Combination of B-type natriuretic peptide and peak oxygen consumption improves risk stratification in outpatients with chronic heart failure

Background Peak oxygen consumption is a cornerstone for prognostic determination in patients with congestive heart failure. The purpose of this study was to assess whether plasma B-type natriuretic peptide (BNP) provided any additional prognostic information. Methods Plasma concentrations of atrial natriuretic peptide, N terminal pro-atrial natriuretic peptide, BNP, endothelin-1, norepinephrine, and peak VO2 were measured in 250 consecutive outpatients with mild to moderate heart failure (96% in New York Heart Association [NYHA] class II or III) and left ventricular ejection fraction (LVEF) <45%. Results During a median follow-up of 584 days, 42 patients died (19 from sudden death) and 5 underwent urgent heart transplantation. Multivariate stepwise regression analysis showed that, among 13 variables including NYHA and LVEF, plasma BNP (χ2 = 11.9, P = .0001) was the strongest independent predictor of death or urgent transplantation, followed by serum sodium (χ2 = 8, P = .0046), resting heart rate (χ2 = 7.5, P = .0062), plasma endothelin-1 (χ2 = 7.2, P = .007), and peak VO2 (χ2 = 6.2, P = .012). Patients with plasma BNP above the upper quartile value (260 pg/mL) had a 1-year rate of death or urgent transplantation of 31%. The 1- and 2-year survival rates without urgent transplantation in patients with a peak VO2 ≤14 mL × kg−1 × min−1 were 71% and 59%, respectively, when plasma BNP was >137 pg/mL (median value), compared with 100% and 89%, respectively, when plasma BNP was ≤137 pg/mL (P = .008). Furthermore, plasma BNP was the only independent predictor of sudden death (χ2 = 19.9, P = .00001). Conclusions Plasma BNP provides additive independent prognostic information compared to peak VO2 alone in outpatients with mild to moderate heart failure.