Abstract
Aims. Complex fractionated electrogram (CFE) ablation in addition to pulmonary vein isolation is an accepted strategy for the treatment of non-paroxysmal atrial fibrillation (AF). We sought to determine the effect of flecainide on the distribution and extension of CFE areas. Methods. Twenty-three non-paroxysmal AF patients were enrolled in this prospective study. A first CFE map was obtained under baseline conditions by sampling 5 s of continuous recording from the distal electrodes of the ablation catheter. Intravenous flecainide (1 mg/kg) was administered over 10 min and followed by 30-min observation time. A second CFE map was obtained with the same modalities. CFE-mean values, CFE areas, and atrial electrogram amplitude were retrieved from the electro-anatomical mapping system (Ensite NavX). Results. After flecainide administration, CFE-mean values increased (111.5 ± 55.3 vs. 132.3 ± 65.0 ms, p < 0.001) with a decrease of CFE area (32.9%) in all patients. Atrial electrogram amplitude decreased significantly (0.30 ± 0.31 vs. 0.25 ± 0.20 mV, p < 0.001). We observed 80.9% preservation of CFE areas. A CFE mean of 78 ms was the best cutoff for predicting stable CFE areas. Conclusions. Flecainide reduces the extension of CFE areas while preserving their spatial localization. A CFE-mean value <80 ms may be crucial to define and locate stable CFE areas.
Acknowledgement
We acknowledge the collaboration and technical support of Peter Schuster and Li-Zhi Sun.
Declaration of interest: The authors report no declarations of interest. The authors alone are responsible for the content and writing of the paper.
This work was supported by funding from Helse-Vest, Norway. The study has been presented in part at the Annual Meeting of the Heart Rhythm Society, Denver, CO, May 2013.