Longitudinal profile of NT-proBNP levels in ischemic heart failure patients undergoing surgical ventricular reconstruction : the Biomarker Plus study

BACKGROUND: Plasma concentrations of natriuretic peptides have been shown to predict prognosis in heart failure (HF) patients with left ventricle (LV) dysfunction. It is still unclear if measurements after cardiac surgery are associated with any effect on the outcome. We aimed to prospectively investigate the longitudinal profile of serial evaluations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in ischemic HF patients undergoing Surgical Ventricular Reconstruction (SVR) and how NT-proBNP levels at different time-points are associated with the outcome. METHODS: One hundred and forty-three patients (122 men, 64 ± 9 years old) with post-infarction LV remodeling referred to our Center for SVR had an assessment of NT-proBNP levels before surgery and 6, 12 and 18 months after surgery. The analysis was performed using the logarithm of the biomarker and joint modeling of serial measurements through mixed models together with Cox regression to analyze time to event data. RESULTS: The average level of the biomarker decreased by about 50% during the first year after the operation. Time-varying NT-proBNP levels were associated with the hazard of: 1% increase in NT-proBNP during the follow-up was associated with 1.5% increase of the risk of the composite event (95% CI: 1.0%, 2.6%) and with 4.2% increase of the risk of death (95% CI: 2.2%, 8.2%). CONCLUSIONS: Serial profiles (either in increasing or in decreasing) at different time points are associated with a modulation of the risk of adverse events and, therefore, are important indicators for monitoring the evolution of the disease, even after cardiac surgery.