1. Research Unit of Internal Medicine, University Hospital of Oulu and University of Oulu, PO Box 5000, Oulu FIN-90014, Finland
2. Division of Cardiology, Heart and Lung Center, Helsinki University Central Hospital, PO Box 340, Helsinki FIN-00029, Finland
3. Department of Forensic Medicine, Institute of Diagnostics, University of Oulu, PO Box 5000, Oulu FIN-90014, Finland