The purpose of this study was to investigate the clinical outcome, inflammatory response and myocardial function in high-risk patients undergoing three different leukocyte depletion strategies. Over a four-month period, forty patients (EuroSCORE 6+) undergoing coronary revascularization were prospectively randomized to one of the four perfusion protocols: Group 1 (N=10): Conventional circuits (ECC) + two leukocyte filters (LG6B, Pall, USA) with the method of two-phase (continuous + strategic) leukofiltration; Group 2 (N=10): ECC + single leukocyte filter with the method of continuous leukofiltration; Group 3 (N=10): ECC + single leukocyte filter with the method of strategic leukofiltration; Group 4 (N=10) Control: ECC without leukocyte filt...