1. Department of Cardiology, The Heart Hospital, University College London Hospital, London, England
2. Department of Cardiology, Guy’s and St Thomas’ Hospital, London, England
3. Department of Cardiology, Royal Free Hampstead National Health Service Trust, London, England
4. Department of Cardiology, King’s College Hospital, London, England
5. Department of Cardiology, St George’s Hospital, London, England
6. Department of Cardiology, Barts Health National Health Service Trust, London, England
7. Department of Statistics, Technische Universität Dortmund, Dortmund, Germany
8. Department of Cardiology, Harefield Hospital, London, England
9. Department of Cardiology, Imperial College Healthcare National Health Service Trust, London, England