1. Department of Clinical, Internal, Anesthesiology and Cardiovascular Sciences, Umberto I Hospital, Sapienza University of Rome, Viale del Policlinico 155 (Emodinamica A, Ottavo Padiglione, II Piano), 00161 Rome, Italy
2. Department of Medical Science, Division of Cardiology, Molinette Hospital, Turin University, 10124 Turin, Italy