EComment. Surgery to treat atrial fibrillation: Which technique is the best?

Abstract

I read with interest the article by Basu et al [1]. There is no doubt that bipolar radiofrequency (RF) ablation is better than unipolar RF ablation to cure the atrial fibrillation (AF) because of the full transmurality achieved almost exclusively by the bipolar RF. I have discussed this matter previously [2,3]. The presumed basis of successful AF ablation is production of myocardial lesions that block the propagation of AF wave fronts from a rapidly firing triggering source or modification of the arrhythmogenic substrate responsible for re-entry. Successful ablation depends upon achieving lesions that are reliably transmural. The hypothetical scenario with the patient described by Basu et al. [1] corresponds to a Class IIa indication with supporting evidence graded as level C for concomitant surgical ablation of AF, according to the Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation [4]. Whether simple pulmonary vein (PV) isolation or a more complete Cox-maze IV procedure with irrigated bipolar RF ablation is performed may perhaps be the most important point of discussion in this paper. On the one hand, it is well known that paroxysmal AF triggers occurs into the pulmonary veins up to 90% of the cases. In other words, simple PV isolation has a limited success in eliminating AF . On the other hand, the Cox-maze III procedure, when properly performed in a standard “cut-and-sew” fashion, cures AF in nearly 100% of the patients with or without concomitant disease [5]. However, the long aortic clamp times have always been the hallmark of this procedure. Simplification of the maze procedure has evolved toward newer streamlined surgical approaches using different ablation tools. Irrigated bipolar RF ablation seems to be the more effective to reach to goal. Nevertheless, the success rate of curing AF remains limited. In fact, until now there is no paper in the literature demonstrating an effectiveness of 100% with the electric Cox-maze IV procedure. Finally, we should keep in mind that in the real world the Cox-maze III “cut-and-sew” standard procedure is reserved only to a select number of cardiac surgeons because of its high surgical complexity. In conclusion, I think that bipolar RF ablation is better than unipolar RF ablation in treating AF. Procedures that are more complete than simple PV isolation such as the electric Cox-maze IV with bipolar RF ablation must be performed. If the case is treated within an experienced and referral centre, the Cox- maze III “cut-and-sew” is the standard procedure of choice to eliminate AF. Conflict of Interest: None declared