Norepinephrine, plasma renin activity and cardiovascular mortality in systolic heart failure

OBJECTIVE: We analysed the circulating levels and prognostic value of N-terminal pro-B-type natriuretic peptide (NT-proBNP), norepinephrine (NE), epinephrine (E), plasma renin activity (PRA) and aldosterone in patients with systolic heart failure (HF) receiving therapies that target the sympathetic system and the renin-angiotensin-aldosterone axis. METHODS: We retrieved data from consecutive HF outpatients with left ventricular ejection fraction (LVEF) <50% and available neurohormones, evaluated at a tertiary referral centre for HF from 1999 to 2016. RESULTS: Patients (n=1477) were aged 66±13 years, 75% were men, median LVEF was 32% (IQR 25-38), 77% had LVEF <40% and 44% ischaemic HF. At the time of sampling, 69% were on beta-blockers, 75% on ACE inhibitors/angiotensin receptor blockers and 48% on mineralocorticoid receptor antagonists vs 88%, 87% and 66%, respectively, after therapy optimisation. Median NT-proBNP, NE, E, PRA and aldosterone were 1441 ng/L, 494 ng/L, 30 ng/L, 1.2 ng/mL/hour and 130 ng/dL, respectively. Over a 4.8-year follow-up (2.4-8.2), 376 patients died from cardiovascular causes (26%). NT-proBNP and PRA predicted cardiovascular mortality after adjusting for all other univariable predictors. The risk of cardiovascular death increased by 8% or 7% per each doubling of PRA in 2 models considering therapies at the time of sampling or after therapy optimisation. PRA improved metrics of reclassification and discrimination, and independently predicted outcome even in the LVEF <40% subgroup. CONCLUSIONS: In patients with HF with LVEF <50% or <40%, PRA shows independent prognostic significance from a model that includes NT-proBNP, and might represent an additive tool for risk stratification.