[Peak oxygen consumption, NT-proBNP and echocardiographic changes in patients with chronic heart failure].
OBJECTIVE
To assess peak oxygen consumption (peak VO₂) derived from cardiopulmonary exercise testing (CPET), concentrations of NT-proBNP and echocardiographic changes in patients with chronic heart failure (CHF) and reduced left ventricular ejection fraction (LVEF, <40%).


METHODS
Seventy patients were included and divided into two groups according to the New York Heart Association (NYHA) classification: NYHA II group (17 cases) and NYHA III-IV group (53 cases). The basic clinical information, plasma concentration of NT-proBNP at rest, echocardiographic parameters and peak VO₂from CPET were compared between two groups. Correlation among peak VO₂, NT-proBNP and echocardiographic parameters in this patient cohort was assessed and their abilities to discriminate the NYHA III-IV grade were analyzed through c-Statistic.


RESULTS
Left atrial diameter ((51.3 ± 7.2) mm vs. (44.0±7.4) mm, P<0.001) was larger, plasma concentration of NT-proBNP (1 379-4 399 pmol/L vs. 1 109-2 356 pmol/L, P<0.01) was higher and peak VO₂((13.4 ± 3.5) ml·kg⁻¹·min⁻¹ vs. (18.2 ± 3.7) ml·kg⁻¹·min⁻¹, P<0.001) were significantly lower in NYHA III-IV group than those in NYHA II group. However, left ventricular end-diastolic diameter (LVEDD) and LVEF were similar between two groups. Peak VO₂correlated significantly with NT-proBNP (r=-0.311, P<0.01), but neither peak VO₂nor NT-proBNP correlated with echocardiographic parameters (LA, LVEDD and LVEF). ROC analysis showed that peak VO₂had the strongest discriminatory power for detecting NYHA III-IV grade patients (AUC=0.835, P<0.001), followed by the NT-proBNP (AUC=0.723, P<0.01).


CONCLUSIONS
Peak VO₂is a more sensitive parameter to detect the disease aggravation (NYHA III-IV grade) of the CHF patients with reduced LVEF compared to plasma NT-proBNP and echocardiographic parameters (LA, LVEDD, LVEF).
State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China.
Zhinan
Z
Lu
State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China; Email: xgsun@labiomed.org.
Xingguo
X
Sun
State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China.
Shengshou
S
Hu
State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China.
Jie
J
Huang
D002908:Chronic Disease; D004452:Echocardiography; D005080:Exercise Test; D006321:Heart; D006333:Heart Failure; D006801:Humans; D020097:Natriuretic Peptide, Brain; D010101:Oxygen Consumption; D010446:Peptide Fragments; D012372:ROC Curve; D016277:Ventricular Function, Left
D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain