Effect of feline characteristics on plasma N‐terminal‐prohormone B‐type natriuretic peptide concentration and comparison of a point‐of‐care test and an ELISA test

BACKGROUND: Increased plasma concentration of N‐terminal‐prohormone B‐type natriuretic peptide (NT‐proBNP) can be detected in cats with cardiac disease. Potential effects of feline characteristics on NT‐proBNP concentration may influence clinical usefulness. OBJECTIVES: To evaluate potential effects of feline characteristics on NT‐proBNP plasma concentration and to compare NT‐proBNP plasma concentrations in healthy cats with results in hypertrophic cardiomyopathy (HCM) cats with or without left atrial enlargement (LAE) using an ELISA and a point‐of‐care test (POCT), and assess if POCT results reflect ELISA results. ANIMALS: One hundred healthy cats of 3 breeds and 39 HCM cats were included. METHODS: Diseases other than HCM were excluded by physical examination, blood pressure measurement, echocardiography, hematology, and serum biochemistry. RESULTS: Higher NT‐proBNP concentrations were found in males than in females in healthy (P = .005) and in HCM cats (P = .0021), but breed had no effect on NT‐proBNP concentrations. Using ≥100 pmol/L as a cutoff for abnormal samples, ELISA and POCT had similar sensitivity (SE; 72 and 74%) and specificity (SP; 97 and 98%) for detecting cats with HCM, cats with HCM and LAE (SE, both 100%; SP, 97 versus 98%), and cats with HCM without LAE (SE, both 69%; SP, 97 versus 98%), respectively, when compared to healthy cats. CONCLUSIONS AND CLINICAL IMPORTANCE: Breed had no effect on plasma NT‐proBNP concentrations, but higher concentrations were found in male than in female cats. The ELISA and POCT had similar SE and SP for detecting HCM. Both tests could identify all HCM cats with LAE but not all HCM cats without LAE.