Evaluation of blood cardiac troponin I concentrations obtained with a cage-side analyzer to differentiate cats with cardiac and noncardiac causes of dyspnea

OBJECTIVE: To determine whether measurement of blood cardiac troponin I (cTnI) concentrations with a cage-side analyzer could be used to differentiate cardiac from noncardiac causes of dyspnea in cats. DESIGN: Prospective, multicenter study. ANIMALS: 44 client-owned cats with dyspnea and 37 healthy staff-owned cats. PROCEDURES: Affected cats were examined because of dyspnea; treatment was administered in accordance with the attending clinician's discretion. Cats were judged to have a cardiac or noncardiac cause of dyspnea on the basis of results of physical examination, thoracic radiography, and echocardiography. Blood cTnI concentrations were determined with a cage-side analyzer on samples collected within 12 hours after admission of affected cats. Concentrations for healthy cats were obtained for comparison. RESULTS: 5 enrolled cats were excluded from the study because of concurrent cardiac and respiratory disease. Of the remaining 39 cats with dyspnea, 25 had a cardiac cause and 14 had a noncardiac cause. The 25 cats with a cardiac cause of dyspnea had a significantly higher blood cTnI concentration than did the 37 healthy cats or the 14 cats with a noncardiac cause of dyspnea. CONCLUSIONS AND CLINICAL RELEVANCE: Measurement of cTnI concentrations with a cage-side assay in emergency settings may be useful for differentiating cardiac from noncardiac causes of dyspnea in cats.