Release of S100B during coronary artery bypass grafting is reduced by off-pump surgery

Background. S100B, a plasma marker of brain injury, was compared after coro nary artery bypass grafting with and without cardiopulmonary bypass (CPB). Methods. Fourteen patients with off-pump operations and 18 patients with CP B were compared. Seven patients in the oft-pump group underwent a minithora cotomy and received only an arterial graft, whereas 7 patients underwent st ernotomy and received both an arterial and one or two vein grafts. S100B wa s measured in arterial plasma using an immunoassay with enhanced sensitivit y. Results. S100B before the operation was 0.03 mu g/L. At wound closure, S100 B in patients of the off-pump and CPB groups reached a maximum level of 0.2 2 +/- 0.07 and 2.4 +/- 1.5 mu g/L, respectively (p < 0.001). No strokes occ urred. patients without CFB receiving arterial and vein grafts released sli ghtly more S100B (p < 0.05) than patients with only arterial grafting. In p atients undergoing CPB, S100B increased slightly before aortic cannulation (p < 0.001), to the same level as the maximum reached for the non-CPB group . Conclusions. Coronary artery bypass grafting with CPB caused a 10-fold grea ter increase in S100B than off-pump grafting. S100B release after oft-pump sternotomy with vein grafting was slightly greater than in arterial graftin g through a minithoracotomy. (C) 1999 by The Society of Thoracic Surgeons.