Ivabradine has a unique mechanism of action and should not be used in all patients. It acts on a specialized muscle that regulates the heart rate in our body (called the pacemaker) and reduces the heart rate. If you have to use Ivabradine, the heart should be in normal rhythm called the sinus rhythm (which means you should not have any irregular heartbeats or abnormal rhythms), your heart rate should not be abnormally low (not less than 70 beats per minute), and your heart is pumping lesser blood than what is safe (ejection fraction ≤ 35%).