1. Division of Cardiac Surgery, Department of Surgery Yale School of Medicine New Haven Connecticut USA
2. Cardiac Surgery Unit, Department of Cardiac, Thoracic and Vascular Sciences University Hospital of Padua Padua Italy
3. Division of Minimally Invasive and Robotic Cardiac Surgery, Department of Surgery University of Chicago Chicago Illinois USA
4. International School of Cardiac Surgery Ettore Majorana Foundation and Center for Scientific Culture Erice Italy