Specific cardiac biomarkers play a crucial role in the identification of cardiac disturbances. A biomarker can be objectively measured and evaluated as an indicator of normal or pathological biological processes. Some common biomarkers include pulse and blood pressure, basic chemistry, and more complex laboratory tests using blood and tissue samples. Cardiac biomarkers can provide rapid and accurate information on myocardial necrosis/cell injury and hemodynamic stress. The most studied cardiac biomarkers in veterinary medicine include the N-terminal fragment pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin I.
B-type natriuretic peptide
B-type natriuretic peptide (BNP) is a hormone produced and secreted by heart muscle cells (cardiomyocytes) in response to excessive cell stretch. BNP helps regulate intravascular volume homeostasis and systemic pressure and counteracts the renin-angiotensin-aldosterone effects. (RAAS), which is upregulated with heart disease. Canine NT-proBNP promotes sodium and water loss through the kidneys and vasodilation, both of which help decrease cardiac stretch and work. Many heart diseases cause excessive stretching of cardiomyocytes and increased release of BNP. The magnitude of the increase in the level of circulating BNP has been correlated with the severity of the cardiac disease.
Cardiomyocytes secrete BNP as a precursor prohormone. The prohormone is divided into 2 fragments: a bioactive C-terminal fragment (C-BNP) and an inactive NT-proBNP fragment. C-BNP has a short half-life (approximately 90 seconds) which limits the ability to measure. NT-proBNP has a longer half-life (approximately 120 minutes) and has improved stability during sample handling, making it into an ideal biomarker.
NT-proBNP tests
NT-proBNP levels are measured in serum and testing can be done in external laboratories or with clinical trials. A newly released assay by Bionote’s veterinary team is the first of its kind for veterinarians to provide a quantitative measurement of NT-proBNP level in the clinic within minutes. Adding quantitative NT-proBNP test results to examination findings can help identify dogs with advanced heart disease that would benefit from additional diagnostics and can help monitor dogs with known heart disease.
The canine NT-proBNP test for Bionote is available under their Vcheck brand line of tests and analyzers. It is the first and only quantitative NT-proBNP in the clinic for the detection of heart disease. It should be noted that other BNP tests on the market must be sent to reference laboratories for confirmation, which takes more time and incurs a higher risk of sample degradation affecting precision. Although no specific test finding or result is adequate or appropriate to diagnose heart disease, when many pieces of information are combined, a stronger cardiac clinical picture develops.