1. Division of Cardiovascular Diseases, Cardio-Thoracic Department, IRCCS–ISMETT, Palermo, Italy
2. Papa Giovanni XXIII Hospital, Bergamo, Italy
3. Ri.MED Foundation, Palermo, Italy
4. Division of Cardiovascular Diseases, University of Palermo, Palermo, Italy
5. Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
6. Division of Cardiovascular Diseases, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
7. Cardiovascular Division, Washington University in St. Louis, St. Louis, MO, USA