Hemostasis in Off-Pump Compared to On-Pump Coronary Artery Bypass Grafting: A Prospective, Randomized Study

Background We hypothesized that off-pump coronary artery bypass grafting has less impact on the hemostatic systems than on-pump surgery. Methods Thirty-one patients were randomized to on-pump or off-pump coronary artery bypass grafting. Factors of hemostasis as well as markers of endothelial activation were measured up to 24 hours after the operation: Fibrin D dimer, prothrombin fragment 1+2, α2-macroglobulin, protein C1 esterase inhibitor, fibronectin, and von Willebrand factor. Overall hemostasis potential, overall coagulation potential, and overall fibrinolysis potential were determined with a previously developed assay. We also measured platelet count before and after surgery. Results Fibrin D dimer and prothrombin fragment 1+2 concentrations were lower during surgery in the off-pump group (p< 0.001). Four hours after admission to the intensive care unit, these differences were eliminated. α2-macroglobulin, protein C1 esterase inhibitor, fibronectin, and von Willebrand factor concentrations did not differ between groups (p = 0.59, p = 0.28, p = 0.22, and p = 0.69). Protein C1 esterase inhibitor and von Willebrand factor concentrations increased over time (p< 0.001) in both groups. Overall hemostasis potential and overall coagulation potential increased over time (p< 0.001), while overall fibrinolysis potential decreased (p< 0.001) with no difference between groups (p = 0.69, p = 0.91). Platelet count decreased on the first postoperative day (p< 0.001), but increased from the first to the third postoperative day (p = 0.004) in both groups without any inter group difference (p = 0.82). Conclusions There was a tendency toward less activation of coagulation and fibrinolysis in low-risk patients during elective off-pump coronary artery bypass surgery when compared with on-pump surgery.