Information About Brain Natriuretic Peptide Test

Submitted on March 27, 2012

Our heart produces a hormone called as BNP or the Brain Natriuretic Peptide. The BNP is also called as the B-Type Natriuretic Peptide. The ventricles of your heart release BNP when the heart muscle cells are excessively stretched.

Measuring the level of BNP in the blood can help to identify potential heart failure. High levels of BNP in the blood indicate that the heart has been working harder than normal over an extended period.


Doctors prescribe a BNP and NT-proBNP test when they want to identify a potential heart failure, assess the severity of an existing failure, or to measure the response to a heart failure related treatment.

Patients with edema and symptoms such as shortness of breath, difficulty in breathing, and fatigue are put through the BNP test along with an echocardiogram. This helps a doctor to identify if the symptoms are related to a heart failure or lung disease, helping them derive the next course of action.

There is some amount of preparation that is required before appearing for a BNP test. For the results to be accurate, you are required not to eat any food or drink anything but water for the preceding 8 to 12 hours. A blood sample is collected from the veins to conduct the tests.

The amount of BNP in your blood is measured as pg/mL or 'picograms per milliliter'.

Measuring The Values of Brain Natriuretic Peptide or BNP Test

A reading of 0-99 pg/mL is considered normal.

Any reading from 100 - 900 pg/mL is considered abnormal and can indicate heart failure at varying levels of severity. You may use the following reference to interpret the readings:

  • 100-300 pg/mL is an indication of a potential heart failure.
  • 300 pg/mL or higher is an indication of mild heart failure.
  • 600 pg/mL or higher is an indication of moderate heart failure.
  • 900 pg/mL or higher is critical and is considered as severe heart failure.

Higher BNP values can indicate an abnormal functioning of the heart and can be due to a high amount of fluid in the heart. It may also be due to high pressure in the heart.

Higher values indicate greater chances of death, especially in people with heart diseases and also indicate the onset of heart failure in people who are undergoing kidney dialysis.

Your doctor will repeat the BNP test after putting you on medication to see the effect of treatment. As the medication progresses the BNP level can come down indicating that the treatment was effective.

It is important to note that the BNP value varies with age, however will always remain within the normal value of there are no symptoms of heart failure.