1. Department of Cardiology, Thoraxcenter; University Medical Centre Groningen, University of Groningen; PO Box 30.001, 9700 RB Groningen The Netherlands
2. Julius Centre for Health Sciences and Primary Care; University Medical Centre Utrecht; Utrecht The Netherlands
3. Trial Coordination Centre, University Medical Centre Groningen; University of Groningen; Groningen The Netherlands
4. Department of Cardiology; Atrium Medical Centre; Heerlen The Netherlands