Elevated Maresin‐1 Levels in Pericardial Fluid of Patients Undergoing Coronary Artery Bypass Grafting

BACKGROUND: Chronic inflammation plays a critical role in the pathophysiology of cardiovascular diseases. Specialized pro-resolving mediators derived from omega-3 fatty acids, such as Maresin-1 (MaR1), have been shown to promote inflammation resolution and exert cardioprotective effects. However, the clinical significance of MaR1 in coronary artery bypass grafting (CABG) patients remains unclear. AIMS: This study aimed to investigate MaR1 levels in plasma and pericardial fluid of patients undergoing elective coronary artery bypass grafting and to evaluate its potential as a biomarker of localized cardiac inflammatory resolution. METHODS: This cross-sectional analytic study included 50 patients undergoing elective CABG and 50 age- and sex-matched healthy controls. Plasma and pericardial fluid were collected from patients,and plasma from controls. MaR1 levels were quantified by ELISA. Group comparisons were performed using Kruskal-Wallis and Mann-Whitney U tests. Diagnostic performance was evaluated by receiver operating characteristic (ROC) analysis, and independent predictive value was assessed using multivariablelogistic regression. RESULTS: MaR1 levels were significantly higher in pericardial fluid (97.03 pg/mL) compared with patient plasma (61.02 pg/mL) and controls (42.45 pg/mL) (p < 0.001). ROC analysis demonstrated high discriminative performance (AUC = 0.975; sensitivity 93%, specificity 100%). Logistic regression confirmed MaR1 as an independent predictor of patient status after adjustment for age and sex (OR = 1.88, p < 0.001). CONCLUSION: The marked elevation of MaR1 in pericardial fluid reflects a localized resolution response in the cardiac microenvironment, underscoring its potential as a distinctive biomarker in cardiovascular disease. These findings suggest that MaR1 may serve as a novel biomarker reflecting localized cardiac inflammatory resolution in patients with coronary artery disease.