1. Department of Medicine and Health Care St. Olavs Hospital, Trondheim University Hospital Trondheim Norway
2. Division Lillehammer, Department of Medicine Innlandet Hospital Trust Lillehammer Norway
3. Norwegian University of Science and Technology, NTNU Trondheim Norway
4. Department of Cardiology, Division of Medicine Stavanger University Hospital Stavanger Norway
5. Department of Electrical Engineering and Computer Science, Faculty of Science and Technology University of Stavanger Stavanger Norway
6. Department of Cardiology, Division of Cardiovascular and Pulmonary Diseases, Oslo University Hospital, Rikshospitalet, and Institute of Clinical Medicine University of Oslo Oslo Norway
7. KG Jebsen Cardiac Research Center and Center for Heart Failure Research Oslo University Hospital Postbox 4956 Nydalen Oslo 0424 Norway