The role of B-type natriuretic peptide testing in patients with acute coronary syndromes.

B-type (brain) natriuretic peptide (BNP) is a cardiac hormone whose measurement can be helpful in a variety of clinical settings, but has been most extensively studied in patients with heart failure and acute coronary syndrome (ACS). The value of both BNP and its N-terminal fragment, NT-proBNP, as independent prognostic biomarkers in ACS is supported by data from a number of clinical trials. BNP/NT-proBNP levels can predict death and subsequent development of heart failure, but not recurrent ischemic events. BNP may also be helpful as an aid in establishing the diagnosis of ACS in patients presenting with chest pain. The role of BNP in determining treatment has not yet been defined, though patients with high levels may derive more benefit from invasive management and from treatment with ranolazine. The National Academy of Clinical Biochemists (NACB) guidelines state that measurement of BNP/NT-proBNP may be useful in prognosis for ACS patients, but do not yet recommend its routine use, naming a number of other issues that need to be resolved in the use of this marker. Age- and gender-related decision limits should be determined, and cutoff levels of BNP/NT-proBNP corresponding to low, intermediate, and high risk patients should be ascertained. Additional evidence regarding the impact of BNP/NT-proBNP levels on treatment strategy in ACS patients will be helpful in further defining the role of B-type natriuretic peptide testing in the acute coronary syndromes.