Ivabradine: the evidence of its therapeutic impact in angina

Ranolazine and Ivabradine: two different modalities to act against ischemic heart disease

Among the innovative drugs recently introduced for the management of chronic stable angina, Ranolazine and ivabradine represent two most true innovations. In fact, even if both drugs act by reducing myocardial work and thus oxygen consumption, this happens by a peculiar mechanism unlike that of conventional antischemic drugs. Ranolazine mediates its antianginal effects by the inhibition of cardiac late sodium current. This improves myocardial relaxation favoring myocardial perfusion. Ivabradine is a selective If channel blocker and acts by reducing firing rate of pacemaker cells in the sinoatrial node, without affecting the duration of action potential. The reduction of heart rate causes a reduction of left ventricular end diastolic pressure and increases the time useful to coronary flow by a prolongation of the diastole. A body of evidence found that two drugs are useful in ischemic patients whether at rest or during exercise. In addition, they can be used in monotherapy or in association with other conventional anti-ischemic drugs. The two medications could be used with advantage also in microvascular angina when standard therapy is ineffective. Thus, the two drugs represent an adjunctive and powerful therapeutic modality for the treatment of chronic stable angina, especially when conventional antianginal drugs were insufficient or inadequate.

Ivabradine, coronary artery disease, and heart failure: beyond rhythm control

Elevated heart rate could negatively influence cardiovascular risk in the general population. It can induce and promote the atherosclerotic process by means of several mechanisms involving endothelial shear stress and biochemical activities. Furthermore, elevated heart rate can directly increase heart ischemic conditions because of its skill in unbalancing demand/supply of oxygen and decreasing the diastolic period. Thus, many pharmacological treatments have been proposed in order to reduce heart rate and ameliorate the cardiovascular risk profile of individuals, especially those suffering from coronary artery diseases (CAD) and chronic heart failure (CHF). Ivabradine is the first pure heart rate reductive drug approved and currently used in humans, created in order to selectively reduce sinus node function and to overcome the many side effects of similar pharmacological tools (ie, β-blockers or calcium channel antagonists). The aim of our review is to evaluate the role and the safety of this molecule on CAD and CHF therapeutic strategies.

Comparison of the efficacy and tolerability of ivabradine and ranolazine in patients of chronic stable angina pectoris

Introduction:

To compare the efficacy and tolerability of Ivabradine (IVA) and Ranolazine (RAN) in chronic angina patients.

Materials and Methods:

This was a follow-on, open-label trial conducted in a tertiary care hospital of Uttarakhand. Thirty patients each taking IVA 5 mg twice daily or RAN 500 mg twice daily were distributed to the respective groups. Patients were asked to fill a pretested questionnaire on frequency of anginal attacks and adverse reactions before and 2, 4 and 8 weeks after taking the respective medicines. Their blood pressure, heart rate and routine hematological and biochemical estimations were performed at baseline and after intervention. Results were statistically analyzed using different statistical tests, with P < 0.05 considered as significant.

Results:

There was no significant difference in the frequency of anginal attacks per week between the groups. The adverse drug reactions (ADRs) reported in the IVA group were dizziness (30%), headache (16.6%), backache (16.6%), vertigo (13.3%), blurred vision (13.3%), muscle cramps (10%), arthralgia (10%), cough and dyspnea (6.6%), hypersensitivity rash (6.6%), fever (3.3%) and nausea (3.3%). The ADRs in the RAN group were nausea (26.6%), dizziness (23.3%), vomiting (3.3%), constipation (3.3%) and vertigo (3.3%). The blood pressure, heart rate and routine hematological and biochemical evaluations did not show any significant difference in the pre–post values. IVA significantly decreased the resting heart rate after eight weeks of intervention.

Conclusions:

Both antianginal agents appeared equiactive. However, RAN had a better safety and tolerability profile than IVA. Serum sickness-like reaction was an adverse event noticed with IVA, which needs causality establishment.