Arrhythmic effects of Ivabradine in patients with coronary artery disease

Objectives: Ivabradine is the first specific heart ratelowering agent that has completed clinical development for stable angina pectoris. The aim of the present study was to investigate the effects of ivabradine therapy on P-wave duration, dispersion and QT duration, dispersion in coronary artery disease patients. Methods and Results: The study population consisted of 21 patients with CAD who have confirmed by coronary angiography previously. Written informed consent was obtained in all patients. Twelve-lead electrocardiogram was recorded for each subject at a rate of 50mm/s on admission and repeated after 1 month ivabradine therapy. QT duration, QT dispertion, maximum and minimum QT duration calculated. Maximum and minimum P wave and P wave dispersion has been calculated. Heart rate was decreased after ivabradine therapy. (75 +/- 15 and 63 +/- 10, P=0.02). There was no difference between Pmax, Pmin and Pdis values before and after treatment. QTmax value was prolonged after treatment. (410 +/- 43 and 431 +/- 14, P=0,005) but there was no difference between cQTmax value.(455 +/- 38 and 439 +/- 21) There was no difference between QTdis and cQTdis values before and after treatment. (44 +/- 18 & 49 +/- 14; and 49 +/- 22 & 48 +/- 15). QTmax was prolonged after ivabradine therapy but cQTmax, Pdis, QTdis and cQTdis were not prolonged. Conclusion: There is no relationship between ivabradine therapy and increased risk of ventricular and atrial arrhythmia in coronary artery disease patient.