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 (χ(2) = 11.9, P =.0001) was the strongest independent predictor of death or urgent transplantation, followed by serum sodium (χ(2) = 8, P =.0046), resting heart rate (χ(2) = 7.5, P =.0062), plasma endothelin-1 (χ(2) = 7.2, P =.007), and peak VO2 (χ(2) = 6.2, P =.0 12). 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 x kg(-1) x 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 less than or equal to 137 pg/mL (P =.008). Furthermore, plasma BNP was the only independent predictor of sudden death (chi(2) = 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.