Human cytokine responses to coronary artery bypass grafting with and without cardiopulmonary bypass

Background. Coronary artery bypass grafting (CABG) is associated with a sys temic inflammatory response. This has been attributed to cytokine release c aused by extracorporeal circulation and myocardial ischemia. This study com pares the inflammatory response after CABG with cardiopulmonary bypass and after minimally invasive direct coronary artery bypass grafting (MIDCABG) w ithout cardiopulmonary bypass. Methods. Cytokine release and complement activation (interleukin-6 and inte rleukin-8, soluble tumor necrosis factor receptors 1 and 2, complement fact or C3a, and CI esterase inhibitor) were determined in 24 patients before an d after CABG or MIDCABG. The maximum body temperature, chest drainage, and fluid balance were recorded for 24 hours after operation. Results. Release of interleukin-6, interleukin-8, and tumor necrosis factor receptors 1 and 2 was significantly higher (p less than or equal to 0.005) in the CABG group than the MIDCABG group just after operation, After 24 ho urs, a significant increase in interleukin-6 was also found in the MIDCABG group (p = 0.001) compared with preoperative value. Body temperature and fl uid balance were significantly higher after CABG (p less than or equal to 0 .001). Conclusions. Minimally invasive direct coronary artery bypass grafting repr esents a less traumatizing technique of surgical revascularization. The red uction in the inflammatory response may be advantageous for patients with a high degree of comorbidity. (C) 1999 by The Society of Thoracic Surgeons.