1. Department of Medical Research, Baerum Hospital, Vestre Viken Hospital Trust, Drammen, Norway;
2. Faculty of Medicine, University of Oslo, Oslo, Norway;
3. Clinic for Medical Diagnostics, Vestre Viken Hospital Trust, Drammen, Norway;
4. Department of Cardiology, Rigshospitalet, University of Copenhagen, Copenhagen Ø, Denmark;
5. Department of Cardiology, Akershus University Hospital, Lørenskog, Norway;
6. Center for Clinical Heart Research, Department of Cardiology, Oslo University Hospital Ullevål, Oslo, Norway