Cardiac Troponin I and Amino‐Terminal Pro B‐Type Natriuretic Peptide in Dogs With Stable Chronic Kidney Disease

BACKGROUND: Increased concentrations of N‐terminal pro B‐type natriuretic peptide (NT‐proBNP) and cardiac troponin I (cTnI) in dogs with azotemia have been documented. Knowledge of mechanisms behind increased concentrations of cardiac biomarkers in dogs with azotemia is warranted for correct interpretation of test results. OBJECTIVES: The aim of the article was to investigate possible associations between plasma concentrations of cTnI and NT‐proBNP, respectively, and patient characteristics, glomerular filtration rate (GFR), a plasma volume factor (PVF) derived from scintigraphic examination (PVf), systolic blood pressure (SBP), selected hematologic and biochemical variables, and echocardiographic measurements in dogs with stable chronic kidney disease (CKD) and in healthy dogs. ANIMALS: Fifty student‐, staff‐, and client‐owned dogs were included. Twenty‐three of the dogs were healthy and 27 were diagnosed with CKD. METHODS: In this cross‐sectional observational study, dogs with a previous diagnosis of CKD and healthy control dogs were included. At inclusion, all dogs were characterized by physical examination, repeated blood pressure measurements, complete urinalysis, hematology and biochemistry panel, echocardiography, abdominal ultrasound examination of the entire urinary tract, and scintigraphic examination for measurement of GFR. RESULTS: Plasma volume factor and PCV were independently associated with NT‐proBNP ([Formula: see text] = 0.42; P < .0001). Age, body weight (BW), and SBP were independently associated with cTnI ([Formula: see text] = 0.50; P < .0001). CONCLUSIONS AND CLINICAL IMPORTANCE: Neither NT‐proBNP nor cTnI concentrations were independently associated with measured GFR. Thus, findings were not suggestive of passive accumulation of either marker, suggesting that increased circulating concentrations of cTnI and NT‐proBNP can be interpreted similarly in dogs with stable CKD as in dogs without CKD.