BNP is stable in a blood sample for only 4-6 hours while NT-proBNP is stable for days. In order to address the stability issue, BNP can be collected in different sample tubes (EDTA or fluoride-citrate); however this often requires more blood samples to be taken and therefore makes the process more complex and open to error as well as being more resource intensive. Samples for NT- proBNP testing can be collected in standard serum tube with the rest of the Chronic Heart Failure Monitoring NICE 2018. All rights reserved. Subject to Notice of rights. ISBN: 978-1-4731-3093-7 Recommendations Consider measuring NT-proBNP (N-terminal pro-B-type natriuretic peptide) as part of a treatment optimisation protocol only in a specialist care setting for people aged under 75 who have heart failure with reduced ejection likely requests. Because NT-proBNP testing is likely to produce more reliable results than BNP testing, the committee agreed that where NP monitoring is conducted, NT-proBNP should be the peptide measured. Impact of ejection fraction The committee then discussed whether the recommendation should be limited to people with heart failure with reduced (HFREF), rather than preserved (HFpEF), ejection fraction. Although the results of the review were not formally split into HFREF and HFpEF, the committee acknowledged that a substantial majority of the patients in the included studies had HFREF. Because the committee agreed that NP monitoring would have greatest benefit as part of a treatment optimisation protocol, and there was no evidence for long term prognostic benefit from pharmaceutical treatment in HFPEF, it was unlikely that patients with HFPEF would receive significant benefit from NP monitoring. This aligned with subgroup analyses reported in the existing meta-analyses, 279 55 which showed that the mortality and all- cause hospitalisation benefit of NP monitoring was found in HFREF but not HFPEF patients. 