Prognostic Value and Kinetics of Soluble Neprilysin in Acute Heart Failure: A Pilot Study

This study sought to examine the prognostic value of the soluble form of neprilysin (sNEP) in acute heart failure (AHF) and sNEP kinetics during hospital admission.

sNEP was recently identified in chronic heart failure (HF) and was associated with cardiovascular outcomes.

A total of 350 patients (53% women, mean 72.6 ± 10.7 years of age) were included in the study. Primary endpoints were composites of cardiovascular death or HF hospitalizations at short-term (2 months) and long-term (mean: 1.8 ± 1.2 years) follow-up. sNEP was measured using an ad hoc-modified enzyme-linked immunosorbent assay, and its prognostic value was assessed using Cox regression analyses. In a subgroup of patients, sNEP was measured both at admission and at discharge (n = 92).

Median admission sNEP concentrations were 0.67 ng/ml (Q1 to Q3: 0.37 to 1.29), and sNEP was significantly associated, in age-adjusted Cox regression analyses, with the composite endpoint at short-term (hazard ratio [HR]: 1.29; 95% confidence interval [CI]: 1.04 to 1.61; p = 0.02) and long-term (HR: 1.23; 95% CI: 1.01 to 1.05; p = 0.003) follow-up. In multivariate Cox analyses that included clinical variables and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) concentration, sNEP concentration at admission showed a clear trend toward significance for the composite endpoint at 2 months (HR: 1.22; 95% CI: 0.97 to 1.53; p = 0.09) and remained significant at the end of follow-up (HR: 1.21; 95% CI: 1.04 to 1.40; p = 0.01). At discharge, sNEP levels decreased from 0.70 to 0.52 ng/ml (p = 0.06).

Admission sNEP concentration was associated with short- and long-term outcomes in AHF, and dynamic sNEP concentrations were observed during hospital admission. These preliminary data may be hypothesis-generating for the use of NEP inhibitors in AHF.