Limited role for ivabradine in the treatment of chronic heart failure.

Abstract

To quantify the proportion of patients attending a community heart failure clinic with left ventricular systolic impairment who might be suitable for ivabradine therapy. High resting heart rate is an important and potentially modifiable risk factor in patients with heart failure. The SHIFT study suggested that ivabradine was beneficial when added to conventional treatment including a β-blocker in heart failure patients in sinus rhythm whose resting heart rates remained 70 beats per minute (bpm) or greater and who had worse than moderate left ventricular impairment. The primary cohort included 2211 patients with a left ventricular ejection fraction (LVEF) of 50% or less. Patients were seen at baseline, then reviewed at 4 and 12 months. 'Suitability' for ivabradine was assessed as: LVEF 35% or less, sinus rhythm and a resting heart rate of 70 bpm or greater. The proportion of patients who were 'suitable' for ivabradine therapy fell from 19.4% (n=429) at baseline, to 14.1% (n=185) at 4 months and finally 9% (n=82) by the 12-month clinic visit. The proportion fell to 5.3% (n=48) if only patients with New York Heart Association class I symptoms and/or no β-blocker therapy were excluded. After uptitration of heart failure medications, the number of patients 'suitable' for ivabradine therapy was small. First and foremost, β-blocker therapy should be commenced and titrated. The decision to add ivabradine should be made after allowing adequate time to uptitrate conventional medical therapy.