Curative ablation for atrial fibrillation: what clinical trials do we need to establish efficacy.
In contrast to other supraventricular tachycardias, curative treatment of atrial fibrillation, although increasingly available and rapidly evolving, is neither as effective nor the first choice. Until recently, the unavailability of nonsurgical curative treatment may have fueled a debate on the relative importance of restoring sinus rhythm versus controlling the ventricular rate during atrial fibrillation. Recent randomized trials (PIAF, AFFIRM, and RACE) using very limited atrial fibrillation burden assessment show that pharmacologic ventricular rate control is much safer and possibly more effective than pharmacologic restoration of sinus rhythm. A clinical trial comparing a truly curative treatment of atrial fibrillation-such as catheter ablation targeting pulmonary vein isolation-with pharmacologic treatment is required. It should focus on reliable efficacy parameters, use vigilant assessment of safety, and, most importantly, be structured to provide all-important prognostic information on long-term outcome. Atrial fibrillation burden is a theoretically robust efficacy parameter, but accurate quantification over a sufficiently long period of monitoring will require technologically innovative noninvasive rhythm monitoring devices.