Introduction and objectives: The novel biomarker ST2 provides diagnostic information in a variety of clinical settings. The objective was to determine whether measurement of the soluble ST2 (sST2) concentration improves risk stratification in outpatients with decompensated heart failure (HF).
Methods: The concentrations of sST2 and N-terminal probrain natriuretic peptide (NT-proBNP) and a heart failure severity score (HFSS), based on Framingham criteria, were determined at baseline and 2 weeks later in 48 outpatients with decompensated hf. The ratio of the value of each variable at week 2 relative to baseline was determined. Patients were followed for 1 year and cardiac events (i.e. death, HF admission and heart transplantation) were recorded.
Results: By 1 year, 56% of patients had experienced a cardiac event. The sST2 ratio was significantly lower in patients who did not have a cardiac event (0.6 ± 0.39 vs. 1.39 ± 0.92; P< .001). After multivariable adjustment, the sST2 ratio remained an independent predictor of risk (odds ratio=1.054; 95% confidence interval, 1.01-1.09; P=.017). The optimum cut-point for the sST2 ratio determined by receiver operating curve [ROC] analysis was 0.75; this accounted for 25% of the change in sST2 by week 2. Among patients with an sST2 ratio >0.75 and a baseline NT-proBNP level >1000 ng/L, 72% had a cardiac event (P=.018), while no events occurred in patients with marker values below these reference levels.
Conclusions: Determination of the sST2 concentration in serial samples provided additional risk stratification in outpatients with decompensated HF. Repeated measurement of sST2 may aid clinical decision-making.