Four recent randomized controlled studies that compared rhythm control versus rate control therapy demonstrated that rate control therapy is an acceptable alternative to rhythm control therapy. The control of heart rate achievable with pharmacologic therapy is imperfect and, in many patients, difficult to obtain. Ablation and pacing therapy offers better control of heart rate than drug therapy.
The aim of the PAF 2 trial was to evaluate the effect of antiarrhythmic drug therapy on long-term maintenance of normal sinus rhythm after ablation and pacing therapy and to evaluate the effect of maintenance of normal sinus rhythm on major clinical events, quality of life and cardiac performance and, therefore, to evaluate whether antiarrhythmic drug strategy yields any additional benefit to ablation and pacing therapy. In this multicenter randomized controlled trial, 68 patients with severely symptomatic paroxysmal atrial fibrillation were assigned, after successful atrioventricular junction ablation and pacing treatment, to antiarrhythmic drug therapy with amiodarone, propafenone, flecainide or sotalol and were compared with 69 patients assigned, after successful AV junction ablation and pacing treatment, to no antiarrhythmic drug therapy. Although patients in the antiarrhythmic drug arm had a reduction in the risk of developing chronic atrial fibrillation, there was no clinical benefit beyond that obtained with ablation and pacing alone. On the contrary, antiarrhythmic therapy was associated with more serious adverse clinical events, i.e. episodes of heart failure and hospitalization. This suggests that the control of ventricular rhythm by ablation and pacing has a greater beneficial effect on short-term clinical outcome than the preservation of atrial contraction. Therefore, the results of PAF2 study are consistent with the drug trials comparing rhythm and rate control.
atrial fibrillation - catheter ablation - pacing - antiarrhythmic drug therapy - quality of life