Objectives: To clarify the relationship between changes in redox balance and the development of new coronary lesions in patients with coronary artery disease (CAD).
Methods: We studied 82 CAD patients (70 males and 12 females, mean age 61.8 +/- 9.2 years) who underwent repeated coronary angiography within 1 year after percutaneous coronary intervention. Levels of serum lipid peroxide, erythrocyte glutathione peroxidase activity, and the redox state of erythrocyte (ratio of reduced to oxidized glutathione, the GSH/GSSG ratio) were measured at the time of follow-up coronary angiography. According to the development of significant stenotic lesions, we divided the patients into two groups: 57 patients without the development of new stenotic lesions (group A) and 25 patients showing new significant stenotic lesions within 1 year (group B).
Results: The serum lipid peroxide level in group B was significantly higher than those of group A (2.61 +/- 0.32 vs 1.74 +/- 0.16 nmol/ml, p < 0.01). Erythrocyte glutathione peroxidase activity did not differ significantly between two groups. The erythrocyte GSH/GSSG ratio in group B was significantly lower than that of group A (83 +/- 9.6 vs 126 +/- 7.3, p < 0.01). The sensitivity and specificity of GSH/GSSG ratio to detect CAD patients with the development of significant coronary stenosis were 80.0% and 61.4%, respectively.
Conclusions: CAD patients who showed development of new coronary lesions within 1 year have increased oxidative stress and imbalanced erythrocyte redox state. The GSH/GSSG ratio, an indicator for redox balance, could be a useful marker to identify high-risk CAD patients.