Which irregular heartbeat condition is Procainamide primarily used to treat?

Procainamide is primarily used to treat ventricular tachycardia, a condition characterized by an abnormally fast heart rate originating from the lower chambers of the heart (ventricles). It is classified as a Class IA antiarrhythmic medication, which means it helps to restore normal heart rhythm by blocking sodium channels during the depolarization phase of cardiac action potentials.

In the context of ventricular tachycardia, Procainamide works to normalize conduction in the heart and can help stabilize the rhythm, making it particularly effective in managing this condition. While it may have some limited use in other types of arrhythmias, its primary indication remains the treatment of ventricular tachycardia where rapid heart rates can lead to more serious complications, including decreased cardiac output and potential progression to ventricular fibrillation.