B-type natriuretic peptides: applications for heart failure management in 2005.

摘要

B-type or brain natriuretic peptide (BNP) was discovered in 1988 and since then a large body of research has demonstrated its important role in regulating cardiorenal function and as a powerful cardiac biomarker.BNP and the amino-terminal portion of its pro-hormone (NT-ProBNP) are secreted predominantly from the left ventricle (LV) in response to increased wall stress and volume or pressure overload. BNP is a natriuretic, vasodilator and anti-mitogenic hormone with a pivotal counter-regulatory role in maintaining cardiorenal function in health and disease states.Both BNP and NT-ProBNP can be detected in plasma and commercial assays are available for each, with levels commonly reported in SI units (pmol/L), but increasingly in pg/mL (convert from pmol/L by multiplying by 3.45 for BNP and 8.5 for NT-ProBNP). There is equimolar secretion of BNP and NT-ProBNP, hence plasma levels are tightly correlated but are higher for NT-ProBNP by five-tenfold, due mainly to its longer plasma half-life compared to BNP, which is actively metabolized by neutral endopeptidase and cleared by the NPR-C receptor. Levels of both peptides increase with age and greater renal dysfunction, are higher for women than men and lower in obesity. In heart failure, BNP and NT-ProBNP levels increase in proportion to the severity of cardiac dysfunction and symptoms. Levels reflect LV systolic and diastolic function as well as LV filling pressure and haemodynamically significant structural or valve lesions.