1. Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DU, UK.
2. Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, OX3 7LE, UK.
3. Department of Cardiothoracic Surgery, Oxford University Hospitals NHS Trust, Oxford, OX3 9DU, UK.
4. Bristol Medical School, University of Bristol, Research Floor Level 7, Bristol Royal Infirmary, Bristol BS2 8HW, UK.
5. Cardiology Department, Athens University Medical School, Athens 115 27, Greece.