B-type Natriuretic Peptide (BNP)

I. PURPOSE
The BNP assay is intended for the in vitro diagnostic use in the quantitative determination of B-type Natriuretic Peptide (BNP) in human plasma. This assay is indicated for the measurement of plasma BNP as an aid in the diagnosis and assessment of the severity of heart failure. In patients with acute coronary syndromes (ACS), this test, in conjunction with other known risk factors, can also be used to predict survival as well as to predict the likelihood of future heart failure.


II. BACKGROUND
Heart failure is an important clinical syndrome which compromises left ventricular systolic or diastolic function or a combination of both. Heart failure occurs when the heart is unable to pump blood at a rate sufficient for metabolic requirements. The most common causes are coronary artery disease, hypertension, valvular heart diseases and cardiomyopathies. Accurate and early diagnosis is important since effective therapeutic interventions (e.g., angiotensin converting enzyme inhibitors, beta-blockers) are available, which improve both morbidity and mortality. Studies indicate that BNP can be used for a wide range of clinical applications; including diagnosis, monitoring and prognosis. The circulating levels of BNP increase with decreasing left ventricular function and increasing clinical severity of heart failure, which makes it an appropriate test for diagnosis and staging of heart failure. Studies have also demonstrated that an increased level of circulating BNP correlates with higher incidence of cardiac events and mortality in patients with heart failure and Acute Coronary Syndromes, and supports utilization of BNP as a marker for patient prognosis.