Benefits of Heart Rate Slowing With Ivabradine in Patients With Systolic Heart Failure and Coronary Artery Disease

Heart rate (HR) is a risk factor in patients with chronic systolic heart failure (HF) that, when reduced, provides outcome benefits. It is also a target for angina pectoris prevention and a risk marker in chronic coronary artery disease without HF. HR can be reduced by drugs; however, among those used clinically, only ivabradine reduces HR directly in the sinoatrial nodal cells without other known effects on the cardiovascular system. This review provides current information regarding the safety and efficacy of HR reduction with ivabradine in clinical studies involving >36,000 patients with chronic stable coronary artery disease and >6,500 patients with systolic HF. The largest trials, Morbidity-Mortality Evaluation of the I_f Inhibitor Ivabradine in Patients With Coronary Disease and Left Ventricular Dysfunction and Study Assessing the Morbidity-Mortality Benefits of the I_f Inhibitor Ivabradine in Patients With Coronary Artery Disease, showed no effect on outcomes. The Systolic Heart Failure Treatment With the I_f Inhibitor Ivabradine Trial, a randomized controlled trial in >6,500 patients with HF, revealed marked and significant HR-mediated reduction in cardiovascular mortality or HF hospitalizations while improving quality of life and left ventricular mechanical function after treatment with ivabradine. The adverse effects of ivabradine predominantly included bradycardia and atrial fibrillation (both uncommon) and ocular flashing scotomata (phosphenes) but otherwise were similar to placebo. In conclusion, ivabradine improves outcomes in patients with systolic HF; rates of overall adverse events are similar to placebo.

The efficacy and safety of ivabradine hydrochloride versus atenolol in Chinese patients with chronic stable angina pectoris

PURPOSE

The aim of this study was to assess the efficacy and safety of ivabradine (Iva) noninferiority to atenolol (Aten) in Chinese patients with chronic stable angina pectoris.

METHODS

In this double-blind, double-dummy trial, patients with symptomatic angina pectoris and positive exercise tolerance test were randomized into the Iva [5 or 7.5 mg bis in die (BID)] or Aten group (12.5 or 25 mg BID) according to computer-generated random numbers for 12 weeks.

RESULTS

One hundred and sixty-eight patients were randomized to the Iva group and 166 to the Aten group. In a full analysis set, increases in the total exercise duration (TED) were 54.3 ± 120.1 seconds with Iva 5 mg and 58.8 ± 114.7 seconds with Aten 12.5 mg at the fourth week, and at the 12th week, TED improved by 84.1 ± 130.5 seconds with Iva and 77.8 ± 126.6 seconds with Aten (95%CI: -21.4-34.1 seconds, p = 0.0011 for noninferiority). The analysis of per protocol set yielded similar results (95%CI: -31.4-33.0 seconds, p = 0.0131 for noninferiority). Heart rate was reduced in both groups at rest and during peak exercise. There were small, nonsignificant differences in the number of adverse events between the two groups (66 in Iva and 73 in Aten, p > 0.05). Nine patients (5.42%) were reported to develop phosphenes/luminous phenomena and blurred vision in the Iva group (p = 0.0035).

CONCLUSIONS

Iva is effective in reducing heart rates and improving exercise capacity and noninferior to Aten in Chinese patients with chronic stable angina pectoris. Iva is well tolerated and safe.