1. Department of Cardiology, University Medical Center Groningen; University of Groningen; Groningen The Netherlands
2. Erasmus MC Thoraxcenter; Rotterdam The Netherlands
3. Department of Cardiology; King's College Hospital; London UK
4. Department of Cardiology; Attikon University Hospital; Athens Greece
5. Department of Cardiology, Clinic for Cardiology; University Hospital Zurich; Zurich Switzerland
6. Department of Cardiology, University Medical Center Utrecht; University of Utrecht; Utrecht the Netherlands