Introduction
Catheter ablation (CA) of atrial fibrillation (AF) is a well-established procedure for the treatment of drug refractory AF. Single-procedure AF ablation is successful in 60-80% of optimal candidates, but many patients require repeat ablation(1). Atypical atrial flutter (AFL) has been reported in approximately 8% of patients following AF ablation using RF energy(2). Patients with AFL can be very symptomatic and refractory to medical therapy, often requiring repeat ablation procedures. While it is a common belief that the outcomes for repeat ablation procedures in patients who present with atypical AFl are superior to those observed in patients who present with recurrent AF, there are limited data available to support this assumption. This study aimed to describe the electrophysiological findings and the prognostic utility of recurrent atypical AFL versus recurrent AF after index AF ablation in a large contemporary cohort of patients at our center.