Question: What is a BNP blood test, and should it be done on everyone with heart failure?
Answer: A B-Type natriuretic peptide is a naturally-occurring peptide produced by the body. A peptide is a group of amino acids, the building blocks of proteins, and this particular peptide is secreted in response to certain stress; this one in particular is the stress in the heart, particularly when the heart is stretched.
One of the hallmarks of heart failure is when people hold on to too much fluid. When they hold on to too much fluid it begins to backup and literally stretch the heart. That extra stretch causes the cells of the heart to excrete BNP and that can be measured in the blood.
And the higher the BNP generally the more fluid someone maybe holding on to, although it does vary a little bit from person to person. But that why it can be useful in the setting of somebody being short of breath to distinguish whether the shortness of breath is due to fluid being held on because of heart failure or whether it's due to lung disease.
Should everybody have one? It can be use full from a prognosis stand point how well is a given person is going to do over the long run. People who have a very high BNP, In general don't do as well as people who have a low BNP or normal BNB that's not necessarily universal there are other things that can affect BNP such as age, gender, women tend to have higher BNP then men, as well as things such as kidney disease.
People with kidney disease tend to have higher BNP that people who do not it's a good marker it has to be taken in full context of a given patient.