LCD L34410: B-type Natriuretic Peptide (BNP) Testing

B-type natriuretic peptide (BNP) and its precursor amino terminal (NT-proBNP) increase in patients with cardiac disease due to myocardial stress and volume overload as found in heart failure (HF). 3

When used in conjunction with other clinical information, the rapid measurement of levels of BNP or NT-proBNP is useful in establishing or excluding the diagnosis of HF as well as assessing the severity of HF in patients with acute dyspnea so that appropriate and timely treatment can be initiated. 8

This test may also be used to predict the long-term risk of cardiac events or death across the spectrum of acute coronary syndromes when measured in the first few days after an acute coronary event. 9

There is no conclusive evidence currently to warrant the repeated or serial use of BNP or NT-proBNP to alter or monitor treatment of HF especially in hospital inpatients. 16 Therefore, repeated or serial use of BNP or NT-proBNP measurements for monitoring and management of CHF are not a covered service. 17

The measurement of BNP as part of cardiovascular risk assessment panels, consisting of various combinations of biochemical, immunologic, hematologic, and molecular tests, is considered screening when performed on an asymptomatic patient, and, as such, is not a covered Medicare benefit. Please refer to MolDX: Biomarkers in Cardiovascular Risk Assessment L36129 Local Coverage Determination (LCD).

An estimated 92 million United States (US) adults have at least 1 type of cardiovascular disease (CVD) with estimates that over 40% of the US adult population is projected to have some form of CVD by 2030. 5 HF is a multifactorial systemic disease which affects over 26 million people worldwide and is increasing in prevalence. 4 Due to its high morbidity and mortality, the correct diagnosis of HF and cardiac dysfunction is paramount to determine appropriate treatment regimens.

Atrial natriuretic peptide (ANP), BNP and C-type natriuretic peptide (CNP) constitute the human natriuretic peptide family. BNP was originally isolated in pig brain tissue but was also found in the cardiac ventricles and to a lesser extent in the atria. Prior to its activation BNP and NT-proBNP are stored as a 108 amino acid polypeptide precursor proBNP in the ventricles. In response to volume expansion/overload and myocyte stretch, proBNP is cleaved to produce the biologically active 32 amino acid BNP and the 76 amino acid peptide NT-proBNP which are released into the vascular system where they can be detected. 1,2

The strongest indication for BNP measurement is distinguishing between cardiogenic and non-cardiogenic causes of dyspnea in an emergent setting. An elevated BNP level may indicate the need for further cardiac workup to determine the etiology of the patient’s symptoms. 10

A systematic review and meta-analysis of 19 studies involving 22 patient populations with a total of 9093 patients by Battaglia et al. in 2006 11 concluded that the use of BNP tests to rule out HF in different populations ranging from asymptomatic patients in a community setting to patients presenting with acute dyspnea to the emergency department found that negative results accurately rule out the diagnosis of HF especially if patients are at a relatively low risk of HF. B-type natriuretic peptide tests have the potential to guide clinical decisions, particularly in patients at lower risk in primary care and emergency departments. Applied early in the diagnostic process in patients with suspected cardiac failure, negative BNP test findings can help rule out HF and thus, avoid unnecessary referral to echocardiography. If the test result is positive, confirmation by echocardiography will generally be required. Early diagnosis of left ventricular dysfunction or HF can improve the prognosis of patients with left ventricular dysfunction without overt HF and patients with symptomatic HF.