1 University College London, London, United Kingdom; St Bartholomew's Hospital, London, United Kingdom. Electronic address: [email protected].
2 Michael DeGroote Heart and Stroke Chair in Population Health and Epidemiology, McMaster University, Hamilton, Ontario, Canada.
3 Vanderbilt Translational and Clinical Cardiovascular Research Center, Division of Cardiovascular Medicine, Vanderbilt University, Nashville, Tennessee, USA.