1. Department of Cardiothoracic Surgery, Leiden University Medical Centre, Leiden, Netherlands
2. Department of Cardio-Thoracic Surgery, Erasmus Medical Centre, Rotterdam, Netherlands
3. German Heart Centre, Technical University of Munich, Munich, Germany
4. Deparment of Cardiac Surgery, Québec Heart and Lung Institute, Québec City, Canada
5. Department of Cardiac and Vascular Surgery, University Hospital of Bordeaux, Bordeaux, France
6. Department of Cardiothoracic Surgery, St Thomas’ Hospital, London, UK
7. Department of Cardiothoracic Surgery, ProMedica Toledo Hospital, Toledo, OH, USA
8. Department of Cardiac Surgery, Leipzig Heart Centre, University Hospital, Leipzig, Germany
9. Statistical Services Department, Medtronic, Minneapolis, MN, USA
10. Department of Surgery, University Hospitals, Cleveland Medical Center, Case Western Reserve University School of Medicine, Cleveland, OH, USA