King’s College London - Division of Biomedical Engineering and Imaging Sciences, University of Cambridge - School of Clinical Medicine, Hospital Sant Joan de Deu - Department of Pediatric Cardiology, King’s College London - Department of Women and Children’s Health, Government of the United Kingdom - Birmingham Women’s and Children’s NHS Foundation Trust, University of Lyon Medical Center - Department of Paediatric Cardiology, Medical University of Warsaw - Department of Pediatric Cardiology, Hospital Vittore Buzzi -Asst Fbf Sacco, Hospital Infantil Universitario Niño Jesus - Department of Paediatric Cardiology, Hospital La Paz - Department of Paediatric Cardiology, Royal Manchester Childrens Hospital - Paediatric Cardiology, Ghent University Hospital - Department of Paediatric Cardiology, University Hospitals Bristol and Weston NHS Foundation Trust - Department of Paediatric Cardiology, CHI - Department of Paediatric Cardiology, Papa Giovanni XXIII Hospital - Department of Pediatric Cardiology, Regina Margherita Children's Hospital - Pediatric Cardiac Surgery, Alder Hey Children's Hospital - Department of Paediatric Cardiology, IRCCS Istituto Giannina Gaslini - Paediatric Cardiology and Pediatric Rheumatology Clinic, Leeds Children's Hospital - Department of Paediatric Cardiology, Glenfield Hospital - Department of Paediatric Cardiology, Royal Hospital for Children - Department of Paediatric Cardiology,, Bambino Gesù Children's Hospital - Cardiac Surgery Department, Centre Hospitalier Universitaire Toulouse, Leuven University Hospital - Department of Pediatric and Congenital Cardiology, Amsterdam UMC - Department of Pediatric Cardiology, Centro Hospitalar Lisboa Ocidental - Paediatric Cardiology Department, University of Bologna - Pediatric Cardiology, University Hospital Southampton - Department of Paediatric Cardiology, Newcastle upon Tyne Hospitals NHS Foundation Trust - Department of Paediatric Cardiology, AO SS Antonio e Biagio e C. Arrigo - Pediatric Cardiology service, Universitair Ziekenhuis Brussel - Department of Pediatric Cardiology, Centro Hospitalar Universitário Lisboa Norte - Paediatric Department, Emergency Children's Hospital, Hospital Universitari Vall d´Hebron Barcelona, Hospital General Universitario Gregorio Marañon Madrid - Pediatric Cardiology Section, Hospital Materno Infantil Malaga - Department of Paediatric Cardiology, Mother and Child Health Institute of Serbia - Cardiology Department, Oxford University Hospitals NHS Foundation Trust - Department of Paediatric Cardiology, University of Padua - Pediatric Cardiology Unit, Antwerp University Hospital - Department of Paediatric Cardiology, Institute of Biomedicine IBIS - Department of Paediatric Cardiology, University Children's Hospital - Department of Paediatric Cardiology, Coimbra's University Hospital Center - Department of Pediatric Cardiology, CHU de Liège - Service de Pédiatrie, Centre Hospitalier Chrétien - Paediatric Department, Hospital Puerta del Mar - Paediatric Cardiology Unit, A Coruña University Hospital, University Children's Hospital - Department of Paediatric Cardiology, San Bortolo Hospital - Paediatric Intensive Care Unit, "Louis Turcanu" Emergency Hospital for Children - Department of Paediatric Cardiology, Medical University Graz - Division of Pediatric Cardiology, Univerity Hospital - Pediatric Department and Intensive Care Unit, Oslo University Hospital - Department of Paediatric Cardiology, Río Hortega University Hospital - Paediatric Cardiology Unit, Centro Hospitalar Universitario Lisboa Central (CHULC) - Department of Pediatric Cardiology, Turku University Hospital - Department of Pediatry and Guy's and St Thomas' NHS Foundation Trust - Department of Congenital Heart Disease