The prognostic value of soluble suppression of tumourigenicity 2 and galectin-3 for sinus rhythm maintenance after cardioversion due to persistent atrial fibrillation in patients with normal left ventricular systolic function

Aims Soluble suppression of tumourigenicity 2 (sST2) and galectin-3 are involved in cardiac fibrosis, inflammation, and remodelling. However, the place of sST2 and galectin-3 in predicting the outcomes of electrical cardioversion of atrial fibrillation (AF) is uncertain. We evaluated whether these biomarkers could predict sinus rhythm (SR) maintenance after cardioversion of persistent AF in patients with normal left ventricular systolic function. Methods and results The study included 80 patients with persistent AF, who underwent cardioversion from February 2016 to August 2018. The blood concentrations of sST-2 and galectin-3 were measured with ELISA and the ASPECT-PLUS assays. Clinical and electrocardiographic follow-up was performed at months 1, 6, and 12. Patients who maintained SR at 12 months had significantly lower concentrations of sST2, measured by ELISA and ASPECT-PLUS assays, than the remaining patients (16.9 +/- 9.8 vs. 28 +/- 22.9 ng/mL; P< 0.001; 28.7 +/- 13.4 vs. 40 +/- 25.1 ng/mL; P=0.003); the concentration of galectin-3 did not differ between these patients. Multivariable logistic regression showed that log-transformed sST2 ELISA was a significant predictor of SR maintenance at 12 months [odds ratio 0.14; 95% confidence interval (CI) 0.03-0.58; P= 0.006]. On receiver-operating characteristic curve analysis, the areas under the curve for the concentration of sST2 was 0.752 (95% CI 0.634-0.870; P < 0.001). The concentrations of sST2 measured with the two assays were strongly correlated (rho = 0.8; CI 95% 0.7-0.87; P= 0.001). Conclusion Soluble suppression of tumourigenicity 2, but not galectin-3, can be used to predict SR maintenance after cardio- version of AF in patients with normal left ventricular systolic function. The measurements of sST2 concentrations with the rapid lateral flow and enzyme-linked immunoassays were consistent.