Reduced expression of systemic proinflammatory cytokines after off-pump versus conventional coronary artery bypass grafting

Background: Both cardiopulmonary bypass (CPB) and operative trauma are asso ciated with increased expression of proinflammatory cytokines. We assessed the relative contribution of CPB on activation of various proinflammatory c ytokines in patients undergoing coronary revascularization by comparing the m with patients receiving coronary artery bypass grafts using off-pump (OPC AB) techniques. Methods: Twenty-six patients were assigned to either the OP CAB procedure using a suction device and regular sternotomy (n = 13) or wer e treated conventionally using extracorporeal circulation, blood cardiopleg ia and hypothermic arrest (29-31 degreesC; n = 13). C-reactive protein and systemic levels of TNF-alpha, TNF specific receptors Rp1 and Rp2, Interleuk in-6 (IL-6) and soluble IL-2 receptors (sIL-2r) were assayed by ELISA or EI A. To account for systemic nitric oxide production, total nitrate/nitrite ( NOx) was measured using the Griess reaction. Results: Coronary revasculariz ation with CPB was associated with a significant expression increase in the TNF-system and sIL-2r when compared to the OPCAB patients. Although IL-6 e xpression did not differ between both groups, C-reactive protein levels wer e significantly lower in the OPCAB group. Moreover, systemic NOx levels as the stable end-product of nitric oxide were lower in the OPCAB group. Concl usions: The data of the present study indicate that, despite comparable sur gical trauma, the OPCAB revascularization procedure without the use of CPB and cardioplegic arrest significantly reduces the systemic inflammatory res ponse syndrome and early catecholamine requirement. This may contribute to improved organ function, subsequently resulting in improved postoperative r ecovery from surgical revascularization procedures, particularly in critica lly ill patients.