score grades severity one to four; scores of three and four and the presence of hydrops predict high mortality. ^[10]

• What is the significance of hydrops, and what prenatal intervention may be considered? Hydrops carries the gravest prognosis; prenatal non-steroidal anti-inflammatory therapy may close a circular shunt and reverse hydrops in a specialist fetal centre. ^[3]