Abstract 19363: Prognostic Ability of VE/VCO2 Slope in Combination With Serum BNP Levels in Patients with Heart Failure
Background: Exercise testing with ventilatory expired gas analysis has proven to be a valuable tool for assessing patients with heart failure (HF). Peak oxygen consumption continues to be considered the gold standard for assessing prognosis in HF. The minute ventilation-carbon dioxide production relationship (VE/VCO2 slope) has recently demonstrated prognostic significance in patients with HF, and classification system using the value is proposed to improve clinical decision making in HF (Circulation 2007;115:2410). While serum BNP levels are recognized as a useful biomarker to diagnose HF.
Methods and Results: To obtain better prognosis evaluating system of HF using exercise testing with ventilatory expired gas analysis, VE/VCO2 slope was used in combination with serum BNP measured simultaneously with exercise test. From June 2008 to December 2009, consecutive 241 HF patients (male 80%, mean age 65y) who underwent symptom limited cardiopulmonary exercise testing and BNP measurement at the same time were followed up for 653 days prospectively. Primary endpoint was any cause of death and HF needed emergent rehospitalization. Patients were divided into 4 groups according to the high and low values of VE/VCO2 slope and BNP in 2x2 fashion. Primary endpoint events occurred in 9.5% of the study subjects. Multivariate analysis revealed that only age and VE/VCO2 slope were significant predictors of the event. Kaplan-Meier estimates revealed that patients with both higher VE/VCO2 slope (≥36) and BNP (≥150) had the worst prognosis (Figure). There were significant differences in event rates between high and low VE/VCO2 slope groups in high BNP subgroup (p=0.0093), however, that was not the fact anymore in the low BNP subgroup.
Conclusions: Solely VE/VCO2 slope cannot predict prognosis of HF enough in those with low BNP in particular. VE/VCO2 slope could be a strong predictor of HF in combination with serum BNP levels measured simultaneously with exercise test.
- © 2010 by American Heart Association, Inc.