EComment. Atrial ablation in high-risk cardiac surgery patients: Pipe dream or sensible strategy?

Abstract

Over the past two decades, growing attention has been paid to the prevalence and treatment of preoperative atrial fibrillation (AF) in patients scheduled for open heart surgery. AF has become widespread in our aging population. The number of patients with AF is estimated to triple over the next 50 years [1]. It is widely recognized that AF is associated with increase in the risk of stroke and of premature death. Saxena et al. evaluated the impact of preoperative AF (PAF) on early and mid-term outcomes after aortic valve replacement (AVR) and concomitant coronary artery bypass grafting (CABG) [2]. Patients who underwent surgical ablation were excluded from this study. Their most important finding was a reduced mid-term survival after concomitant AVR-CABG surgery in patients with PAF. The authors suggest that these patients be considered for concomitant surgical ablation. The prevalence of PAF in patients scheduled for cardiac surgery is 6-10% [3], but may be higher, rising to even more than 60% in mitral valve patients [4]. According to European guidelines, all cardiac surgery patients with symptomatic PAF should be offered concomitant perioperative ablation (recommendation Class IIa, Level A) [5]. These guidelines also recognize that surgical ablation may be performed in asymptomatic patients with PAF (Class IIb, Level C). How well these recommendations are followed remains unknown. There is no data in the literature describing the proportion of PAF patients who undergo cardiac surgery with and without concomitant ablation (it is not reported by Saxena et al. either). In the real world, it is not uncommon that when concentrating on a complex cardiac procedure, heart surgeons often fail to treat AF. Novel ablation devices that are easily used during cardiac surgery have made the remarkably invasive cut-and-sew technique redundant and have weakened the sceptical surgeon's claim that this is a high-risk procedure. However, as there are so many different types of surgical ablation, occasional inferior results, and no clear recommendations from international surgical societies, AF surgery remains in the hands of its enthusiasts only. Moreover, an effective surgical approach to atrial fibrillation requires adequate understanding of electrophysiology, experience in using ablation devices, and usually a lot of patience. Although we surgeons strive to be patient, we feel better when the operation proceeds quickly, and putting complex lesion sets on both atria certainly does not accelerate the procedure. The more difficult question concerns patients who undergo complex cardiac surgery and suffer PAF. Why does successful surgical treatment of atrial fibrillation remain only a pipe dream for some of them? Who are the candidates for whom it would be a sensible strategy? Saxena et al. reported that PAF is an independent risk factor for mid-term mortality in patients undergoing complex cardiac surgery. There is a clear need for randomized studies comparing patients being and not being treated for PAF during complex surgical procedures. The lack of clear guidelines based on results from multiple randomized clinical trials is depriving some of our patients the chance to undergo effective treatment, and it is putting others under greater risk of prolonged surgery. Centres well-experienced in AF surgery need to address this issue and deliver valid data to us. Conflict of interest: none declared.