MOA of Ivabradine 


Ivabradine is a heart rate-lowering medication that acts by selectively and specifically inhibiting the cardiac pacemaker current, a mixed sodium-potassium inward current that controls the spontaneous diastolic depolarization in the sinoatrial (SA) node and hence regulates the heart rate.

Ivabradine binds to the HCN channel protein, which is responsible for generating the funny current. This binding blocks the channel and prevents the funny current from flowing. As a result, the SA node cells depolarize more slowly, which leads to a lower heart rate.


Ivabradine does not affect myocardial contraction, relaxation, or ventricular repolarization. This is because it does not affect other ion channels in the heart, such as the calcium channels or sodium channels.

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