Diagnostic and prognostic impact of brain natriuretic peptide in cardiac and noncardiac diseases.
OBJECTIVE
Cardiac secretion of brain natriuretic peptide (BNP) increases with the progression of congestive heart failure (CHF). The plasma measurement of BNP emerged recently as a useful, cost-effective biomarker for the diagnosis and prognosis of CHF.


METHODS
BNP assay is useful for evaluating patients with acute dyspnea, because a low level can help rule out CHF in primary care settings and reduce the demand for echocardiography. Equally, BNP level can be particularly useful in recognizing heart failure in a patient with acute dyspnea and a history of chronic obstructive pulmonary disease.


RESULTS
However, although the clinical use of BNP as a biomarker in CHF is increasing, the specificity of BNP in CHF is not strong, suggesting that other mechanisms beyond simple ventricular stretch stimulate BNP release. Multiple disorders in the intensive care unit, apart from CHF, cause elevated BNP levels, including cardiovascular disease states such as ischemia, arrhythmias, cardiac hypertrophy, and coronary endothelial dysfunction, as well as disorders of no cardiac origin, such as sepsis, septic shock, and acute respiratory distress syndrome. Moreover, the impact of increased BNP in patients with sepsis is not clear. The relationship between BNP and both left ventricular ejection fraction and left-sided filling pressures is weak, and data on the prognostic impact of high BNP levels in patients with sepsis are conflicting.


CONCLUSIONS
Nevertheless, this review highlights the potential benefits of BNP in the recognition and management of heart failure, and defines the gray zones of BNP levels; it also identifies conditions influencing BNP levels in relation to a certain heart failure and describes conditions of no cardiac origin with increased BNP.
Zakynthinos
Epaminondas
E
Critical Care Department, School of Medicine, University Hospital of Thessaly, Thessaly, Greece.
Kiropoulos
Theodoros
T
Gourgoulianis
Konstantinos
K
Filippatos
Gerasimos
G
D015415:Biomarkers; D002318:Cardiovascular Diseases / Q000097:blood / Q000175:diagnosis; D003937:Diagnosis, Differential; D006333:Heart Failure / Q000175:diagnosis / Q000378:metabolism* / Q000401:mortality; D006801:Humans; D020097:Natriuretic Peptide, Brain / Q000096:biosynthesis* / Q000097:blood* / Q000502:physiology; D011379:Prognosis; D018805:Sepsis / Q000097:blood
D015415:Biomarkers; D020097:Natriuretic Peptide, Brain