1. Department of Cardiology, National Heart and Lung Institute, Faculty of Medicine, Imperial College London, UK
2. Department of Cardiology, National Heart & Lung Institute, Faculty of Medicine, Imperial College London, UK, Cardiology Department, Royal Brompton & Harefield Hospital NHS Foundation Trust London SW3 6NP, UK
3. Cardiology and Aortic Centre, Royal Brompton & Harefield Hospital NHS Foundation Trust, London SW3 6NP, UK, Department of Cardiology, National Heart and Lung Institute, Faculty of Medicine, Imperial College London, UK