Clinical profile and prognostic significance of natriuretic peptide trajectory following hospitalization for worsening chronic heart failure: findings from the ASTRONAUT trial.

ABSTRACT

AIMS: The purpose of this study was to determine the prognostic significance and associated clinical profile of early post-discharge N-terminal pro-B-type natriuretic peptide (NT-proBNP) trajectory among patients hospitalized for worsening chronic heart failure (HHF). METHODS AND RESULTS: This post-hoc analysis of the Aliskiren Trial in Acute Heart Failure Outcomes (ASTRONAUT) included 1351 HHF patients with ejection fraction (EF) ≤40%, elevated B-type natriuretic peptide ≥400 pg/mL or NT-proBNP ≥1600 pg/mL at admission, and available NT-proBNP measurements (from a central core laboratory) at baseline (median 5 days after admission) and 1-month follow-up. The co-primary endpoints were all-cause mortality and cardiovascular mortality or HHF within 12 months. Median follow-up was 11.3 months. Patients with decreasing post-discharge NT-proBNP trajectory tended to be younger and have non-ischaemic HF aetiology. The presence of baseline atrial fibrillation was associated with high NT-proBNP at 1 month (i.e. above the median), regardless of the baseline value. After adjustment for patient characteristics and 1-month NT-proBNP level, every twofold increase in continuous NT-proBNP change from baseline to 1 month was predictive of increased cardiovascular mortality or HHF (hazard ratio 1.14; 95% confidence interval 1.02-1.26), but not all-cause mortality (hazard ratio 0.95; 95% confidence interval 0.81-1.11). CONCLUSION: In this cohort of HHF patients with reduced EF, early post-discharge NT-proBNP trajectory was associated with a distinct clinical profile and carried independent prognostic value after adjustment for patient characteristics and absolute NT-proBNP level. Future prospective study of serial NT-proBNP measurement during the hospital and early post-discharge periods is warranted to validate these findings and evaluate post-discharge NT-proBNP trajectory as a therapeutic target.