1. Department of Cardiac Electrophysiology, Barts Heart Centre, St Bartholomew’s Hospital, London, UK
2. Department of Cardiac Electrophysiology, Barts Heart Centre, St Bartholomew’s Hospital, London, UK; Institute of Cardiovascular Science, University College London, London, UK; Department of Cardiac Electrophysiology, Essex Cardiothoracic Centre, Basildon, UK