¹Istanbul University Cerrahpasa, Faculty of Veterinary Medicine, Department of Internal Medicine, TR-34320 Istanbul - TURKEY DOI : 10.9775/kvfd.2020.25073 Feline arterial thromboembolism (FATE) is a common complication of myocardial disease, often having poor prognosis. The purpose of this study is to evaluate the diagnostic and prognostic value of serum levels of cardiac biomarkers (N-terminal prohormone of brain natriuretic peptide [NT- proBNP], creatine kinase isoenzyme-MB [CK-MB], and cardiac troponins [cTnI and cTnT] in cats with hypertrophic cardiomyopathy (HCM) that was complicated by FATE. Two groups were constituted in the study. Cats with a diagnosis of HCM were included in group I (n=10) and cats with HCM having acute episodes of FATE were included in group II (n=10). Results of cardiac biomarkers and echocardiographic measurements of left ventricle related parameters were compared between groups. The ratio of left atrium to aorta (P<0.05), fractional shortening (P<0.05), left ventricular dimensions (P<0.05), and stroke volume (P<0.01) were found statistically significant between groups. Serum CK-MB and cTnI levels in group II were higher (P<0.001 and P<0.05 respectively)) than those in group I. Serum levels of cTnI and cTnT were found respectively under 3.0 ng/mL and 0.1 ng/mL in the cats (n=3) which have survived. Our data demonstrate that remarkably elevated serum levels of cardiac biomarkers could be associated with the diagnosis of HCM with acute onset of FATE in cats, however cTnI and CK_MB might have a role in the risk assessment. Keywords : Cardiac troponins, CK-MB, Feline arterial thromboembolism, Hypertrophic cardiomyopathy, NT-proBNP