1. Medical University of Vienna, Vienna, Austria
2. Royal Prince Alfred Hospital
3. Institute of Academic Surgery at Royal Prince Alfred Hospital
4. The Baird Institute of Applied Heart and Lung Surgical Research, Sydney
5. Medical School, University of Sydney, Camperdown, New South Wales, Australia
6. University Department of Cardiac Surgery, Leipzig Heart Center, Leipzig
7. Charité Universitätsmedizin Berlin
8. Deutsches Herzzentrum der Charité (DHZC), Department of Cardiothoracic and Vascular Surgery, Berlin
9. Justus Liebig University Giessen
10. Hospital de Cruces, Barakaldo
11. Swiss Heart Clinic, Zurich
12. Kerckhoff Heart Center Bad Nauheim, Campus Kerckhoff Justus-Liebig University Giessen, Giessen
13. Montreal Heart Institute, Montreal, Canada
14. Manavgat Government Hospital, Manavgat
15. Bahçeşehir University Faculty of Medicine, Istanbul, Turkey
16. Hospital General Universitario Gregorio Marañón
17. Hospital Universitario Ramon y Cajal, Madrid
18. European Hospital, Rome, Italy
19. German Heart Center Munich, Munich
20. Yale University School of Medicine, New Haven, Connecticut
21. Hospital Universitario de Salamanca, Salamanca, Spain
22. Hospital Universitario Virgen Macarena, Seville
23. University Hospital Frankfurt, Frankfurt, Germany
24. Cardiocentro Ticino Institute, EOC, Lugano, Switzerland
25. Boston University
26. Boston Clinical Research Institute (BCRI), Boston, Massachusetts, USA