1. Department of Cardiology, Cardiovascular Research Institute Maastricht, Faculty of Health, Medicine, and Life Sciences, Maastricht University, PO Box 616, Maastricht 6200, The Netherlands
2. Department of Cardiology, J. W. Goethe-Universität Frankfurt am Main, Frankfurt/Main, Germany
3. Cardiovascular and Cell Sciences Research Institute, Cardiology Clinical Academic Group, St George's, University of London, London, UK