Evaluation of changes in cardiac biomarker concentrations and enzyme activities in serum after short- and long-duration transcutaneous cardiac pacing in dogs.
OBJECTIVE
To evaluate serum cardiac biomarker concentrations and selected enzyme activities in dogs with experimentally induced bradyarrhythmias after short- (1-hour) and long- (3-hour) duration transcutaneous cardiac pacing (TCP).


METHODS
10 healthy Beagles.


METHODS
In each dog, anesthesia was induced with propofol (5 mg/kg, IV) and maintained via inhalation of isoflurane in oxygen. To induce bradyarrhythmia, diltiazem was administered IV (20 to 50 mg/dog). Transcutaneous cardiac pacing was performed for 1 hour (5 dogs) or 3 hours (5 dogs) by use of an automated external cardiac pulse generator and a transdermal electrode. Serum concentrations of creatine kinase-MB fraction and cardiac troponin I and activities of aspartate transaminase, creatine kinase, and lactate dehydrogenase were evaluated the day before (baseline) and at intervals until 7 days after TCP.


RESULTS
Increases (from baseline) in serum cardiac biomarker concentrations and enzyme activities were detected in the long-duration TCP group; changes in the short-duration TCP group were more minor and largely not significant. Although severity of myocardial and skeletal muscular injuries was apparently greater with greater duration of TCP, the injuries were not persistent; most variables were within reference range within 3 days after TCP.


CONCLUSIONS
Results indicated that application of TCP for > 1 hour in dogs may cause myocardial and skeletal muscular injuries. Serum concentrations of creatine kinase-MB fraction and cardiac troponin I and activities of aspartate transaminase, creatine kinase, and lactate dehydrogenase should be more carefully monitored after TCP of > 1 hour's duration to evaluate potential myocardial damages.
Lee
Seungkeun
S
Korea Animal Hospital, 574-10 Sajik-dong, Cheongju 361-101, Republic of Korea.
Pak
Son-Il
SI
Hyun
Changbaig
C
D000818:Animals; D015415:Biomarkers / Q000097:blood; D002304:Cardiac Pacing, Artificial / Q000662:veterinary*; D052279:Creatine Kinase, MB Form / Q000097:blood; D004285:Dogs / Q000097:blood / Q000502:physiology*; D004798:Enzymes / Q000097:blood*; D005260:Female; D006321:Heart / Q000503:physiopathology*; D008297:Male; D009206:Myocardium / Q000201:enzymology*; D013997:Time Factors; D004561:Transcutaneous Electric Nerve Stimulation / Q000662:veterinary; D019210:Troponin I / Q000097:blood*
D015415:Biomarkers; D004798:Enzymes; D019210:Troponin I; D052279:Creatine Kinase, MB Form