Catheter ablation of atrial fibrillation

Abstract

The impact of atrial fibrillation on the healthcare systems of Western countries is overwhelming, due to its independent association with death, systemic thromboembolism, impaired quality of life and hospitalizations. Catheter ablation is the only treatment thus far demonstrated capable of achieving cure in a substantial proportion of patients. Pulmonary vein antrum isolation (PVAI) is the cornerstone of current atrial fibrillation ablation techniques, with the greatest efficacy as a stand-alone procedure in patients with paroxysmal atrial fibrillation. Use of general anesthesia, open-irrigated ablation catheters and maintenance of periprocedural therapeutic warfarin has been demonstrated to increase the safety and effectiveness of PVAI. In patients with paroxysmal atrial fibrillation, the systematic addition of superior vena cava isolation increases the long-term freedom from atrial fibrillation recurrence. A more extensive ablation approach extending to the entire left atrial posterior wall and to complex fractionated electrograms (CFAEs) is warranted in nonparoxysmal atrial fibrillation patients, in whom nonpulmonary vein trigger sites are frequently identified. Up to one-third of these patients experiencing atrial fibrillation recurrence after ablation have evidence of triggers from the left atrial appendage. Isolation of this structure is the best treatment strategy to improve the long-term success rate. In recent years, in addition to the development of ablation techniques to increase the success rate, outcomes of atrial fibrillation treatment trials have been reconsidered. In particular, reduction of hospitalization, stroke and mortality, as well as economic factors, have all been considered relevant to evaluate the effectiveness of atrial fibrillation treatment. Large ongoing trials are specifically evaluating the impact of atrial fibrillation ablation on these outcomes. This article will summarize the state-of-the art techniques for atrial fibrillation ablation, and will discuss the contribution of ongoing studies to the future of atrial fibrillation ablation.