Correlation between Syndecan-1 in Inter Category of RACHS-1 Score and Immediate Clinical OutcomesOA

Background:Low cardiac output syndrome(LCOS)is a frequent and serious complication after pediatric cardiac surgery.Endothelial glycocalyx(EG)degradation,indicated by elevated syndecan-1,contributes to microvascular dysfunction and postoperative instability.The relationship between syndecan-1 dynamics and surgical risk categories remains unclear.Objective:To examine the association between perioperative syndecan-1 levels and clinical outcomes across Risk Adjustment for Congenital Heart Surgery(RACHS-1)categories.Methods:We analyzed 106 children(RACHS-1 categories 2–4)undergoing elective cardiac surgery with cardiopulmonary bypass(CPB).Syndecan-1 was measured at baseline(T0),4 h(T4),and 72 h(T72).Outcomes included LCOS,vasoactive inotropic score(VIS),Pediatric Logistic Organ Dysfunction(PELOD-2),pediatric intensive care unit(PICU)stay,and mortality.Analyses used Kruskal–Wallis,Bonferroni post hoc tests,Spearman correlation,and multivariable regression adjusted for CPB duration,cross-clamp time,and pre-PICU status.Results:Syndecan-1 differed significantly across RACHS groups at T0(p=0.044)and T72(p=0.015).RACHS score was weakly correlated but significant with syndecan-1 at T72(r=0.238,p=0.019)and decline from T4–T72(r=0.249,p=0.013),indicating delayed recovery at higher risk.RACHS-4 patients had the highest VIS and PELOD-2 scores and longer PICU stay.In adjusted models,RACHS-3 was associated with higher syndecan-1 at T72(β=+51.9,p=0.016),higher VIS 0–4 h(β=+4.9,p=0.008),and increased LCOS risk(OR 5.99,95%CI 1.61–25.70,p=0.010).RACHS-4 showed greater organ dysfunction but LCOS risk was attenuated(OR 0.19 vs.RACHS-3,p=0.035).Mortality was highest in RACHS-4(17.6%)but not statistically significant(p=0.368).Conclusion:Higher RACHS categories are linked with delayed EG recovery,greater vasoactive support,and more severe organ dysfunction.Syndecan-1 kinetics at 72 h,alongside VIS and LCOS,may serve as adjunctive markers for postoperative risk stratification in pediatric cardiac surgery.