ST2 elevation in heart failure, predictive of a high early mortality

Abstract

Background: Soluble suppression of tumorigenicity-2 (sST2) is a novel biomarker shown to be useful for prognostic assessment in heart failure (HF). However, very limited data exists about its prognostic utility in patients with HF in India. Methods: We studied 150 patients [mean age 67.7 ± 13.3, 93 (62%) males], hospitalized with clinical HF, irrespective of their left ventricular ejection fraction (LVEF). HF was confirmed by N-terminal probrain natriuretic peptide (NT-proBNP) value above 125 ng/L. Primary end point was death or cardiac transplant at 1-year follow-up, with additional telephonic follow-up performed at 2 years. The clinical outcomes were correlated with the sST2 values obtained at the time of initial hospitalization. Results: HF was ischemic in origin in 82.0% patients. The primary outcome occurred in 9.3% patients at the end of 1-year follow-up and in 16.7% patients at the end of 2 years. The patients who had events had significantly higher NT-proBNP and sST2 values, but there was no difference in the clinical characteristics, cause of HF, baseline LVEF, or serum creatinine. The patients with elevated sST2 levels (>35 ng/mL) had substantially higher event rates than those with normal sST2 levels (13.7% vs 0.0% at 1-year, P = 0.005; 22.5% vs 4.2% at 2-years, P = 0.004). On multivariate analysis, sST2 was the strongest predictor of adverse outcomes at both 1-year and 2-year follow-ups. Conclusion: In patients hospitalized for HF, elevated sST2 >35 ng/mL at the time of initial hospitalization was associated with significantly high mortality over a 2-year period. The prognostic value of sST2 was incremental to that of NT-proBNP. These findings suggest that a single elevated sST2 value at the time of hospitalization should alert the physicians about the high risk of adverse outcomes and should help facilitate timely intensification of HF treatment. Keywords: ST2, Heart failure, Biomarkers, BNP, NT-ProBNP, Natriuretic peptides