Prognostic value of soluble ST2 in adults with congenital heart disease

Soluble suppression of tumourigenicity-2 (sST2) is upregulated as response to myocardial stress and may be a potential biomarker for risk stratification in patients with adult congenital heart disease (ACHD). This study aimed to investigate the release of sST2 and its association with cardiovascular events in ACHD.

In this prospective cohort study, 602 consecutive patients with ACHD visiting the outpatient clinic were included (2011-2013). The association between sST2 and a primary composite endpoint of all-cause mortality, heart failure, hospitalisation, arrhythmia, thromboembolic events or cardiac interventions was investigated using multivariable Cox regression.

sST2 was measured in 590 (98%) patients (median age 33 [25-41] years, 42% women). After a median follow-up of 5.8 [IQR 5.1-6.2) years, 225 (38.5%) reached the primary endpoint. sST2 was significantly associated with the primary endpoint when adjusted for age, sex, creatinine and N  terminal pro-B type brain natriuretic peptide (NT-proBNP) (HR per twofold higher sST2: 1.28, 95% CI 1.03 to 1.58, p=0.025). This association negated when adjusted for clinical variables and NT-proBNP (HR per twofold higher sST2: 1.19, 95% CI 0.96 to 1.48, p=0.106). Stratified analysis in complex ACHD did show a significant association between sST2 and the primary endpoint when adjusted for clinical variables and NT-proBNP (HR per twofold higher sST2: 1.31, 95% CI 1.01 to 1.69, p=0.043). Sex-specific analysis showed an association between sST2 and the primary endpoint in women (HR per twofold higher sST2 1.80, 95% CI 1.30 to 2.49, p<0.001) but not in men (HR per twofold higher sST2 1.19, 95% CI 0.90 to 1.56, p=0.223).

sST2 is a promising novel biomarker in patients with ACHD, specifically in complex ACHD and women. Future research is warranted to elucidate sex-specific and diagnosis-specific differences.