1. Department of Cardiology, Copenhagen University Hospital, Rigshospitalet , Blegdamsvej 3, 2100 Copenhagen , Denmark
2. Department of Cardiology, Copenhagen University Hospital, Herlev and Gentofte Hospital, Hospitalsvej 1 , 2820 Gentofte , Denmark
3. Department of Anesthesiology, Copenhagen University Hospital, Herlev and Gentofte Hospital, Herlev, Borgmester Ibs Juuls vej 1, 2730 Herlev , Denmark
4. Department of Cardiology, Aalborg University Hospital , Hobrovej 18-22, 9000 Aalborg , Denmark
5. Department of Cardiology, Nordsjællands Hospital , 3400 Hillerød , Denmark
6. Department of Public Health, University of Copenhagen , 1165, Copenhagen Denmark
7. Department of thoracic surgery, Copenhagen University Hospital, Rigshospitalet , Blegdamsvej 3, 2100 Copenhagen , Denmark