1. Department of Cardiothoracic Surgery, St Antonius Hospital, Nieuwegein, The Netherlands
2. Department of Cardiac Surgery, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy
3. Department of Cardiac Surgery, Radboud University Medical Center, Nijmegen, The Netherlands
4. Department of Cardiothoracic Surgery, Academic Medical Center, Amsterdam, The Netherlands