Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Ablation Techniques D-PO02 - Poster Session II (ID 47) Poster

D-PO02-190 - The Optimal Size Of Rotational Activities Identified By The Multi-electrode Catheter During Clinical AF Rotor Mapping (ID 247)

 C. Chiang: Nothing relevant to disclose.


Background: The mismatch between the area of rotational wavefront and the coverage of the multi-electrode catheter could compromise the detection of rotors.
Objective: We investigated whether there is an optimal ratio of the size of the rotor to a specific multi-electrode catheter by both simulation model and clinical data.
Methods: The propagations of wavefronts of variable-sized stable rotors (8~42mm) were modeled by the Cellular automaton (CA) method in the 2D atrial substrate(Fig A). The EGMs were recorded from the simulated substrate by a 20 electrodes/5 spines (Pentaray) and the rotor was detected in the presence of phase singularity (PS). In clinical study, we enrolled 24 pts with persistent AF, and performed mapping with Carto 3 (UDM version). The high electrogram similarity (SI) regions were identified and rotors were confirmed by the presence of PS.
Results: In the simulation model, the rotors with diameter of 26~36 mm were most likely identified by the 32mm Pentaray (Fig B), since the PS lasted for more than 3~4 cycles/sec, corresponding to the high SI region. In clinical observation, we determine a total of 97 regions (4±2.6/per pt) with high SI (≥ 0.55, area= 405±425 mm2) as rotors (Figure C). High SI regions with diameters 15~30 mm were the most likely spots of rotational activity (red in Fig C), rather than focal activities (blue in Fig C). Rotor detection rate was higher when the diameter of the multi-electrode increase (P<0.05, Fig C).
Conclusion: The simulation model and clinical observation demonstrated the rotors are more likely detected by a size-matched multi-electrode catheter. The rotor smaller than the multi-electrode catheter may be misinterpreted as focal activities