Patients were included in this study in 2010. All patients gave informed consent. Clinical characteristics were registered and biomarkers were assessed. Clinical outcomes were registered regularly by a clinical follow-up or by phone by a dedicated physician. We use the prognostic score of Lupon et al. including clinical data, NT pro-BNP, hs-c TnT and SST2 assay. Survival curves were built and data presented as means±SD when normally distributed.
180 patients (mean age 72.5y±12.5y) were included. Left ventricular ejection fraction was 37.1%±14.2%. ST2 concentrations are strongly predictive of all cause mortality [HR 3.15 (95% CI: 1.46-6.8)] and cardiovascular mortality [HR 4.28 (95% CI: 1.5-12.26)] regardless of NT pro-BNP concentrations. Estimation of the risk of all-cause and cardiovascular mortality was significantly improved by adding SST2, NT pro-BNP and hs-c TnT levels to clinical covariates. Risk of mortality was estimated using Cox proportionnal hazard models. Discrimination, assessed by c-index, rose from 0.678 for the clinical model to 0.715 after addition of biomarkers for prediction of all-cause mortality. For cardiovascular mortality, c-index was improved from 0.703 to 0.753. Added value of biomarkers was also evaluated by reclassification analysis. Associated net reclassification improvement (NRI) [95% CI] for 48 months death were 0.395 [0.068-0.653], p=0.033 and 0.395 [0.068-0.653], p=0.020 for all cause and cardiovascular death, respectively.
SST2 appears as a promising prognostic biomarker. It could provide additional information to natriuretic peptides