Can the Response to Antiarrhythmic Drugs Prior to Catheter Ablation Predict Long-Term Outcomes of Catheter Ablation for Persistent Atrial Fibrillation

Aim: Anti-arrhythmic drugs (AADs) can be used for chemical cardioversion (CV) or as an adjunct of CV using DC in patients with persistent atrial fibrillation (PeAF). We investigated whether PeAF patients who have a history of restoring sinus rhythm (SR) by only AADs have better outcome of Catheter ablation (CA), compared to those without response to AADs. Methods: 155 patients with PeAF were enrolled. AADs include amiodarone, propafenone and flecainide. A positive response to AADs was defined as conversion to the SR within 1 week after AADs were taken. Results: Forty-two patients out of the 155 patients (34%) had a positive response to AADs: 31 to amiodarone, 13 to flecainide, and 6 to propafenone. One hundred twenty one out of 141 patients had a history of successful CV prior to CA. In univariate analysis, no significant correlation was observed between responses to AADs and AF recurrence after CA, however, in multivariate analyses, hypertension, age, responses to AADs were significant predictors of AF recurrence after CA (p=0.010, p=0.049, and p=0.025, respectively). Conclusions: In addition to hypertension and age, response to oral AADs prior to CA, which may closely relate to the chronicity of AF, strongly predicted the outcome after CA of PeAF.