I-f modulation: perspectives in clinical medicine

As opposed to a number of other pharmacological agents, ivabradine expresses high selectivity and specificity for its target. Ivabradine exerts a unique action on cardiac pacemaker activity, based on its block of the hyperpolarization-activated, cyclic nucleotide-gated channels that pass the pacemaker current, If. In doing so, it suppresses but does not stop the sinoatrial pacemaker's rate of firing. In the following pages, we will review the mechanisms of normal pacemaker activity in the heart, discuss ivabradine's mechanism of action, and then review the advantages of heart rate reduction in clinical settings as well as other potential applications of the drug.