Abstract
The use of cardiac troponin (cTn), the 'gold-standard' biomarker of myocardial injury in humans, is growing in veterinary medicine and in animal safety studies, although there are differences in its application in animals. In this study six new assays for the marker were assessed in 619 animals of six different species (dog, cat, horse, cattle, rat and rabbit), in clinical and drug-safety studies. Healthy animals and clinical cases without cardiac disease served as controls. Several of the tested assays had poor analytic or diagnostic sensitivity and only one test was effective in all species and in all models of cardiac injury. This assay had the highest sensitivity and widest dynamic range, and identified cardiac injury due to anaemia, pancreatitis, uncontrolled Addison's and Cushing's disease, old age, renal disease, severe colic, lymphoma and neoplasia. Detection of the cTnI and cTnT forms correlated with loss of cardiac function in toxicity studies in rodents and rabbit. Increased serum cTnI was not found to correlate with disease aetiology or pathogenesis, but was effective in detecting, monitoring and quantifying ongoing cardiac injury. Cardiac injury, as demonstrated by elevated cTnI in blood, appears to be a common sequel to a wide variety of both primarily cardiac disease and of other diseases that do not primarily involve the cardiovascular system.