Cardiac troponin I in the normal dog and cat

Cardiac troponin I (cTnI) has proven to be a highly specific and sensitive marker for myocardial cellular damage in many mammalian species. The struct ure of cTnI is highly conserved across species, and assays for human cTnI ( including the one used in the current study) have been validated in the dog . Blood concentrations of cTnI rise rapidly after cardiomyocyte damage, and assay of cTnI potentially may be valuable in many clinical diseases. The p urpose of this study was to establish the normal range of cTnI in hepariniz ed plasma of dogs and cats. Forty one clinically normal dogs and 21 cats we re included in the study. One to 3 milliliters of blood were collected by v enipuncture into lithium heparin vacutainers for analysis of cTnI (Stratus( (R)) CS). The range of plasma cTnI concentrations in dogs was <0.03 to 0.07 ng/mL with a mean of 0.02 ng/mL, with the upper tolerance limit (0.07 ng/m L) at the 90th percentile with 95% confidence. In cats, the range was <0.03 to 0.16 ng/mL with a mean of 0.04 ng/mL, and the upper tolerance limit (0. 16 ng/mL) at the 90th percentile as well with 90% confidence. This study es tablishes preliminary normal ranges of plasma cTnI in normal dogs and cats for comparison to dogs and cats with myocardial injury or disease.