Characteristics and distribution of complex fractionated atrial electrograms in patients with paroxysmal and persistent atrial fibrillation

Substrate-based radiofrequency ablation for treatment of atrial fibrillation (AF) is still under development. The purpose of this study was to investigate the different characteristics and distribution of complex fractionated atrial electrograms (CFAE) in both atria in patients with paroxysmal and persistent AF.

The NavX™ system was used to map the left and right atria and the coronary sinus in 20 AF patients (ten persistent). An automated algorithm calculates the average time interval between consecutive deflections (complex fractionated electrogram (CFE) mean). All recordings were visually inspected off-line and interpreted either as continuous, fragmented, mixed CFAE, or non-CFAE, and their locations were determined. Electrograms with intermittent CFAE characteristics were also regarded as non-CFAEs. There were more CFAEs in persistent AF than in paroxysmal AF (52% vs. 44% of total registrations, p < 0.05), and CFAEs were more widespread in both atria in persistent AF patients. There were also more continuous CFAEs (70% vs. 59% of total CFAEs, p < 0.05), and less mixed and intermittent CFAEs (22% vs. 30% and 16% vs. 21% of total CFAEs, respectively, p < 0.05) in persistent AF. Fragmented CFAEs had more high-voltage signals than other groups. Employing the automated algorithm for CFAE mapping, a CFE mean cut-off value of ≤80 ms provides a sensitivity and specificity of 87.4% and 81.2%, respectively.

CFAEs distribute in preferential areas and arrange in different patterns in both atria. Patients with persistent AF have more continuous CFAEs and higher temporal signal stability than patients with paroxysmal AF.