Relationship between rotors and complex fractionated electrograms in atrial fibrillation using a novel computational analysis.

Introduction: Rotors and complex fractionated atrial electrograms (CFAEs) have been suggested as possible therapeutic targets in ablation of atrial fibrillation (AF). The aim of this study was to assess the relationship between rotors and CFAEs in patients with AF.

Methods: We studied 18 patients with AF (mean age 69±8 years, 33% female) who underwent rotor ablation and pulmonary vein isolation. Endocardial mapping was performed with a basket catheter to identify the presence, number and location of rotors and CFAEs. The FIRM™ (Abbott) and CARTO™ (Biosense) systems were used with overlapping of frames from continuous 30-s recordings. CFAEs were classified as stable if present in >15 frames, moderately stable if present in 10-15 frames and unstable if present in 5-9 frames.

Results: A total of 44 rotors and 60 CFAEs (39 of them stable) were identified. The mean number of rotors and stable CFAEs per patient was 2.6±1.4 and 2.2±1.5, respectively. In 27 of the 44 identified rotors, CFAEs were found in the same location. Conversely, in 20 of the 39 stable CFAEs identified, a focal rotor was found in the same location. The majority of CFAEs found at the same location as a focal rotor were stable (63% vs. 37%, p=0.001).

Conclusion: Rotors and CFAEs are frequently found in the same location within the atria, particularly when only stable CFAEs are considered. This relationship may have implications in the selection of substrate targets for ablation.