1. University Heart Center Freiburg—Bad Krozingen, Faculty of Medicine, Albert Ludwigs University Freiburg, Freiburg, Germany
2. Policlinico S.Orsola-Malpighi, Bologna, Italy
3. Dupuytren University Hospital, Limoges, France
4. Golden Jubilee National Hospital, University of Glasgow, Glasgow, UK
5. Cardioangiologic Center Bethanien, Frankfurt, Germany
6. Hospital Val D’Hebron, Barcelona, Spain
7. Heart Center Hietzing, Vienna, Austria
8. Department of Advanced Biomedical Sciences, University of Napoli “Federico II”, Naples, Italy
9. Department of Cardiac Surgery, Rzeszów, Poland
10. Department of Cardiac, Thoracic and Vascular Surgery, University of Tübingen, Tübingen, Germany
11. Department of Cardiology, Humanitas Gavazzeni, Bergamo, Italy
12. Cardiovascular Surgery, University of Brescia, Brescia, Italy
13. Department of Cardiology, Royal Brompton Hospital, London, UK
14. Department of Cardiac Surgery, European Hospital, Rome, Italy
15. West German Heart Center, Essen, Germany