Redox Imbalance and Coronary Complexity Linking Oxidative Stress Biomarkers to SYNTAX II Score in Acute Coronary Syndrome.

Background: Lipoprotein metabolism, inflammation, and oxidative stress (OS) play interconnected roles in the pathogenesis of acute coronary syndrome (ACS). However, the relationship between oxidative stress biomarkers and coronary artery disease (CAD) complexity, particularly as assessed by the SYNTAX II score, remains incompletely understood. This study aimed to evaluate serum levels of oxidative stress-related biomarkers and to investigate their association with the SYNTAX II score in patients with newly diagnosed ACS. Methods: This was a retrospective, single-center observational study. A total of 60 patients with newly diagnosed ACS who underwent percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) were consecutively enrolled. Serum levels of superoxide dismutase (SOD), advanced oxidation protein products (AOPP), glutathione, catalase, and malondialdehyde (MDA) were measured using ELISA methods. Associations between oxidative stress markers and the SYNTAX II score were analyzed using correlation and regression analyses. Results: Median levels of SOD, AOPP, and glutathione were 261.0 (244.18-324.86) U/L, 23.81 (22.62-25.80) ng/mL, and 6.08 (5.28-11.46) ng/mL, respectively. Mean catalase and MDA levels were 339.07 ± 44.81 pg/mL and 0.66 ± 0.07 mmol/L. The SYNTAX II score was positively correlated with SOD, AOPP, glutathione, catalase, and MDA, as well as with age, female sex, and potassium levels, while it was negatively correlated with hemoglobin, creatinine clearance, and left ventricular ejection fraction (all p < 0.05). Patients with higher SYNTAX II scores demonstrated elevated levels of both oxidant and antioxidant biomarkers. Conclusions: Oxidative stress-related biomarkers were associated with the SYNTAX II score in patients with newly diagnosed ACS.