[1] Essex Cardiothorac Ctr, Cardiol Dept, Basildon SS16 5NL, England
[2] Anglia Ruskin Univ, Sch Med, Chelmsford CM1 1SQ, England
[3] Univ Athens, Univ Hosp Attikon, Cardiol Dept 2, Haidari 12462, Greece
[4] 401 Gen Mil Hosp Athens, Cardiol Dept, Athens 11525, Greece
[5] UniCamillus St Camillus Int Univ Hlth Sci, S Giovanni Hosp, Cardiol Dept, I-00131 Rome, Italy
[6] Barts Hlth NHS Trust, Barts Heart Ctr, Dept Cardiol, West Smithfield, London EC1A 7BE, England
[7] Queen Mary Univ London, William Harvey Res Inst, Ctr Sports & Exercise Med, 327 Mile End Rd, London E1 4NS, England
[8] UCL, Inst Cardiovasc Sci, Gower St, London WC1E 6BT, England