Antioxidant protection system before and after coronary bypass surgery in coronary heart disease patients with left ventricular dysfunction

Abstract

The study involved 74 patients with coronary heart disease (CHD) (mean age 52,4±4,5 years), with stable effort and exertion angina, Stage II arterial hypertension (in 56% of the participants), and multifocal atherosclerosis in 61% of cases. Among CHD patients without substantial decrease in left ventricular contractility (ejection fraction, EF >45%), activity of antioxidant enzymes increased: for superoxide dismutase (SOD), katalase, and glutathione peroxidase - by 87,5%, 25%, and 34%, respectively. In patients with EF ≥ 35%, SOD and glutathione peroxidase activity increase is also observed (by 198% and 33%, respectively), as well as reduced katalase activity. In participants with EF<35%, pseudo-normalization of SOD activity and reduction of katalase and glutathione peroxidase activity was observed: antioxidant protection system (AOP) potential was decreased (initial, reversible phase). Reduced alpha-tocopherol level was registered only in individuals with EF<35%. Severe IF dysfunction (EF<28%) was associated with AOP activity decrease: by 67% for SOD, by 90% for katalase, and by 74% for glutathione peroxidase. Authors suggest that reduced AOP system reserve in patients with severely impaired LV contractility is one of the most important factors for complication risk, reperfusion (oxidative) and surgery stress.

Keywords

• coronary heart disease
• contractility
• antioxidant protection system
• lipid peroxidation