The role of tenascin-C and oxidative stress in rheumatic and congenital heart valve diseases: an observational study.

Objective: The aim of this study was to evaluate the association of tenascin-C (TnC) and total oxidant-antioxidant status to rheumatic or congenital heart valve diseases (HVD) in pediatric patients.

Methods: Fifty pediatric patients (25 rheumatic HVD patients and 25 congenital HVD patients) and 20 healthy age-matched control subjects, aged 3-17 years, were enrolled in this observational and cross-sectional study. Serum total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI) and TnC levels were compared among the groups. ANOVA and Kruskal-Wallis tests were used for statistical analysis.

Results: Serum TnC level of the patients with rheumatic HVD [median 9.09 (0.94-46.30) ng/mL] was significantly higher than both congenital HVD and control groups [median 2.97 (0.66-11.80) ng/mL; p<0.01, 4.72±1.77 ng/mL; p<0.05, respectively]. However, there was no statistically significant difference between the congenital and control groups in terms of serum TnC level. The levels of serum TAC, TOS and OSI were found to be statistically similar in all groups. In addition, there were no correlations between the level of TnC, and TOS and OSI.

Conclusion: Tenascin-C can be used as a biochemical marker in the differential diagnosis of rheumatic and congenital HVD. As the oxidant and antioxidant systems were found to be in equilibrium in rheumatic and congenital HVD, oxidative stress can be thought not to have a marked role in the etiopathogenesis of rheumatic HVD during childhood.