Assessment of amiodarone effects on intact cats' electrocardiograms

Amiodarone can be used for treatment of ventricular and supraventricular arrhythmias in canine medicine, but its exact role in feline electrocardiography and its side effects have not been proven. The aim of this study was the evaluation of amiodarone and its different dosages effects on intact feline heart electrocardiograms. Eight healthy stray cats were selected and control electrocardiogram was obtained. Amiodarone tablets were prescribed twice daily at 10 mg/kg for 7 days. The same protocol was repeated with doses of 15 and 25 mg/kg. Hexagonal electrocardiograms were obtained at the end of each stage. Electrocardiograms were evaluated for P amplitude and duration, QRS duration, R amplitude, QT interval, PR interval, and heart rate changes. All data were compared with the control and between groups electrocardiograms. Obvious changes were seen in PR interval, QT interval, and heart rates in all dosages but P duration changes were seen only with the 25 mg/kg dosage. We used the same doses that were recommended in canine medicine. This study showed that 10 mg/kg of amiodarone has no visible changes in cats electrocardiograms, but a toxic dose and even the dose of 15 mg/kg produced some obvious changes. Therefore, more studies are necessary to find the proper amiodarone doses in cats.

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