1. Department of Cardiology Copenhagen University Hospital, Rigshospitalet Copenhagen Denmark
2. Department of Medical Sciences, Cardiology Uppsala University Uppsala Sweden
3. Department of Medicine, Heart and Vascular Theme, Karolinska University Hospital Karolinska Institutet Stockholm Sweden
4. Heart and Lung Center Helsinki University Central Hospital Helsinki Finland
5. Helsinki University Helsinki Finland
6. Department of Cardiology, Sahlgrenska Academy University of Göteborg Gothenburg Sweden
7. Department of Cardiology, Rikshospitalet Oslo University Hospital Oslo Norway
8. Faculty of Medicine University of Oslo Norway
9. Department of Surgery and Perioperative Sciences Umeå University Umeå Sweden
10. Department of Cardiology Lund University Hospital Lund Sweden
11. Department of Cardiology Haukeland University Hospital Bergen Norway