Biochemical and hemodynamic effects of ascorbic acid and alpha-tocopherol in coronary artery surgery

Abstract

This study was undertaken to evaluate the effects of alpha-tocopherol and ascorbic acid on markers of myocardial reperfusion injury and myocardial contractile function after coronary artery surgery. Forty-eight patients were divided into 4 groups; 300 mg/day alpha-tocopherol was given orally to the patients in group I for 14 days. In groups II and III, 4g of ascorbic acid was administered intravenously prior to induction and in the cardioplegic solution, respectively. Group IV was the control group. Blood samples were taken to determine the concentrations of creatine phosphokinase MB isoenzyme, malondialdehyde, uric acid, ascorbic acid and alpha-tocopherol in the perioperative period. Left ventricular functions were determined by means of MUGA scans and echocardiography preoperatively and on the 3rd and 7th days, postoperatively. The changes in serum creatine phosphokinase MB and malondialdehyde were significantly lower in study groups, when compared with the control group. We observed no significant changes in ventricular function, requirement for (+) inotropic agents and the incidence of ventricular arrhythmias among the groups, postoperatively. Biochemical findings are consistent with the free radical hypothesis. But we could not confirm these data with hemodynamic findings. This is probably due to the population of low-risk elective coronary surgery patients in this study.