The mechanism underlying proarrhythmia is often related to the interference with cardiac ion channels, which play a critical role in the electrical activity of the heart. Many antiarrhythmic drugs target ion channels such as sodium, potassium, and calcium channels. When these drugs alter ion channel function, they can disrupt the normal cardiac action potential, leading to arrhythmias. For instance, the blockade of potassium channels can prolong the cardiac action potential, increasing the risk of torsades de pointes, a specific form of proarrhythmia.
