Class 1 antiarrhythmic agents for therapy of atrial fibrillation.

Atrial fibrillation is most the common sustained arrhythmia seen by the cardiologist. Therapy to prevent this arrhythmia is often prescribed so as to eliminate associated symptoms which include palpitations, fatigue, dizziness and presyncope, shortness of breath, congestive heart failure and emboli, especially those that result in a cerebrovascular accident. Pharmacologic therapy is the only effective therapy for preventing atrial fibrillation and the class 1 antiarrhythmic drugs remain the most frequently used agents. Although each of these agents has been reported to be effective for preventing atrial fibrillation, they are associated with frequent side effects, some of which are potentially serious, especially aggravation of arrhythmia. Prior to treatment the benefit vs risk of these drugs for each patient must be established.