Journal of Young Pharmacists

LETTER TO EDITOR
Year
: 2009  |  Volume : 1  |  Issue : 3  |  Page : 284-

Ivabradine: Novel if channel inhibitor


H Ameya1, A Kumar2,  
1 Faculty of Medicine, AIMST University, Malaysia
2 Unit of Pharmacology, Faculty of Medicine, Malaysia

Correspondence Address:
H Ameya
Faculty of Medicine, AIMST University
Malaysia




How to cite this article:
Ameya H, Kumar A. Ivabradine: Novel if channel inhibitor.J Young Pharmacists 2009;1:284-284


How to cite this URL:
Ameya H, Kumar A. Ivabradine: Novel if channel inhibitor. J Young Pharmacists [serial online] 2009 [cited 2014 Apr 16 ];1:284-284
Available from: http://www.jyoungpharm.in/text.asp?2009/1/3/284/57073


Full Text

Pacemaker activity of the heart involves interplay between several ionic currents that influence spontaneous diastolic depolarization of the sinoatrial node, including I f current. The search for pure heart rate-lowering agents to prevent angina without over all adverse effects of β-blockers[1] began more than three decades ago. The discovery of I f current and I f channels offered a possible approach to the developing pure heart rate-lowering agents. [1]

Ivabradine is a selective I f channel blocker drug which can be used in the treatment of angina. Ivabradine causes bradycardia without any negative inotropic effects. It causes an immediate increase in coronary blood flow due to an increase in the diastolic time interval during which blood flows to the myocardium. Ivabradine reduces myocardial oxygen demand, improves exercise capacity and preserves ventricular contractility. Further Ivabradine does not change any major electrophysiological parameters unrelated to heart rate. 'Pure' heart-rate lowering via I f inhibition effectively prevents angina with acceptable tolerability. [1]

Ivabradine effectively prevents angina and concomitantly reduces ischemia. Ivabradine 5 mg and 7.5 mg twice daily (bid) are the licensed dosages for the treatment of stable angina. [1],[2]

About 14.5% of all patients taking the drug experience 'luminous phenomena' (sensations of enhanced brightness in a fully maintained visual field). This is probably due to blockage of Ih ion channels in the retina which are very similar to cardiac If. These symptoms are mild, transient and fully reversible. Bradycardia occurs in two per cent of the patients. Headaches, AV block, ventricular extrasystoles and dizziness are also associated with the use of Ivabradine.[1]

Ivabradine is contraindicated in severe bradycardia, moderate to severe heart failure, severe hypotension, second and third degree heart blocks. Its use is not recommended in cardiac arrhythmias that interfere with sinus node function. [1]

Ivabradine is indicated for chronic stable angina in sinus rhythm patients who have a contraindication or intolerance to beta blockers and a high resting heart rate. [2],[3]

References

1Sulfi S, Timmis AD. Ivabradine-the first selective sinus node If channel inhibitor in the treatment of stable angina. Int J Clin Pract 2006;60:222-8.
2Tardif JC, Ford I, Tendera M, Bourassa MG, Fox K. Efficacy of ivabradine: A new selective I (f) inhibitor, compared with atenolol in patients with chronic stable angina. Eur Heart J 2005;26:2529-36.
3Anonymous. New medicines: Procoralan. Pharmaceutical Journal 2006;276:131.