Objective: We aimed to assess the role of oxidative stress (OS) and inflammation in the early evaluation of initial acute non -ST -elevation myocardial infarction (NSTEMI) compared with unstable angina pectoris (USAP).

Materials and Methods: Forty-seven (54%) patients with NSTEMI and 40 (46%) with (USAP) were included in this cross-section observational study. We assessed the oxidative stress and inflammation parameters. Statistical analysis was performed using Fisher’s exact test, Chi-square test, Mann-Whitney U test, Student’s t-test, and Pearson correlation analysis for assess the correlations between variables.

Results: Plasma total oxidative stress (TOS) and OS index levels were significantly higher (p<0.001 for both comparisons), in patients with NSTEMI. In addition, white blood cell count (WBC) and high-sensitive C-reactive protein (hs-CRP) levels were significantly higher in patients with NSTEMI (respectively; p<0.001, p=0.02). Age, WBC and low- density lipoprotein cholesterol showed positive correlations with TOS level (Pearson correlation coefficient: r=0.290, p=0.006; r=0.431, p<0.001; r=0.219, p=0.042 respectively), and also age showed positive correlation with OS index (Pearson correlation coefficient; r=0.246; p=0.021). However, the values of the troponin I and creatine kinase-MB fraction did not differ between the two groups (p>0.05 for all).

Conclusion: TOS, OSI, WBC and CRP levels are significantly higher in NSTEMI subject. These data suggest that inflammatory processes and oxidative stress together play a role in the pathogenesis of acute NSTEMI.