Progress continues in the quest to cure atrial fibrillation with catheter ablation techniques

Over the past 5 years, the electrophysiology community has been focused on the development of catheter ablation techniques and ablation systems to cure atrial fibrillation. This endeavour has been fuelled by a number of factors including: (1) the clinical importance of atrial fibrillation because of its high prevalence in the general population, associated symptoms, stroke risk, and increased mortality, (2) the limited efficacy, side effects, and risks associated with pharmacological therapy, and (3) demonstration of the feasibility of curing atrial fibrillation with catheter ablation techniques. Swartz and colleagues were the first to demonstrate that atrial fibrillation can be cured using catheter ablation techniques. These authors reported that creation of linear lesions in the right and left atrium results in a progressive increase in the organization of atrial activity until sinus rhythm is restored. The placement of the lesion lines was designed to emulate those placed surgically in the Maze procedure developed by Cox et al.. Long term cure of atrial fibrillation was achieved in 23 of 29 patients. Although these results demonstrated that catheter ablation of atrial fibrillation using a catheter-based Maze procedure was feasible, the extremely arduous nature of this procedure — with prolonged procedure and fluoroscopy times, the frequent need for second ablation procedures, and the development of several major complications — made it clear that this procedure was not appropriate for widespread clinical use without major advances in the technology of creating linear atrial lesions. Trials are now underway using newer catheter ablation systems designed specifically to facilitate the creation of continuous linear lesions. Almost simultaneous with Swartz’s work, Haissaguerre and colleagues began a series of investigations into the role of catheter ablation in the treatment of atrial fibrillation. An initial series of three patients who underwent successful ablation of atrial fibrillation was published in 1994. In each of these patients, atrial fibrillation was determined to arise from a ‘focal source’ located near the sinus node, mid lateral right atrium, and as a result of atrial flutter.