Production of Reactive Oxygen Species and Antioxidant Defense Systems in Patients after Coronary Artery Bypass Grafting: One-Week Follow-up Study

Journal of Clinical and Basic Cardiology 2005; 8 (1-4): 33-36

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Keywords: Bypass,  Chirurgie,  Graft,  Kardiologie,  Studie,  Bypass,  cardiac surgery,  cardiology,  coronary artery bypass grafting,  study

Objectives: Great cardiac surgery performed with cardiopulmonary bypass is associated with systemic inflammatory response which is characterised by an extensive overproduction of reactive oxygen species, too. This oxidative stress draws off the endogenous stores of antioxidant systems and usually evokes a decrease of antioxidant status of the organism. According to the recent observations, the new off-pump method is less harmful and evokes only moderate systemic inflammatory reaction. Aim of study: Follow-up of patients with low and high left ventricular ejection fraction undergoing on-pump or off-pump cardiac surgery (coronary artery bypass grafting) in course of the first postoperative week. Patients and methods: Forty-one patients were divided in four groups according to their left ventricular function (patients with low or high left ventricular ejection fraction) and to the surgical technique used (with or without cardiopulmonary bypass). Immediately before surgery and in course of the first postoperative week, samples of central venous line were drawn and some parameters of oxidative metabolism were analysed: plasma levels of total antioxidant status (TAS) and thiobarbituric acid reactive substances (TBARS) as well as the erythrocyte activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx). Results: Patients undergoing surgical myocardial revascularisation - regardless of the grade of their cardiac dysfunction or of the kind of surgical technique used – revealed a marked decrease of TAS even at the preoperative period that did not change substantially during the early postoperative period. In the group of patients with high left ventricular ejection fraction a tendency to further decrease of plasma levels of TAS was observed. Despite of negligible changes of the plasma levels of TBARS, during the short postoperative period markedly decreased activities of SOD and only non-significantly increased activities of GPx were demonstrated in the whole cohort of investigated patients. Conclusions: Patients with coronary artery disease undergoing surgical revascularisation (coronary artery bypass grafting) revealed a marked decrease of antioxidant capacity before and after surgical event. The extensive treatment of these patients with antioxidant drugs and vitamins was recommended even in the preoperative period.