Both procainamide and lidocaine are useful for acutely treating cardiac arrhythmias, and procainamide can be useful in chronic antiarrhythmic regimens. Successful management of cardiac arrhythmias requires knowledge of: 1) the mechanism and natural history of the arrhythmia, 2) the physiologic state of the patient, and 3) the cardiac effects, pharmacodynamics, and general pharmacology of the antiarrhythmic drugs
