Three sites provided unit cost information for BNP, and five sites provided unit cost information for NTproBNP. The average of these are reported below. Table 14: Cost of natriuretic peptide tests Test Unit cost 5.1.5.3 New cost-effectiveness analysis The committee identified this area as a priority for original economic analysis. The committee sought to determine whether natriuretic peptide testing is cost-effective and if so what the most cost- effective diagnostic threshold should to refer for echocardiography and specialist clinical assessment. In recent years the European Society of Cardiology (ESC) has lowered their recommended natriuretic peptide thresholds from 100pg/ml for BNP and 400pg/ml for NT-proBNP to 35pg/ml (BNP) and 125pg/ml respectively, due to concern that previously recommended thresholds were too high. The committee also raised concerns that the threshold recommended in the 2010 Chronic Heart Failure (CHF) guideline (which was in line with the previous ESC thresholds) may be too high, resulting in some patients with heart failure receiving a delayed diagnosis and either re-presenting to primary care at a later date with worsening symptoms or presenting to hospital due to a decompensation. Lowering the threshold could also allow for earlier diagnosis and a better prognosis of these patients. However, the committee also noted that lowering the threshold may greatly increase cost to the NHS due to the greater number of referrals for echocardiography and specialist clinical assessment, many of which are unlikely to lead to a diagnosis of heart failure and therefore the diagnosis of other possible underlying conditions could be delayed. Therefore, original cost-effectiveness modelling was undertaken for this question. A summary is included here. Evidence statements summarising the results of the analysis can be found below. The full analysis can be found in Appendix O. 