The NT-proB-type natriuretic peptide (BNP) blood test is a test that helps a healthcare specialist determine whether or not you have heart failure by measuring the levels of two hormones in your blood. The hormone B-type natriuretic peptide (BNP) is made by the heart, while the N-terminal (NT)-pro hormone BNP (NT-proBNP) is a non-active prohormone that’s released from the same molecule that makes BNP.
Both BNP and NT-proBNP are released by our bodies in response to pressure changes that occur inside our hearts; they can be in response to a number of heart-related conditions, which include cardiac failure. Levels of BNP and NT-proBNP rise when heart failure develops or worsens, and decrease when heart failure stabilizes. BNP and NT-proBNP are most often higher in patients who have heart failure than those who have a normally-functioning heart.
Healthcare providers measure both BNP and NT-proBNP levels using a blood test; this will help them diagnose and track heart failure. For instance, if you’re experiencing shortness of breath or fatigue with increasing severity, your doctor may order a blood panel and check your levels of BNP and NT-proBNP to see if these symptoms are due to heart failure or another issue.
The Cleveland Clinic’s reference ranges for normal levels of NT-proBNP are:
- Less than 125 pg/mL for patients between 0-74
- Less than 450 pg/mL for patients between 75-99
The Cleveland Clinic says the following levels of NT-proBNP could mean you’re experiencing unstable heart function:
- Higher than 450 pg/Ml for patients under 50
- Higher than 900 pg/Ml for patients 50 and above
This test, however, is only one method of many to monitor any particular condition.