Treatment of inappropriate sinus tachycardia with ivabradine.
BACKGROUND
Inappropriate sinus tachycardia is most often treated with beta-blockers; in resistant cases, nonpharmacologic treatment has been attempted. Recent case reports have shown a favorable response to ivabradine in some patients.


METHODS
A total of 13 patients (11 women, 2 men) aged from 27 to 66 years (mean 42 +/- 8) and having inappropriate sinus tachycardia were treated with ivabradine 15 mg per day.


RESULTS
In 12 patients whose previous therapy could be discontinued or who did not have previous medication the mean daily heart rate decreased from 94.0 +/- 10.0 to 74.6 +/- 5.2 bpm (mean +/- SD) after ivabradine treatment. In 10 patients in whom we could reliably measure the highest and lowest daily heart rates, the highest rate decreased from 150.3 +/- 13.4 to 120.6 +/- 9.8 and the lowest from 66.7 +/- 9.6 to 54.8 +/- 6.9. All of the differences were statistically significant (P < 0.001). The percentage of heart rate reduction correlated with the initial heart rate (P < 0.005). The remaining patient, who had been treated with metoprolol 300 mg per day for more than 10 years and still had a resting heart rate of 106 bpm, switched to 15 mg of ivabradine daily without discontinuation of drug therapy. After this switch, a decrease of 4 bpm was noted in her mean daily heart rate.


CONCLUSIONS
The results of our study show that patients with inappropriate sinus tachycardia can be successfully treated with ivabradine.
Rakovec
Peter
P
Department of Cardiology, University Medical Center, Ljubljana, Slovenia. peter.rakovec@kclj.si
D000328:Adult; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001552:Benzazepines / Q000627:therapeutic use*; D004562:Electrocardiography / Q000187:drug effects*; D005260:Female; D006801:Humans; D000077550:Ivabradine; D008297:Male; D008875:Middle Aged; D013616:Tachycardia, Sinus / Q000175:diagnosis* / Q000188:drug therapy*; D016896:Treatment Outcome
D000889:Anti-Arrhythmia Agents; D001552:Benzazepines; D000077550:Ivabradine