Effect of Inter-Electrode Spacing on the Complex Fractionated Atrial Electrogram Detection and the Dominant Frequency

Abstract

Background: Complex fractionated atrial electrograms (CFAEs) have been used as targets for ablation during atrial fibrillation. Dominant frequency (DF) has also been shown to be related to center of rotor focal firing. We hypothesized that CFAEs and DF may be influenced by inter-electrode spacing (IES). Methods: Bipolar electrograms were recorded for 5 seconds using 2-mm spacing octapolar catheter from left atrium during AF where CFAEs were identified by Navx. Bipolar electrograms from different IES (from 1–2 to 1–6) were recorded and analyzed by EP Logic software. Results: The fractionation interval decreased with increasing IES (70±18 vs. 59±8 vs. 55±5 vs. 57±9 vs. 56±10 ms, from electrodes 1–2 to 1–6; p<0.05 respectively). There was no difference in DF from different IES. However, RI and OI decreased with increasing IES (RI, 0.29±0.11 vs. 0.25±0.12 vs. 0.23±0.11 vs. 0.20±0.10 vs. 0.18±0.11, from electrodes 1–2 to 1–6; p<0.01 respectively: OI, 0.40±0.15 vs. 0.35±0.13 vs. 0.32±0.13 vs. 0.29±0.11 vs. 0.28±0.11, from electrodes 1–2 to 1–6; p<0.05 respectively). Conclusions: CFAEs detection was related to the IES, but DF was not influenced by IES. Increased RI and OI were related to the CFAE detection.