1. First Department of Surgery, National and Kapodistrian University of Athens, Laikon General Hospital, Athens, Greece
2. 251 VA and Hellenic Air Force Hospital, Athens, Greece
3. Department of Medicine, Jacobi Medical Center, Albert Einstein College of Medicine, Bronx, New York, USA
4. Division of Cardiology, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
5. Division of Surgery, Department of Clinical Science Intervention and Technology and Department of Upper Abdominal Diseases, Karolinska Institutet, Stockholm, Sweden