1. St George's, University of London , London SW17 0RE , UK
2. St George's University Hospitals NHS Foundation Trust , Blackshaw Rd, London SW17 0QT , UK
3. Department of Cardiology, Glenfield Hospital , Leicester , UK
4. Department of Cardiology, University Hospital of Wales , Cardiff , UK
5. Department of Cardiology, Frimley Park Hospital , London , UK
6. Department of Cardiology, Guy’s and St Thomas’s Hospital , London , UK
7. Department of Cardiology, Royal Brompton and Harefield NHS Foundation Trust , London , UK
8. Institute of Sport, Manchester Metropolitan University and University of Manchester , Manchester , UK