Catheter Ablation -> Ventricular Arrhythmias -> Mapping & Imaging D-PO06 - Poster Session VI (ID 26) Poster

D-PO06-108 - Impact Of Filter Configuration On Bipolar Electrograms (ID 669)

 T. Yamamoto: Nothing relevant to disclose.


Background: The impact of filtering on bipolar electrograms (EGMs) has not yet been systematically examined.
Objective: To assess the impact of filter configuration on bipolar EGMs.
Methods: Five patients with ischemic VT were included. Eight different filter configurations were prospectively created for the distal bipoles of the ablation catheter: 1.0-250Hz, 10-250Hz, 100-250Hz, 30-50Hz, 30-100Hz, 30-250Hz, 30-500Hz and 30-1000Hz. Pre-ablation EGMs with good contact (contact force>10g) were analyzed. Baseline fluctuation, baseline noise, bipolar voltage and presence of local abnormal ventricular activity (LAVA) were compared.
Results: In total, 736 EGMs in 92 sites in the scar were compared as shown in the Figure. Baseline fluctuation was only seen in the configuration where the high-pass filter was ≤10Hz (p<0.001). Noise level was lowest at 30-50Hz (0.015[0.012-0.019]mV), increased as the low-pass filter (LPF) extended, and was highest at 30-1000Hz (0.044 [0.039-0.051]mV) (p<0.001). Conversely, the high-pass filter (HPF) did not affect the noise level at ≤30Hz. As the HPF increased to 100Hz, bipolar voltages significantly decreased (p<0.001), but were not affected when the LPF was increased ≥100Hz. LAVAs were most frequently detected at 30-250Hz and 30-500Hz (77/92 (83.7%)), followed by 100-250Hz and 30-1000Hz (76/92 (82.6%)), but frequently missed at LPF ≤100Hz or HPF ≤10Hz (P<0.001).
Conclusion: Bipolar EGMs are strongly affected by filter setting in scar areas. 30-250Hz or 30-500Hz may be the best configuration in terms of the baseline fluctuation, baseline noise, and LAVA detection.