Objective  This study aims to investigate the relationship of serum myeloperoxidase (MPO) and blood lipid levels with the severity of coronary artery lesions and major adverse cardiovascular event (MACE) in patients with acute coronary syndrome (ACS).

Methods  From May 2023 to January 2025, 216 ACS patients admitted to Yanbian University Hospital were enrolled as the study subjects. According to the disease types, they were divided into unstable angina pectoris (UAP group, n = 69), ST elevation myocardial infarction (STEMI group, n = 101), and non-ST elevation myocardial infarction (NSTEMI group, n = 46) groups. Additionally, 94 patients with other diseases were selected as controls (control group, n = 94). The serum MPO and blood lipid levels of the four groups were compared, and their relationships with the severity of coronary artery lesions in ACS patients were analyzed. ACS patients were further divided into MACE and non-MACE groups based on whether MACE occurred, and their serum MPO and blood lipid levels were compared. The receiver operating characteristic (ROC) curves were plotted to analyze the predictive value of serum MPO and blood lipid levels for MACE.

Results There were statistically significant differences in total cholesterol (CHO), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), and MPO levels among the four groups (P < 0.05). The STEMI group had the highest CHO level, which was (4.70 ± 1.30) mmol/L. The NSTEMI group had the lowest HDL-C level, which was (0.92 ± 0.32) mmol/L. LDL-C and MPO levels in the NSTEMI group were the highest, which were (3.04 ± 1.38) mmol/L and (175.90 ± 14.59) ng/mL (P < 0.05). With the increase of coronary artery lesion severity in ACS patients, LDL-C and MPO levels showed an increasing trend (P < 0.05). LDL-C levels in patients with mild, moderate, and severe coronary artery lesions were (2.51 ± 0.91) mmol/L, (3.08 ± 1.37) mmol/L, and (2.78 ± 0.92) mmol/L, respectively. MPO levels were (109.65 ± 16.02) ng/mL, (180.79 ± 22.47) ng/mL, and (150.89 ± 21.32) ng/mL, respectively. The Gensini score of ACS patients was positively correlated with MPO (r = 0.148, P < 0.05). Serum MPO was positively correlated with CHO and LDL-C (r = 0.277 and 0.356, P < 0.05), and negatively correlated with HDL-C (r = －0.186, P < 0.05). The HDL-C level in the MACE group (0.49 ± 0.21 mmol/L) was lower than that in the non-MACE group (1.04 ± 0.29 mmol/L). The levels of CHO, LDL-C, and MPO (6.20 ± 1.27 mmol/L, 5.23 ± 0.70 mmol/L, and 400.52 ± 84.41 ng/mL) were higher than those in the non-MACE group (4.35 ± 1.21 mmol/L, 2.66 ± 0.94 mmol/L, and 133.67 ± 87.31 ng/mL) (P < 0.05). The area under the curve for the combined prediction of MACE in patients with ACS using CHO, HDL-C, LDL-C, and serum MPO was 0.893 (95% CI, 0.850-0.936), which was higher than that of each indicator (0.703 95% CI, 0.634-0.773, 0.788 95% CI, 0.729-0.847, 0.800 95% CI, 0.736-0.864, and 0.805 95% CI, 0.747-0.862).

Conclusion MPO and blood lipids are closely associated with the severity of coronary artery lesions and MACE in patients with ACS. Their combined use demonstrates high predictive value for MACE and is valuable for clinical application and promotion.