1 Paediatric Cardiology Services, Royal Brompton Hospital and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom. Electronic address: a.fraisse@rbht.nhs.uk.
2 Paediatric Cardiology Services, Royal Brompton Hospital and Harefield National Health Service Foundation Trust, London, United Kingdom; Adult Congenital Heart Disease Unit, Royal Brompton Hospital and Harefield National Health Service Foundation Trust, London, United Kingdom.
3 Paediatric Cardiology Services, Royal Brompton Hospital and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom. Electronic address: https://twitter.com/carlesbautista.