NT-proBNP
Also called: BNP, N-terminal pro B-type natriuretic peptide
Cardiac neurohormone released by ventricular wall stretch. Elevated in heart failure and cardiac stress — the rule-out test for shortness of breath of unclear origin.
Published: Updated:
Check your result
Calculated in your browser - the number is not sent anywhere.
Have the whole report? Upload it - we'll explain every value on it
What does NT-proBNP measure?
When the heart's ventricles are stretched — by volume overload, pressure overload, or weakened pumping — they release a precursor protein that is cleaved into active BNP and inactive NT-proBNP. NT-proBNP has a longer half-life and is the more commonly measured form. The test is most useful for ruling OUT heart failure: a value below 125 pg/mL in patients younger than 75 (or below 450 pg/mL in older patients) makes heart failure unlikely. Elevated values widen the differential — heart failure is the dominant cause but pulmonary embolism, renal failure, sepsis, and atrial fibrillation can also raise NT-proBNP.
What does a high NT-proBNP level mean?
- Heart failure — the primary diagnostic application; degree of elevation correlates with severity.
- Atrial fibrillation — elevates NT-proBNP even without heart failure.
- Pulmonary embolism — right ventricular strain.
- Chronic kidney disease — reduced clearance.
- Sepsis, critical illness — cardiac response to systemic stress.
- Older age — values rise with age physiologically.
What does a low NT-proBNP level mean?
- Heart failure unlikely — the most clinically useful finding.
- Obesity — paradoxically lowers NT-proBNP; can mask early heart failure.
When to discuss with a doctor
NT-proBNP is most useful for ruling out heart failure in patients with shortness of breath. Elevated values in a patient with new dyspnoea warrant prompt echocardiogram and clinical evaluation. Mediora.AI doesn't interpret NT-proBNP in isolation; it's a clinician's tool in the diagnostic pathway.