Serum Levels of Creatine Kinase Isoenzyme MB and Cardiac Troponin I (CTnI) in Dogs with Normal Electrocardiogram and in those with ST Segment Deviation Using Chemiluminescence Assay
As opposed to men, hypoxic/ischemic heart diseases are seldom related in dogs. Acute myocardial infarct is rare in this species. However, there are some electrocardiographic findings which point to myocardial ischemia or hypoxia, as the ST segment deviation (elevation or depression).
Thirty-eight adult dogs, males or females, were evaluated. From these dogs, 20 shown normal electrocardiogram (group I) and 18 shown ST segment deviation (group II). The CK MB and cTnI serum level of healthy dogs were used as pattern of normal values, which were compared to those obtained from dogs that had ST segment deviation. The serum levels of CKMB and cTnI allowed to assure or not the myocardial damage. The group I shown a CKMB mean value of 0,54 ng/ml, with standard deviation of 0,89 mg/ml. The mean value of cTnI in these dogs was 0,16 ng/ml, with standard deviation of 0,110 ng/ ml. The group II shown CK MB mean value equal to 0,44 ng/ml, with standard deviation of 1,106 ng/ml. These dogs had a mean value of cTnI of 0,20 ng/ml, and standard deviation of 0,111 ng/ml. The serum level of CK MB and cTnI were severely affected by age. So, the group I were composed mainly by dogs younger than 7 years old, while just the opposite occurred in group II. Association between CKMB x age, CKMB x body mass and CKMB x CKT were significant (p<0,05) in group I. In group II the association CKMB x CKT were significant. CKMB and cTnI were not statistically different in group I and II (p<0,05).
So, it can be concluded that the human kit of chemiluminescence assay can be used to measure CKMB and cTnI level in dogs. Also, the hypoxia or ischemia, revealed by electrocardiographic abnormalities (ST segment deviation) is not related to myocardial cell damage.
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