B-type natriuretic peptide and C-terminal-pro-endothelin-1 for the prediction of severely impaired peak oxygen consumption

Abstract

Maeder MT, Brutsche MH, Staub D, Morgenthaler NG, Bergmann A, Noveanu M, Laule K, Breidthardt T, Christ A, Klima T, Reichlin T, Potocki M, Mueller C (University Hospital Basel, Switzerland; Baker IDI Heart and Diabetes Institute, Melbourne, Australia; and Biotechnology Center, Henningsdorf/Berlin, Germany). B-type natriuretic peptide and C-terminal-pro-endothelin-1 for the prediction of severely impaired peak oxygen consumption. J Intern Med 2009; 265:604-615.Objective. To assess the utility of B-type natriuretic peptide (BNP) and C-terminal-pro-endothelin-1 (CT-proET-1) to predict a severely impaired peak oxygen consumption (peak VO2, < 14 mL kg-1 min-1) in patients referred for cardiopulmonary exercise testing. Design. Cross-sectional study. Setting. Tertiary care center. Methods. Peak VO2, BNP and CT-proET-1 were assessed in 141 consecutive patients referred for cardiopulmonary exercise testing. Results. B-type natriuretic peptide [median (interquartile range) 48 (38-319) vs. 33 (15-86) pg mL -1; P = 0.002] and CT-proET-1 [87 (76-95) vs. 60 (52-74) pmol L -1; P < 0.001] were higher in patients with a peak VO2 < 14 mL kg-1 min-1 (n = 30) than in those with a peak VO2 ≥ 14 mL kg-1 min-1 (n = 111). CT-pro-ET-1 had a higher area under the receiver-operator-characteristics curve (AUC) to predict a peak VO2 < 14 mL kg-1 min -1 than BNP (0.79 vs. 0.68; P = 0.04). The optimal BNP cut-off of 37.2 pg mL-1 had a sensitivity of 80% and a specificity of 56%. The optimal CT-proET-1 cut-off of 74.4 pmol L-1 had a sensitivity of 80% and specificity of 76%. A five-item score composed of body mass index, diabetes, forced expiratory volume within the first second, alveolo-arterial oxygen pressure difference, and BNP had an AUC of 0.88 to predict a peak VO2 < 14 mL kg-1 min-1. Adding CT-proET-1 to the score resulted in an AUC of 0.92. Conclusions. C-terminal-pro-endothelin-1 is superior to BNP for the prediction of a peak VO2 < 14 mL kg-1 min-1 in patients referred for CPET. A score incorporating body mass index, diabetes status, spirometry, blood gases, BNP and CT-proET-1 improves the prediction of a peak VO2 < 14 mL kg-1 min-1 based on single biomarkers. © 2009 Blackwell Publishing Ltd.