Is Beating Heart Coronary Artery Bypass Graft Surgery Associated with Lesser Oxidative Stress and Inflammatory Response?

Abstract

Cardiac operations using cardiopulmonary bypass have been associated with systemic inflammatory response, increased levels of circulating adhesion molecules, and oxidative stress. This study aims to assess various responses in patients undergoing coronary artery bypass grafting (CABG) with or without Cardiopulmonary bypass (CPB) with respect to time after surgery. Sixty consecutive patients undergoing CABG either by on-pump or off-pump technique were studied. Serum levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), high-sensitivity C-Reactive Protein (hs-CRP), soluble vascular cell adhesion molecule (sVCAM), glutathione(GSH), vitamin C, super oxide dismutase(SOD), and malondialdehyde (MDA) were measured. The parameters showed devoted inflammatory response, oxidative stress, and endothelial activation at 24 and 48 h postoperatively in on-pump and off-pump CABG surgery. IL-6 and hs-CRP showed significant elevation at 24 h after surgery and they were quite pronounced in on-pump cases compared to in off-pump cases. The oxidative stress is produced in both types of surgery, more so in the on-pump cases. The levels of endogenous antioxidants started rising immediately as observed in 48 h values, but not Vitamin C. Mean serum levels of sVCAM-1 also increased significantly after surgery in both the groups. The CABG procedure resulted in increased sera levels of sVCAM implying the increased endothelial activation in both the groups. CABG procedure results in inflammatory response and oxidative stress after both on and off-pump methods, but off-pump CABG causes lesser oxidative stress and cytokine response than the on-pump arrested heart technique.