1. Cardiac, Thoracic and Vascular Department; University of Pisa; Pisa Italy
2. Division of Cardiology, University of Perugia; School of Medicine; Perugia Italy
3. Department of Internal Medicine; University of Perugia; Perugia Italy
4. Cardiac, Thoracic and Vascular Department; Fondazione IRCCS; Policlinico San Matteo Pavia Italy
5. Institute of Clinical Physiology; National Research Council; Pisa Italy
6. Department of Biomedical and Surgical Sciences; Cardiology Section, University of Verona; Verona Italy
7. Division of Cardiology, Fondazione Salvatore Maugeri; IRCCS; Veruno Italy