[1] S Maria Misericordia Univ Hosp Udine, Azienda Sanitaria Univ Friuli Cent, Cardiothorac Dept, Ple SM Misericordia 15, Udine, Italy
[2] Univ Bologna, S Orsola Univ Hosp, Div Cardiac Surg, IRCCS Bologna,ALMA Mater Studiorum, Bologna, Italy
[3] Univ Vita Salute San Raffaele, IRCCS San Raffaele Hosp, Div Cardiac Surg, Milan, Italy
[4] San Camillo Forlanini Hosp, Cardiothorac Dept, Rome, Italy
[5] Papa Giovanni XXII Hosp Bergamo, Cardiothorac Dept, Bergamo, Italy