Chemistry, toxicology & urinalysis
Organ specific
Cardiac
Natriuretic peptides (BNP and Amino-terminal proBNP)
Author: Larry Bernstein, M.D.
Last author update: 1 December 2010
Last staff update: 6 April 2020
Copyright: 2002-2024, PathologyOutlines.com, Inc.
PubMed Search: Natriuretic peptides [title]
Cite this page: Bernstein L. Natriuretic peptides (BNP and Amino-terminal proBNP). PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/chemistrycardiacnatriuretic.html. Accessed December 18th, 2024.
Definition / general
- Brain natriuretic peptide (BNP), now known as B-type natriuretic peptide (also BNP), is a 32 amino acid polypeptide secreted by the cardiac ventricles in response to excessive stretching of cardiomyocytes (Wikipedia - Brain natriuretic peptide)
- BNP was originally identified in extracts of porcine brain, although in humans it is produced mainly in the cardiac ventricles
- BNP is co-secreted with a 76 amino acid N-terminal fragment (NT-proBNP), which is biologically inactive
Clinical features
- Reduces misdiagnosis of congestive heart failure, which occurs 50% to 75% of the time
- NT-proBNP is superior to BNP for predicting mortality and morbidity for heart failure (Clin Chem 2006;52:1528), and coexisting renal disease and heart failure (Clin Chem 2007;53:1511)
Laboratory
Indications
Reference ranges
Limitations
- Evaluation of dyspneic patient with suspected congestive heart failure, regardless of renal function (J Am Coll Cardiol 2006;47:91)
- B-type natriuretic peptide levels are higher in patients with congestive heart failure than in dyspnea from other causes (J Am Coll Cardiol 2002;39:202, N Engl J Med 2004;350:647)
- NT-proBNP measurement is a valuable addition to standard clinical assessment for the identification and exclusion of acute CHF in the emergency department setting (Am J Cardiol 2005;95:9480)
Reference ranges
- BNP levels below 100 pg/mL indicate no heart failure
Limitations
- Determination of endogenous BNP with the AxSYM assay using frozen plasma samples may not be valid after 1 day, but NT-proBNP as measured by the Elecsys assay may be stored at -20 degrees C for at least four months without a relevant loss of the immunoreactive analyte (Clin Chem Lab Med 2004;42:942)
