sentences:  Several agents called "heart rate reducing agents" act by specifically inhibiting f-channel function.Ivabradine is the most specific and selective If inhibitor and the only member of this family that is now marketed for pharmacological treatment of chronic stable angina in patients with normal sinus rhythm who have a contraindication or intolerance to beta-blockers.Recent studies have also indicated that funny channel inhibition can be used to reduce the incidence of coronary artery disease outcomes in a subgroup of patients with heart rate ≥70 bpm.