Combined use of the novel biomarkers high-sensitivity troponin T and ST2 for heart failure risk stratification vs conventional assessment

Abstract

Objective: To assess an innovative multimarker strategy for risk stratification of death in a real-life ambulatory heart failure (HF) cohort.

Patients and methods: The study included 876 consecutive outpatients (median age, 70.3 years; left ventricular ejection fraction, 34%) between May 22, 2006, and July 7, 2010, prospectively followed up in a structured HF unit. A combination of biomarkers reflecting myocardial stretch (N-terminal pro-B-type natriuretic peptide [NT-proBNP]), myocyte injury (high-sensitivity cardiac troponin T [hs-cTnT]), and ventricular fibrosis and remodeling (high-sensitivity ST2 [hs-ST2]) were added to an assessment based on established mortality risk factors (age, sex, left ventricular ejection fraction, New York Heart Association functional class, diabetes mellitus, estimated glomerular filtration rate, ischemic etiology, sodium level, hemoglobin level, and pharmacologic treatment).

Results: During median follow-up of 41.4 months, 311 patients died. The combined addition of hs-cTnT and hs-ST2 to the model yielded good measurements of performance (C statistic, 0.789; Bayesian information criterion, 3611; integrated discrimination improvement, 4.1 [95% CI, 2.5-5.6]; and net reclassification index, 13.9% [95% CI, 6.2-21.6]). Reclassification did not significantly benefit after NT-proBNP addition into the full model; some indices even worsened with all 3 biomarkers. Separate addition of NT-proBNP provided prognostic discrimination only in the subgroup of patients with either hs-cTnT or hs-ST2 levels below the cutoff points (hazard ratio, 2.97; 95% CI, 2.24-9.39; P<.001).

Conclusion: A multimarker strategy seems useful for stratifying risk in chronic HF. However, NT-proBNP in addition to the new-generation biomarkers hs-cTnT and hs-ST2 had a limited effect on risk stratification.