Cardiac troponin I: evaluation of a biomarker for the diagnosis of heart disease in the dog



Objectives: To assess the value of measuring blood levels of the myocardial protein cardiac troponin I (cTnI) in the diagnosis of congenital and acquired heart disease in the dog and in the evaluation of the severity of heart failure.

Methods: Serum samples obtained from healthy dogs (n=26) and from dogs diagnosed with a variety of congenital and acquired heart conditions (n=35) were assayed for cTnI concentration using an automated immunoassay method. Results were also analysed according to the degree of heart failure as assessed using the International Small Animal Cardiac Health Council's scheme.

Results: Healthy dogs had very low or undetectable blood cTnI levels, as did dogs with congenital heart disease. However, cTnI levels were significantly elevated in dogs with acquired mitral valve disease, dilated cardiomyopathy and pericardial effusion. Blood cTnI levels also varied with severity of heart failure.

Clinical Significance: Measurement of blood cTnI levels may be a useful aid in the diagnosis of dogs with suspected heart disease and in indicating the severity of heart failure.