Test Code

Alias/See Also
NT-Pro B-Type Natriuretic Peptide

CPT Codes

Preferred Specimen

EDTA Plasma (Purple Top Tube)

Minimum Volume
1.0 mL

Other Acceptable Specimens
Serum (gold top tube) or Lithium Heparin Plasma (green top tube)

Transport Container

EDTA Plasma (purple top), Serum (gold top), or Lithium Heparin Plasma (green top) tube

Transport Temperature
Room Temperature or Refrigeration

Specimen Stability
Room Temperature - 3 days; Refrigerated - 3 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Hemolysis, Turbidity, Quantity Not Sufficient, IV contamination


Setup Schedule

Daily upon receipt

Report Available
Upon completion of analysis

Serum concentrations of natriuretic peptides may be elevated in patients with acute myocardial infarction and renal insufficiency. Factors such as these should be considered when interpreting results from any NT-proBNP or BNP method. k of NT-Pro BNP elevations have been reported if congestive heart failure is very acute (first hour) or occurs with ventricular inflow obstruction (hypertrophic obstructive cardiomyopathy, mitral stenosis, atrial myxoma).

Reference Range

Birth - 75 Years Old:     0 - 125 pg/mL
Older than 75 Years:    0 - 450 pg/mL

Clinical Significance

B-type natriuretic peptide (brain natriuretic peptide: BNP) is a small, ringed peptide secreted by the heart to regulate blood pressure and fluid balance.  This peptide is stored in and secreted predominantly from membrane granules in the heart ventricles in a pro form (Pro BNP). Once released from the heart in response to ventricle volume expansion and/or pressure overload, the N-terminal (NT) piece of 76 amino acids (NT-Pro BNP) is rapidly cleaved by the enzymes corin and/or furin to release the active 32 amino acid peptide (BNP).

Both BNP and NT-Pro BNP are markers of atrial and ventricular distension due to increased intracardiac pressure.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.