查看文章

Purpose: We aimed to assess the effect of chronic ivabradine administration on atrial arrhythmogenesis in in vivo, healthy rats.

Methods: Healthy male Wistar rats were randomized into two groups: Control (n= 13) and treated with ivabradine (IVA; n= 15). Ivabradine (10 mg/kg/day) was administered in the drinking water for three consecutive weeks. All rats were implanted with radiotelemetry ECG devices. Nine control and five IVA rats were then submitted to transesophageal pacing (4000 stimuli/min for 20 s; 15 cycles) for 5 consecutive days. First day and overall arrhythmia inducibility was assessed. 72-h continuous ECG monitoring was performed in freely moving rats before and after the stimulation protocols, and the number and duration of spontaneous atrial tachyarrhythmia episodes were determined.

Results: Rats in the IVA group presented significantly lower heart rates both before (299±27 vs. 354±51 bpm, p< …