Prognostic value of serum myeloperoxidase in diabetic patients undergoing elective percutaneous coronary intervention

Abstract Diabetes mellitus (DM) increases the risk of cardiovascular disease (CVD) through mechanisms involving chronic inflammation and oxidative stress. Myeloperoxidase (MPO), a heme-containing enzyme catalyses the formation of reactive oxygen species (ROS). This study investigated the prognostic value of serum MPO in diabetic patients with chronic coronary artery disease (CAD) undergoing elective percutaneous coronary intervention (PCI). Patients with stable CAD were enrolled (100 with T2DM; 100 controls). Serum MPO activity was measured at baseline and follow-up (6–15 months post-PCI). Major adverse cardiac and cerebrovascular events (MACCE) were assessed. MPO-mediated lipid oxidation was examined by quantification of oxidized phosphatidylcholines (OxPCs), and functional effects were assessed using viability and tube formation assays. Follow-up MPO levels showed a positive correlation with SYNTAX score and were significantly higher in patients who experienced MACCE compared with those who did not [71% difference] ( p < 0.001 for both). A serum MPO threshold of > 203.49 ng/mL was predictive of adverse cardiovascular outcomes. In vitro experiments showed that MPO treatment increased generation of multiple OxPC species in a concentration-dependent manner and reduced cell viability and impaired angiogenic capacity ( p < 0.01). These findings highlight MPO as a potential contributor and prognostic biomarker of adverse cardiovascular outcomes in diabetic patients undergoing PCI.