Two important endocrine (hormone) systems regulate our cardiovascular function, the Renin-Angiotensin System and the Natriuretic Peptide System. They work in opposite ways and particularly help in blood pressure regulation. Over-activation of these systems, which can happen in cardiomyopathy, leads to heart failure symptoms. Common cardiac drugs work to restrict these systems.
Natriuretic peptides (NP) are hormones that are released in response to distension (stretch) or inflammation.
Three types of NP can relate to the heart, ANP, BNP and CNP:
- Atrial natriuretic peptide (ANP) is released in response to atrial stretch
- B-type or brain natriuretic peptide (BNP) is released in response to ventricular stretch
- C-type natriuretic peptide (BNP) is released by the vascular system when there is inflammation
The release of NPs causes dilation or relaxation of the heart muscle and vessels, excretion of fluid and sodium (natriuresis diuresis) which in turn drops blood pressure. They can also inhibit fibrosis.
Why are BNP levels important?
Levels of BNP are checked in your blood. The higher the level, the greater the indicator of heart distension or overload. It is commonly used to rule out or assist in identifying heart failure. It is usual for people with cardiomyopathy to have elevated BNP levels. Normal levels are generally considered to be anything under 100pg/ml but please note units of measurement can differ.
What about NT-proBNP?
NT-Pro BNP is an inactive hormone, released at the same time as BNP. It considered to be a more accurate measurement of BNP levels in your blood. Normal NT-Pro BNP levels are generally considered to be anything under 400pg/ml
All values should only be compared to your baseline reading. BNP and NT-proBNP values should not be compared.
Speak to a nurse
You can call our specialist nurse helpline on 0800 018 1024, the lines are open Monday to Friday, from 8:30am - 4:30pm. You can also email supportnurse@cardiomyopathy.org or open a live chat here on our website.