Comparison of Serum Myocardial Biomarkers Following Two Different Methods of Venoaortic Connection in Coronary Artery Bypass Grafting: A Randomized Clinical Trial

Background: Myocardium will expose to excessive ischemia and reperfusion during post-cardiac surgery, hence the aim of this study was to investigate the cardioprotective effect of sequential partial aortic side biting technique for proximal veno-aortic anastomosis constructions in patients undergoing coronary artery bypass grafting (CABG). Methods: In this randomized clinical trial study, 60 consecutive patients who were diagnosed to suffering from triple vessel coronary artery diseases were selected. CABG patients were assigned randomly into two groups; the first group received sooner and gradual myocardial reperfusion one-by-one top end venous anastomosis to the aorta (sequential aortic side biting technique) (n = 30) and the second group undergo proximal anastomoses constructed during a single period of aortic side biting (single aortic side biting technique) (n = 30). The serum levels of myocardial damage biomarkers including creatine phosphokinase-MB (CPK-MB), Troponin I, glutathione peroxidase (GPX), superoxide dismutase (SOD), malondialdehyde (MDA) and catalase (CAT) were measured preoperatively, postoperatively and 24 h after operation. Independent t- tests was used to compare results between groups. Results: The level of all myocardial biomarkers increased after the operation. Those in study group had significantly lower levels of troponin I (P < 0.001), CPK-MB (P = 0.001), GPX (P = 0.007), SOD (P = 0.005), and CAT (P = 0.015), 24h after the operation when compared to control group. Only the serum level of CPK-MB was significantly lower in study group after the operation (P = 0.029) while the other markers were comparable. Conclusions: Sequential partial occluding aortic side biting technique associated with less myocardial damage and ischemia-reperfusion injury compared to conventional single method in patients undergoing elective coronary grafting.