Reduction of blood coagulation and monocyte-platelet interaction following the use of a minimal extracorporeal circulation system (Synergy) in coronary artery bypass grafting (CABG)

Cardiovascular surgery with cardiopulmonary bypass (CPB) induces activation of blood coagulation and systemic inflammation involved in post-operative complications. Our study evaluated the impact of the minimal extracorporeal circulation (mini-CPB) system (Synergy®, Sorin Group) on these functional aspects. Twenty patients were randomly assigned to standard CPB (n=10) or to Synergy (n=10). Platelet expression of PAC-1, and monocyte/granulocyte-platelet conjugates were evaluated by flow cytometry. A leukocyte-platelet adhesion index was calculated after cell number normalization. ELISAs were performed to measure IL-6 and TNF-a, thrombinantithrombin III complexes (TAT), prothrombin fragments (F1+2), ß-thromboglobulin (ß-TG) and sP-selectin (sCD62P). Blood samples were drawn at the time of anesthesia (T1), at the end of CPB (T2), and at 4 (T3) and 24 hours (T4) after weaning from CPB. All patients were similar for clinical characteristics. When compared to standard CPB, the Synergy showed lower levels of the monocyte-platelet adhesion index at T2 (0.023 ± 0.005 vs 0.063 ± 0.013, P = 0.0092) and T4 (0.031 ± 0.003 vs 0.055 ± 0.005, P = 0.0017), TAT complexes at T2 (27.175 ± 5.967 vs 86.592 ± 5.415, P = 0.0005) and T3 (26.977 ± 2.468 vs 45.146 ± 4.365, P = 0.0041), F1+2 fragments at T2 (2.222 ± 0.226 vs 4.249 ± 0.292, P = 0.0009), and sP-selectin at T3 (115.17 ± 19.623 vs 169.554 ± 19.709, P = 0.0703) and T4 (108.542 ± 6.429 vs 140.799 ± 14.771, P = 0.0833). In summary,the Synergy exhibited a lower post-operative activationof blood coagulation, together with a reduced interaction between circulating monocytes and platelets.