What arrhythmia can be effectively treated with lidocaine?

Lidocaine is primarily used as an antiarrhythmic medication, especially for treating ventricular arrhythmias. It is particularly effective in managing ventricular tachycardia, particularly in cases where the arrhythmia is associated with ischemic heart disease or myocardial infarction. Lidocaine works by blocking sodium channels, thereby stabilizing the cardiac membrane and reducing abnormal electrical conduction in the heart. This action helps restore normal rhythm and slows down the heart rate during episodes of ventricular tachycardia.

The use of lidocaine in other arrhythmias, such as paroxysmal supraventricular tachycardia, atrial fibrillation, or atrial flutter, is less effective due to the different mechanisms driving those arrhythmias. Instead, other medications and treatments are typically employed for such conditions, which is a critical point in understanding the specific applications of lidocaine in clinical settings.