Off-pump coronary artery bypass surgery versus standard linear or pulsatile cardiopulmonary bypass: endothelial activation and inflammatory response

Abstract

Objective: Poor outcomes after coronary artery bypass grafting (CABG) have been linked to perioperative endothelial activation and systemic inflammatory responses. The use of pulsatile cardiopulmonary bypass (PCPB) or off-pump CABG (OPCABG) may minimise these phenomena. We compared biochemical and clinical outcomes among patients who underwent CABG with PCPB, CABG with linear CPB (LCPB) or OPCABG.

Methods: Sixty consecutive patients undergoing isolated elective CABG were prospectively randomised trial to receive pulsatile CPB (group A, 20 patients), linear CPB (group B, 20 patients) or OPCABG (group C, 20 patients). Levels of proinflammatory cytokines (interleukins-2, -6, and -8), anti-inflammatory cytokines (interleukin-10) and endothelial markers (vascular endothelial growth factor (VEGF), monocyte chemo-attractant protein (MCP)-1) were measured before, during and after surgery.

Results: VEGF and MCP-1 levels increased significantly during surgery in all groups, but they increased the least and were the lowest overall with OPCABG. They rose most and peaked overall with LCPB. Interleukin-2 levels remained stable during OPCABG but decreased equally during PCPB and LCPB. Interleukin-6 and -8 levels rose significantly during both types of CPB versus OPCABG. Interleukin-10 levels increased significantly in all groups during surgery, but they rose least and were the lowest overall with OPCABG and rose most and were the highest overall with PCPB. Intubation times, intensive care unit (ICU) stay and hospital stay were significantly longer in the LCPB group than the other two groups.

Conclusions: LCPB appears to promote endothelial activation and cytokine secretion, which may delay recovery. OPCABG was associated with slight endothelial activation and cytokine response. PCPB significantly attenuates endothelial/cytokine leakage, resulting in hospital outcomes comparable with those after OPCABG.