Miha Arnol1,2, Ivan Kneževič3,4. 1. Department of Nephrology, Centre for Kidney Transplantation, University Medical Centre Ljubljana, Ljubljana, Slovenia. 2. Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia. 3. Department of Cardiovascular Surgery, University Medical Centre Ljubljana, Ljubljana, Slovenia. 4. Transplantation Centre, University Medical Centre Ljubljana, Ljubljana, Slovenia.