title: Impact of using different guideline recommended serum natriuretic peptide thresholds on the diagnosis and referral rates of a diagnostic heart failure clinic.
abstract: OBJECTIVE
  The aims of this study were to determine the diagnostic yield of a dedicated heart failure diagnosis clinic and the impact of using different guideline recommended N-terminal pro B-type natriuretic peptide (NT-proBNP) referral thresholds on diagnosis and referral patterns.
  
  
  RESULTS
  Patients referred by primary care between September 2011 and May 2013 were included in the analysis. Data collected included baseline characteristics, NT-proBNP levels, echocardiographic and clinical findings, final diagnosis and outcome. The impact of using Newcastle (locally modified age-adjusted NT-proBNP thresholds), National Institute for Health and Care Excellence (NICE) and European Society of Cardiology (ESC) NT-proBNP thresholds on diagnosis and referrals was determined by applying the different guidelines to this population. A total of 208 patients were referred; median age 77.5 years and 62.5% were women. Thirty-four patients (16.3%) had systolic heart failure, 50 patients (24.0%) had heart failure with preserved ejection fraction. One hundred and six patients (51.0%) did not have heart failure. Using NICE guidelines (NT-proBNP ≥ 400 ng/l) instead of the Newcastle age-adjusted NT-proBNP referral thresholds results in 59 fewer referrals, but eight heart failure diagnoses were missed. Using the ESC cut-off of NT-proBNP ≥ 125 ng/l would result in 88 additional referrals; one diagnosis of heart failure would be missed. Over a mean follow-up of 16.8 ± 6 months there were 21 deaths and 47 hospital admissions.
  
  
  CONCLUSIONS
  The Newcastle age-adjusted thresholds led to more referrals in comparison to NICE guidelines but are more sensitive in diagnosing heart failure. Using ESC recommended thresholds results in a similar diagnostic yield to our age-adjusted thresholds, but has the potential to significantly increase the referrals in patients ≥ 75 years, which may result in a lower diagnostic yield.
authors.affiliation: Department of Cardiology, Freeman Hospital, Newcastle upon Tyne, UK.
authors.forename: I A
authors.initials: IA
authors.lastname: Fazal
authors.affiliation: Department of Cardiology, Freeman Hospital, Newcastle upon Tyne, UK.
authors.forename: S K
authors.initials: SK
authors.lastname: Bhagra
authors.affiliation: Department of Cardiology, Royal Victoria Infirmary, Newcastle upon Tyne, UK.
authors.forename: K M
authors.initials: KM
authors.lastname: Bailey
authors.affiliation: Department of Cardiology, Royal Victoria Infirmary, Newcastle upon Tyne, UK.
authors.forename: R
authors.initials: R
authors.lastname: Dermot Neely
authors.affiliation: Department of Cardiology, Freeman Hospital, Newcastle upon Tyne, UK.
authors.forename: G A
authors.initials: GA
authors.lastname: MacGowan
authors.affiliation: Department of Cardiology, Royal Victoria Infirmary, Newcastle upon Tyne, UK.
authors.forename: J S
authors.initials: JS
authors.lastname: Skinner
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D003951:Diagnostic Errors / Q000706:statistics & numerical data; D005260:Female; D006333:Heart Failure / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D017410:Practice Guidelines as Topic; D012016:Reference Values; D012017:Referral and Consultation / Q000706:statistics & numerical data
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain