Treatment of inappropriate sinus tachycardia with ivabradine

Inappropriate sinus tachycardia (IST) often causes palpitations, dyspnea, and exercise intolerance, that are generally treated with beta blockers and non-dihydropyridine calcium-channel antagonists. Ivabradine, a selective inhibitor of cardiac pacemaker I-f current, has recently emerged as an effective and safe alternative to conventional drugs for IST.We performed a systematic overview of clinical studies on the therapeutic yield of ivabradine in patients with inappropriate sinus tachycardia, published in MEDLINE database from January 2000 to March 2015.Overall, five case reports were found, all showing efficacy of ivabradine in subjects affected by IST. Eight non-randomized clinical studies demonstrated short- and medium-term safety and efficacy of ivabradine administration in IST, also in adjunction to or in comparison with metoprolol. One double-blind randomized crossover study also showed that ivabradine is superior to placebo for heart rate (HR) reduction and symptoms control in patients affected by IST.Ivabradine is effective and safe in short- and medium-term treatment of IST. However, long-term follow-up studies and randomized studies comparing ivabradine with beta blockers are still lacking.