Abstract: To explore the effects of coronary artery bypass graft(CABG) surgery performed by using both standard cardiopulmonary bypass (CPB) or the octopus technique on Endothelin-1(ET-1) levels and left ventricular function. MethodsSixty-two patients undergoing CABG surgeries were randomly divided into two groups: the G1 group (n=30) which received CPB-CABG and the G2 group(n=32) which received off-pump CABG (OPCABG). Blood samples were obtained before anesthesia (T1), before operation (T2), 6h(T3) and 24h(T4) after the end of operation. Serum Endothelin-1, CI and LVSWI were determined at each time-point. ResultsSerum ET-1 of the G1 group was significantly increased at T3 and T4 time-points and of the G2 group was decreased at T2 timepoint and increased at T4 timepoint. Serum ET-1 of the G2 group was decreased at T3 and T4 time-points compared with the G1 group (P<0.05). Compared with T1 time-point, CI of the G1 group at T2 and T3 time-points and that of the G2 group at T2 time-point were markedly decreased (P<0.05), and also LVSWI of the G1 group at the T3 and T4 timepoints were markedly decreased (P<0.05). Compared with the G1 group, CI and LVSWI of the G2 group at the T3 time-point were increased (P<0.05). Conclusion Off-pump CABG can decrease the output of ET-1 and has a protective effect on myocardial injury and it is superior to CPB-CABG.

Key words: Endothelin-1, Left heart function, Cardiopulmanory bypass, Coronary artery bypass grafting