1. Electrophysiology Department, Barts Heart Centre, St. Bartholomew’s Hospital, West Smithfield, London EC1A 7BE, UK
2. Institute of Cardiovascular Science, University College London, Gower St, London WC1E 6BT, UK
3. Cardiology Department, Royal Brompton Hospital, Sydney St, SW3 6NP, London, UK
4. Division of Electrophysiology, Department of Cardiovascular Medicine, University Hospital of Münster, Albert-Schweitzer-Campus 1, 48149, Münster, Germany