Cor Vasa 2007, 49(9):323-325

Bradines - a novel approach to the management of myocardial ischemia

Jan Bultas

Ústav farmakologie, 3. lékařská fakulta Univerzity Karlovy, Praha, Česká republika

Heart rate is an important factor affecting, in patients with coronary atherosclerosis, perfusion by the left ventricle and the incidence of myocardial ischemia. Heart rate lowering has been used to reduce the ischemic burden since the 1960s with the advent of beta-blockers. An alternative approach resulting in heart rate reduction is inhibition of the specific If ion current in the sinus node. Selective If inhibition by ivabradine, the first representative of a newly formed class referred to as sinus node inhibitors or bradines, is a major addition to the spectrum of drugs available for the management of angina.
The mode of action of ivabradine consists in inhibiting the spontaneous depolarization of sinus node cells by blocking the If potassium channel and slowing spontaneous pacemaker cell depolarization. The result is purely negative chronotropic activity devoid of an effect on the velocity of impulse conduction and contractility.
The effect of ivabradine on improving exercise tolerance and reducing the incidence of ischemia has been confirmed in monotherapy and in combination with vasodilators, and was comparable with that of beta-blockers and calcium-channel blockers. However, unlike beta-blockers, ivabradine use has not been associated with negative inotropic and negative dromotropic activity, no adverse metabolic effects have been reported, and no bronchoconstriction develops. The only major side effect of ivabradine is visual sensations characterized as flashes or brightness in the visual field periphery after a change in lighting conditions.
Ivabradine is indicated as an alternative to beta-blockers for the symptomatic management of angina, and is used with advantage in cases where beta-blockers are contraindicated. In this indication, ivabradine has been put on the list of drugs currently reimbursed by health insurance companies.

Keywords: Bradines; Ivabradine; Angina; Myocardial ischemia; If inhibition

Published: September 1, 2007  Show citation