['Leucocyte filtration can reduce inflammation and end-organ damage. The aim of this study was to test the cardioprotective effect of systemic leucocyte filtration during cardiopulmonary bypass (CPB) for coronary revascularization.', 'Sixty patients scheduled for elective coronary artery bypass grafting were prospectively randomised to receive either a test leucocyte-depleting (LD) filter or a control standard arterial line filter in the CPB circuit. Myocardial injury was determined by serum Troponin T concentration up to 72 h postoperatively. In addition, perioperative neutrophil counts, serum elastase and electrocardio-grams (ECGs) were evaluated.', 'There was a peak of Troponin T release at 6 h in both groups. There was no difference between LD or control group Troponin T at any time point. No difference in neutrophil count was found. A greater rise in neutrophil elastase occurred in the LD group during CPB and 10 min post CPB (376 and 496 versus 108 and 228 mcg/L, p<0.001).'] Does leucocyte-depleting arterial line filtration reduce myocardial injury assessed by Troponin T during routine coronary artery bypass grafting using crossclamp fibrillation?