sST2: a novel predictor of mortality risk in acute heart failure with reduced ejection fraction?

Novel biomarkers are emerging in heart failure (HF), although their prognostic value is not yet fully established. Our objective was to assess the prognostic value of selected biomarkers, particularly soluble suppression of tumourigenicity-2 (sST2), with respect to mortality in patients admitted with acute heart failure with reduced ejection fraction (HFrEF).

To evaluate the association between sST2 and all-cause mortality in patients hospitalised for acute HFrEF, and to compare its prognostic performance with that of NT-proBNP.

We conducted a prospective, single-centre study including 104 patients with acute HFrEF. Serum and plasma samples were obtained at admission. Several biomarkers were analysed, including sST2, a member of the interleukin-1 receptor family expressed in response to cellular injury. Univariate Cox regression was used to identify biomarkers associated with mortality. For those with statistically significant associations, diagnostic accuracy analyses were performed to estimate the area under the curve (AUC) and prospective cut-off values for mortality prediction.

A total of 104 patients were included (78% male; mean age 66.7 years). The mean left ventricular ejection fraction was 21%. At the end of follow-up, 90% were receiving beta-blockers, 87% ACE inhibitors/angiotensin-receptor blockers/angiotensin-receptor–neprilysin inhibitors, 74% mineralocorticoid receptor antagonists, and 72% sodium–glucose cotransporter-2 inhibitors (Table 1). Over a median follow-up of 23.5 months, 20 deaths occurred. sST2 was significantly associated with mortality (HR 1.22, 95% CI 1.11–1.35) with an AUC of 0.73, higher than that of NT-proBNP (0.66). Using a cut-off of 99.7 ng/mL, sensitivity was 25% and specificity 96.4%. With a prevalence of 19.2%, the negative predictive value was 84.4% and the positive predictive value 62.5%. The receiver operating characteristic curves for NT-proBNP and sST2 are shown in the Figure.

sST2 demonstrated acceptable prognostic value for all-cause mortality following hospitalisation for acute HFrEF, outperforming NT-proBNP in this cohort. Larger studies are required to validate these findings and to further define the role of sST2 across different patient subgroups.For image description, please refer to the figure legend and surrounding text.

Figure1. Predictive capacity for mortality