Usefulness of Brain Natriuretic Peptide Level at Implant in Predicting Mortality in Patients with Advanced But Stable Heart Failure Receiving Cardiac Resynchronization Therapy

Abstract

Brain natriuretic peptide (BNP) level has emerged as a predictor of death and hospital readmission in patients with heart failure (HF). The value of baseline BNP assessment in advanced HF patients receiving cardiac resynchronization defibrillator therapy (CRT-D) has not been firmly established. We hypothesized that a baseline BNP level would predict all cause mortality and HF hospitalization in HF patients receiving cardiac resynchronization therapy. A retrospective chart review of all patients having BNP assessment prior to implantation of a CRT-D for standard indications during 2004 and 2005 was conducted at the Veterans Affairs Pittsburgh Healthcare System. The primary endpoint was all-cause mortality and the secondary endpoint was HF-related hospitalization. We used findings from the receiver operating characteristic (ROC) curve to define low (<492 pg/mL) and high (> or =492 pg/mL) BNP groups. Out of 173 CRT-D recipients, 115 patients (mean age 67.0 +/- 10.7 years, New York Heart Association [NYHA] class 2.9 +/- 0.3, left ventricular ejection fraction [LVEF] 22.5% +/- 9.6%, QRS 148.3 +/- 30.4 ms) had preimplantation BNP measured (mean 559 +/- 761 pg/mL and median 315 pg/mL). During a mean follow-up time of 17.5 +/- 6.5 mo, 27 deaths (23.5%) and 31 HF hospitalizations (27.0%) were recorded. Compared to those with low BNP (n = 74), those of high BNP (n = 41) were older, had lower LVEF, higher creatinine levels, suffered more deaths, and HF hospitalizations. In multivariate regression models, higher BNP remained a significant predictor of both the primary endpoint (hazard ratio [HR]: 2.89, 95% confidence interval [CI] 1.06-7.88, p = 0.038) and secondary endpoint (HR: 4.23, 95% CI: 1.68-10.60, p = 0.002). Baseline BNP independently predicted mortality and HF hospitalization in a predominantly older white male population of advanced HF patients receiving CRT-D. Elevated BNP levels may identify a vulnerable HF population with a particularly poor prognosis despite CRT-D.