1. Department of Cardiology; Herlev & Gentofte Hospital, University of Copenhagen; Niels Andersensvej 65, Post 835 DK-2900 Copenhagen Denmark
2. Institute of Clinical Medicine, Faculty of Health Sciences; University of Copenhagen; Copenhagen Denmark
3. Clinical Institute; Aalborg University; Aalborg Denmark
4. Cardiovascular Medicine Division; Brigham and Women's Hospital, Harvard Medical School; Boston MA USA