1. Department of Cardiothoracic Surgery, James Cook University Hospital, South Tees NHS Foundation Trust , Middlesbrough , United Kingdom
2. Department of Cardiology, Emergency Clinical Hospital , Bucharest , Romania
3. Department of Cardiology, Morriston Cardiac Centre, Swansea Bay University Health Board , Swansea , United Kingdom
4. Department of Adult and Paediatric Cardiac Surgery, Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust , Bristol , United Kingdom