[1] Univ Padua, Div Cardiac Surg, Padua, Italy
[2] Univ Padua, Div Biostat, Padua, Italy
[3] San Gaudenzio Hosp, Div Cardiac Surg, Novara, Italy
[4] Osped Cuore G Pasquinucci, Div Cardiac Surg, Massa, Italy
[5] Ctr Cardiol Monzino, Dept Cardiac Surg, Milan, Italy
[6] Catholic Univ, Policlin Univ Agostino Gemelli, Dept Cardiac Surg, Rome, Italy
[7] Osped Riuniti, Dept Cardiac Surg, Ancona, Italy
[8] Papa Giovanni XXIII Hosp, Dept Cardiac Surg, Bergamo, Italy
[9] Univ Udine, Dept Cardiac Surg, S Maria Misericordia Hosp, Udine, Italy
[10] LAngelo Hosp, Dept Cardiac Surg, Venice, Italy
[11] GB Morgagni L Pierantoni Hosp, Dept Cardiac Surg, Catania, Italy
[12] Osped Niguarda Ca Granda, Dept Cardiac Surg, Milan, Italy
[13] Univ Hosp Turin, Dept Cardiac Surg, Turin, Italy
[14] European Hosp, Dept Cardiac Surg, Rome, Italy
[15] Univ Hosp Bologna, Dept Cardiac Surg, Bologna, Italy
[16] San Carlo Hosp, Dept Cardiac Surg, Potenza, Italy
[17] Sacco Hosp, Dept Cardiac Surg, Milan, Italy
[18] San Bortolo Hosp, Dept Cardiac Surg, Vicenza, Italy
[19] San Camillo Hosp, Dept Cardiac Surg, Rome, Italy
[20] St Anna Hosp, Dept Cardiac Surg, Catanzaro, Italy
[21] Univ Hosp Pisa, Dept Cardiac Surg, Pisa, Italy
[22] Santissima Annunziata Hosp, Dept Cardiac Surg, Sassari, Italy
[23] San Raffaele Univ Hosp, Dept Cardiac Surg, Milan, Italy
[24] Giovanni Paolo II Hosp, Dept Cardiac Surg, Campobasso, Italy