Inflammatory and Hemostatic Activation in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting

Abstract

To characterize hemostatic differences imposed by 2 common cardiac surgeries, the authors studied patients undergoing coronary artery revascularization by off-pump (n = 13) or cardiopulmonary bypass on-pump (n = 26) technique. Blood samples collected to 4 days post-surgery were evaluated by flow cytometry and enzyme-linked immunosorbent assay. A significant inflammatory response occurred in both the groups after surgery shown by increased interleukin cytokines and C-reactive protein; however, levels peaked lower and hours later in the off-pump group. Platelets (P-selectin; platelet-leukocyte complexes) and leukocytes (CD11b) were activated only in on-pump patients. Thrombin generation was enhanced in both groups after surgery. Only in the on-pump patients, the thrombin-antithrombin complex, pro-thrombin fragment 1.2, and thrombomodulin (vascular integrity) decreased intraoperatively. Tissue plasminogen activator and plasminogen activator inhibitor-1 were greater in the on-pump patients. Off-pump surgery may place patients at higher risk of postoperative hypercoagulability because of normal platelet function, intraoperative thrombin generation, less fibrinolytic activity, and lack of vascular protection.