PF-PTD-53
BNP (NT-proBNP)
Synonyms N-terminal pro-b-type natriuretic peptide
Clinical Indication Pro B-type natriuretic peptide (BNP) is released from the cardiac ventricles in
response to stretching of the chamber and is cleaved to form biologically
active BNP and N-terminal pro-BNP (NT-proBNP).
It has been introduced to 'rule-out' suspected heart failure and help select
patients requiring cardiac imaging. It is important that it is only requested in
patients meeting specific criteria otherwise many 'false positive' results may
be generated which will need follow-up cardiac imaging.
BNP analyses are only available to GPs for investigation of new cases of
suspected heart failure. ECG and chest X-ray should have been undertaken
and anaemia, renal, liver and thyroid dysfunction excluded.
BNP is also available at Basildon Hospital for A&E/MAU patients on admission
with suspected Acute Heart Failure (see pathway); and at Southend Hospital
for AMU and Ambulatory Care wards.
These requests are usually initiated by the Heart Failure team.
Part of Profile / See Also N/A
Request Form Combined Pathology manual Blood form or ICE request
Availability / Frequency of Analysed if requested by GP or specific criteria met.
Analysis Minimum retesting interval is 12 months.
Turnaround Time Same day.
Patient Preparation None required
Sample Requirements
Specimen Type Serum
Volume 2 ml
Container
Yellow top (SST) tube
Reference Range & Units < 300 ng/L <75 years age
< 450 ng/L if 75 years age or over
Interferences None
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PF-PTD-53
Interpretation & Clinical Basildon patients – hospital or primary care:
Decision Value (if applicable) BNP result Interpretive comment
≤400 ng/L Diagnosis of heart failure unlikely.
401-899 ng/L and Please correlate with clinical signs and symptoms to
patient ≥75y determine if further investigations or referral is
required.
401-1999 ng/L and Refer for open access echocardiogram with the
patient <75y presence of supporting clinical signs and symptoms.
900-1999 ng/L and Refer for open access echocardiogram with the
patient ≥75y presence of supporting clinical signs and symptoms.
≥2000 ng/L Refer immediately for open access echocardiogram.
Southend patients – hospital or primary care:
BNP result Interpretive comment
≤400 ng/L This patient is not suitable for the One-stop service.
Please refer via the normal route to cardiology if you
are still concerned regarding heart failure.
401-899 ng/L and This patient is not suitable for the One-stop service.
patient ≥75y Please refer via the normal route to cardiology if you
are still concerned regarding heart failure.
401-899 ng/L and Patient will be automatically referred to the One stop
patient <75y service within 6 weeks if the patient has not had an
echo or cardiology review in the last 2 years.
900-1999 ng/L Patient will be automatically referred to the One stop
service within 4 weeks if the patient has not had an
echo or cardiology review in the last 2 years.
≥2000 ng/L Patient will be automatically referred to the One-stop
service within 2 weeks if the patient has not had an
echo or cardiology review in the last 2 years.
References NICE CG108 Chronic heart failure in adults: management
NICE CG187 Acute heart failure: diagnosis and management
Test code BNP
Lab Handling Analysed from primary tube and stored at 4°C. Stable for 6 days 2-8 °C.
Version 1.6 / September 2021 Approved by: Consultant Biochemist Page 2 of 2
