title: Low NT-proBNP levels: An early sign for the diagnosis of ischemic heart failure.
abstract: BACKGROUND
  N-terminal pro-brain natriuretic peptide (NT-proBNP) is seen to be mostly elevated in patients with acute heart failure (AHF). However, cases of AHF presenting with low NT-proBNP levels have been reported. In this study designed to investigate the factors associated with low NT-proBNP levels in AHF patients, we discovered that etiology and related factors have an influence on NT-proBNP levels.
  
  
  METHODS
  In this study, 154 AHF patients met the study criteria (117 men, median age 74years; left ventricular ejection fraction [LVEF] 46±13%; New York Heart Association [NYHA] classes II-IV). We analyzed the different clinical variables of patients based on plasma NT-proBNP levels. In addition, we identified the differences in NT-proBNP levels between ischemic and non-ischemic etiologies, as well as the relationships between time from symptom onset to ED visit and NT-proBNP levels.
  
  
  RESULTS
  The group with low NT-proBNP levels showed an ischemic association, higher LVEF, lower NYHA class and shorter time from symptom onset to ED visit. Plasma NT-proBNP levels were lower in the ischemic group than in the non-ischemic group (P<0.01). Meanwhile, NT-proBNP levels were relatively low in patients during early phases of AHF hospitalization and increased with time from symptom onset to ED visit (P<0.01).
  
  
  CONCLUSIONS
  We inferred that low NT-proBNP levels may infer the ischemic etiology especially in patients with normal LVEF in the early phases of AHF hospitalization.
authors.affiliation: Department of Cardiology, Zhejiang Provincial People's Hospital, China.
authors.forename: Ya-Ru
authors.initials: YR
authors.lastname: Zheng
authors.affiliation: Department of Cardiology, Zhejiang Provincial People's Hospital, China.
authors.forename: Li-Fang
authors.initials: LF
authors.lastname: Ye
authors.affiliation: Department of Cardiology, Zhejiang Provincial People's Hospital, China.
authors.forename: Xue-Jiang
authors.initials: XJ
authors.lastname: Cen
authors.affiliation: Department of Cardiology, Zhejiang Provincial People's Hospital, China.
authors.forename: Jing-Yang
authors.initials: JY
authors.lastname: Lin
authors.affiliation: Department of Cardiology, Zhejiang Provincial People's Hospital, China.
authors.forename: Jian-Wei
authors.initials: JW
authors.lastname: Fu
authors.affiliation: Department of Cardiology, Zhejiang Provincial People's Hospital, China. Electronic address: wanglhnew@126.com.
authors.forename: Li-Hong
authors.initials: LH
authors.lastname: Wang
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers; D015331:Cohort Studies; D004636:Emergency Service, Hospital; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000097:blood* / Q000150:complications / Q000175:diagnosis*; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D013318:Stroke Volume
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
keywords: Acute heart failure; Ischemic etiology; N-terminal pro-brain natriuretic peptide; Time interval