1. Department of Cardio-Thoracic Surgery, Erasmus Medical Center, Rotterdam, The Netherlands
2. Department of Cardio-Thoracic Surgery, St. Antonius Hospital, Nieuwegein, The Netherlands
3. Department of Cardio-Thoracic Surgery, University Medical Center Leiden/Academic Medical Center, Amsterdam, The Netherlands
4. Department of Cardio-Thoracic Surgery, University Medical Center Nijmegen, Nijmegen, The Netherlands
5. Department of Cardio-Thoracic Surgery, University Medical Center Utrecht, Utrecht, The Netherlands
6. Department of Cardio-Thoracic Surgery, University Medical Center Groningen, Groningen, The Netherlands