Management of Atrial Fibrillation: Simplicity Surrounded by Controversy

Atrial fibrillation appears to be the most common sustained tachyarrhythmia encountered in clinical practice; it increases in frequency with age and the presence of structural heart disease [1]. It has neither the glamour of the Wolff-Parkinson-White syndrome nor the drama of sudden cardiac death, and it appears to be simple to treat. Yet no other arrhythmia is surrounded by so much controversy with regard to management strategies.

Three major tenets govern therapy for atrial fibrillation: maintenance of sinus rhythm, control of ventricular rate, and prevention of thromboembolism. The relative benefit of sinus rhythm over a controlled fibrillating rate is controversial. The advantages of sinus rhythm include elimination of arrhythmic symptoms; improvement in the hemodynamic profile; possible prevention of established (cardioversion-resistant) atrial fibrillation; and a likely, although unproven, decrease in the risk for cardiac thromboemboli [1-3]. Because antiarrhythmic drugs are the method most commonly used to maintain sinus rhythm, the major associated risks are pharmacologic side effects, including potentially lethal ventricular arrhythmias [4]. Judicious selection of antiarrhythmic drugs, done on the basis of the causes of atrial fibrillation and the type of cardiac pathology, and initiation of therapy in the hospital in selected patients should decrease the incidence of and the morbidity and mortality associated with such arrhythmias [5].

Regardless of the potential benefits of sinus rhythm, many physicians think that the risks of drug therapy and the difficulty of maintaining sinus rhythm are arguments for the alternative approach to the treatment of atrial fibrillation: ventricular rate control. In the absence of congestive heart failure, verapamil, diltiazem, and β-adrenergic blockers are more effective than digoxin for long-term control [1]. If this approach to atrial fibrillation is chosen, it is important to document good rate control (for example, with 24-hour electrocardiography) because patients who have persistently elevated …