Right atrial flutter as a marker of biatrial substrate for atrial fibrillation: Is more always better?

Abstract

Dear Editor; We read with great interest the article by Koerber and colleagues1 titled “Prophylactic Pulmonary Vein Isolation (PVI) during Cavotricuspid Isthmus (CTI) Ablation for Atrial Flutter (AFl): A Meta-Analysis” about the importance of the prophylactic PVI during CTI ablation on long-term atrial fibrillation (AF) recurrence without significantly increasing major complications. Despite the increased procedure and fluoroscopy times, there was no significant increase in major complications.1 We want to address some points that merit more attention and would like to hear author s opinions about the importance of prophylactic PVI in the current era of only symptomatic relive of AF ablation.2–4 Although CTI is considered curative therapy for typical AFl, many patients develop an AF after ablation during a long-term follow-up period and maintained over time.5 It seems probable that the variability in the reported incidence of postablation AF is related in large part to varying intensities of monitoring. Although no patients had a prior diagnosis of AF in these studies, it is certainly possible that many were already having silent episodes prior to ablation.6 As authors stated, both the REDUCE AF7 (Pulmonary Vein Isolation to Reduce Future Risk of Atrial Fibrillation in Patients Undergoing Typical Flutter Ablation: Results from a Randomized Pilot Study) and the PREVENT-AF (Prophylactic pulmonary vein isolation during isthmus ablation for atrial flutter)8 trials reveled that prophylactic PVI reduced new-onset AF and burden in patients with lone AFl during clinical follow-up, with consequent reduction in hospitalizations and need to perform repeat ablation for AF. As expected, the procedure times were longer with combined approach. The main finding in current meta-analysis also was the significant reduction in recurrent atrial arrhythmias with prophylactic PVI at the time of CTI for typical AFl among subjects without a prior history of AF.1 AFl and AF could be manifestations of a more general electrophysiologic disease,9 perhaps; these results are not unexpected if we consider the pathophysiology of the both atrial diseases, which may share common triggers and arrhythmogenic substrate in a background of biatrial fibrosis. Therefore, the eradication of the flutter circuit will not prevent the eventual manifestation of AF.10 However, no ablation is free from risk and these must be weighed against the potential benefit, and the only AFl patients at very high risk of AF might theoretically benefit from prophylactic PVI.6 TheHATCH score (which is based on hypertension, age ≥75 years, transient ischemic attack