1. Research Department, Roding Ward, Essex Cardiothoracic Centre, Mid and South Essex NHS Hospitals Trust, Basildon, UK; Department of Circulatory Health Research, Anglia Ruskin University, Chelmsford, UK
2. Department of Circulatory Health Research, Anglia Ruskin University, Chelmsford, UK; Second Department of Cardiology, Attikon University Hospital, National and Kapodistrian University of Athens Medical School, Athens, Greece