Abstract 18990: Impact of Cavotricuspid Isthmus Dependent Right Atrial Flutter Ablation on the Incidence and Recurrence of Atrial Fibrillation

Background: There is limited data evaluating the impact of cavotricuspid isthmus ablation for right Atrial Flutter (AFL) on the a) development of Atrial Fibrillation (AF) in those without AF and b) recurrence of AF in patients with previous AF. Methods: We studied all consecutive patients (with or without previous AF) undergoing cavotricuspid isthmus ablation for symptomatic drug resistant AFL in a large academic center. Results: 302 patients underwent AFL ablation between 2007 and 2011. Mean age was 65 yrs with 71% males. Mean left ventricular ejection fraction was 51±14%. Median duration since diagnosis of AFL was 2 months (IQ range 1-10) months. 136 (45%) patients had a history of AF (paroxysmal in 95%) and the remaining 166 (55%) patients did not have AF. Patients “with AF” were more likely to be females, have a previous stroke, had higher CHADS2 score, larger left atria and used more antiarrhythmics prior to ablation. 33 (25%) patients “with AF” had AF in the lab spontaneously, by programmed stimulation or with isoproterenol infusion when compared to 11(7%) patients “without AF”; p<0.001. After a mean follow-up time of 24 months, 95 (31%) patients were on antiarrhythmics (46% vs 19% in patients with and without AF respectively). During follow up, 75 (55%) of the patients “with AF”, had a recurrence of AF and 36 (22%) patients “without AF” group developed AF; p<0.001. The predictors of AF during follow up were female gender (p=0.03), number of antiarrhythmics used (p=0.009) and AF induction during the procedure (p<0.001). AF induction during the procedure predicted AF recurrence in patients “with AF” (p=0.020) but not in patients “without AF” (p=0.243). Conclusions: At 2 years after AFL ablation a) 22% of the patients with isolated AFL develop AF and b) 45% of the patients with previous AF did not have AF recurrence. AF induction during the procedure predicts recurrence of AF after AFL ablation.