Analysis of cardiac troponin I is considered the “gold standard “ for the non-invasive diagnosis of myocardial injury in people and small animals. It has replaced traditionally used cardiac biomarkers such as creatine-kinase and its isoenzymes due to its high sensitivity and specificity for the detection of myocardial injury. In cattle the diagnosis of myocardial disease has been made on the basis of physical exam, radiography in cases of traumatic reticulo-pericarditis, electrocardiography and echocardiography.
The purposes of this study were to evaluate a commercially available immunoassay for the detection of bovine cTnI and to show that cTnI will increase in cattle with myocardial injury. We hypothesized that a commercially available immunoassay is highly sensitive and specific for the detection of bovine cTnI and that increased serum concentrations of cTnI are associated with myocardial necrosis in cattle.
The study was divided into two parts. The first part of the study validated a commercially available immunoassay for the detection of bovine cTnI. Serum of 30 healthy dairy cows was analyzed for cTnI and a reverence range was established.
The second part of the study evaluated the relationship of cTnI concentration and electro- and echocardiographic and histopathologic findings after an administration of an overdose of monensin in 10 cows.
We demonstrated that the ADVIA Centaur immunoassay can reliably be used for the detection of cTnI in cattle and that an increased cTnI of ≥ 1.04 ng/ml was highly specific for the presence of myocardial necrosis. Furthermore, an association between cTnI and left ventricular dysfunction was documented.
Further studies are needed to evaluate the diagnostic benefit of cTnI analysis in cattle with naturally occurring heart disease.