Cardiology Division, Ospedale Garibaldi-Nesima, Azienda di Rilievo Nazionale e Alta Specializzazione 'Garibaldi' Catania, Italy. ANMCO Research Center of the Heart Care Foundation, Via La Marmora, 36, Firenze, Italy. Cardiology Division, San Maurizio Regional Hospital of Bolzano, Bolzano, Italy. UOC Cardiologia-UTIC, San Filippo Neri Hospital, Rome, Italy. Division of Cardiology, San Giovanni Evangelista Hospital, Tivoli, Italy. Cardiovascular Center, Azienda Sanitaria Universitaria Integrata di Trieste, Trieste, Italy. Cardiology Division, Department of Diagnostics, Clinical and Public Health Medicine, University of Modena and Reggio Emilia, Policlinico di Modena, Modena, Italy. Division of Cardiology, Maggiore Hospital, Bologna, Italy. Unit of Cardiology, S. Spirito Hospital, Casale Monferrato, Italy. Interventional Cardiology-CCU Department, G. Rummo Hospital, Benevento, Italy.