RT Journal Article SR Electronic T1 Primary care REFerral for EchocaRdiogram (REFER) in heart failure: a diagnostic accuracy study JF British Journal of General Practice JO Br J Gen Pract FD British Journal of General Practice SP bjgpfeb-2017-67-655-taylor-fl-oa-p DO 10.3399/bjgp16X688393 A1 Clare J Taylor A1 Andrea K Roalfe A1 Rachel Iles A1 FD Richard Hobbs A1 Pelham Barton A1 Martin R Cowie A1 Russell C Davis A1 Jon Deeks A1 Jonathan Mant A1 Deborah McCahon A1 Theresa McDonagh A1 George Sutton A1 Lynda Tait YR 2016 UL http://bjgp.org/content/early/2017/01/12/bjgp16X688393.abstract AB Background Symptoms of breathlessness, fatigue, and ankle swelling are common in general practice but deciding which patients are likely to have heart failure is challenging.Aim To evaluate the performance of a clinical decision rule (CDR), with or without N-Terminal pro-B type natriuretic peptide (NT-proBNP) assay, for identifying heart failure.Design and setting Prospective, observational, diagnostic validation study of patients aged >55 years, presenting with shortness of breath, lethargy, or ankle oedema, from 28 general practices in England.Method The outcome was test performance of the CDR and natriuretic peptide test in determining a diagnosis of heart failure. The reference standard was an expert consensus panel of three cardiologists.Results Three hundred and four participants were recruited, with 104 (34.2%; 95% confidence interval [CI] = 28.9 to 39.8) having a confirmed diagnosis of heart failure. The CDR+NT-proBNP had a sensitivity of 90.4% (95% CI = 83.0 to 95.3) and specificity 45.5% (95% CI = 38.5 to 52.7). NT-proBNP level alone with a cut-off <400 pg/ml had sensitivity 76.9% (95% CI = 67.6 to 84.6) and specificity 91.5% (95% CI = 86.7 to 95.0). At the lower cut-off of NT-proBNP <125 pg/ml, sensitivity was 94.2% (95% CI = 87.9 to 97.9) and specificity 49.0% (95% CI = 41.9 to 56.1).Conclusion At the low threshold of NT-proBNP <125 pg/ml, natriuretic peptide testing alone was better than a validated CDR+NT-proBNP in determining which patients presenting with symptoms went on to have a diagnosis of heart failure. The higher NT-proBNP threshold of 400 pg/ml may mean more than one in five patients with heart failure are not appropriately referred. Guideline natriuretic peptide thresholds may need to be revised.