[1] Natl & Kapodistrian Univ Athens, Sch Med, Evaggelismos Gen Hosp, Clin Ergospirometry Exercise & Rehabil Lab, 45-47 Ypsilantou Str, Athens 10676, Greece
[2] Natl & Kapodistrian Univ Athens, Cardiac Surg Intens Care Unit, Onassis Cardiac Surg Ctr, Athens, Greece
[3] Natl & Kapodistrian Univ Athens, Dept Internal Med 2, Propaedeut & Diabet Ctr, Univ Gen Hosp Attikon,Med Sch, Athens, Greece
[4] Natl & Kapodistrian Univ Athens, Immunol & Histocompatibil Dept, Evaggelismos Gen Hosp, Athens, Greece
[5] Natl & Kapodistrian Univ Athens, Heart Failure Unit, Dept Clin Therapeut, Alexandra Hosp, Athens, Greece
[6] Natl & Kapodistrian Univ Athens, Aretaieion Hosp, Sch Med, Hematol Lab Blood Bank, Athens, Greece