1. Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center, University Hospital Essen , Essen, Germany
2. Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC) , Berlin, Germany
3. Charité—Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin , Berlin, Germany
4. Department of Cardiovascular and Thoracic Surgery, Faculty of Medicine, Johannes Kepler University Linz , Linz, Austria
5. Department of Cardiovascular and Thoracic Surgery, Wels-Grieskirchen Clinic , Wels, Austria
6. Clinic of Cardiac Surgery, University Hospital Oldenburg, Oldenburg, Germany
7. Department of Heart and Vascular Surgery, University Medical Center of the Johannes Gutenberg-University Mainz , Mainz, Germany
8. Department of Cardiac Surgery, IRCCS San Raffaele Hospital, Vita-Salute San Raffaele University , Milan, Italy
9. Division of Cardiothoracic Surgery, Department of Cardiothoracic Surgery, the Chinese University Hong Kong , Hong Kong
10. Department of Cardiac Surgery, District Hospital No. 2, University of Rzeszów , Rzeszów, Poland
11. Departemnt of Cardiac Surgery, Kerckhoff-Clinic, Campus Kerckhoff, University of Gießen , Bad Nauheim, Germany
12. University Department of Cardiac Surgery, Heart Center Leipzig , Leipzig, Germany
13. St Bartholomew’s Hospital, Barts Health NHS Trust , London, UK
14. Department of Cardiovascular Surgery, University Hospital Frankfurt, Goethe University , Frankfurt, Germany
15. Department of Cardiothoracic Surgery, Heart Center of the University of Cologne , Cologne, Germany
16. Department of Cardiovascular Surgery, University Hospital Álvaro Cunqueiro , Vigo, Spain
17. Department of Cardiovascular Surgery, Clinic Floridsdorf , Vienna, Austria
18. Institute of Cardiovascular Research, Karl Landsteiner Society , Vienna, Austria
19. Medical Faculty, Sigmund Freud Private University , Vienna, Austria