Catheter Ablation -> SVT/AVNRT/WPW/AT: -> Ablation Techniques D-PO05 - Poster Session V (ID 39) Poster

D-PO05-151 - Feasibility And Safety Of Temperature Guided Ablation (TGA) Of The Cavo-tricuspid Isthmus After Pulmonary Vein Isolation: A First In Man Experience (ID 1280)


Background: 3.5-mm radiofrequency (RF) catheters are widely used to ablate the cavotricuspid isthmus (CTI) after pulmonary vein isolation (PVI). Temperature-guided ablation (TGA) is a novel mode of RF ablation allowing high power RF in a low-flow setting via a new catheter equipped with micro-thermocouples and mini-electrodes.
Objective: To evaluate ‘first in man’ the feasibility and safety of TGA to achieve CTI block after PVI.
Methods: TGA was evaluated in 10 consecutive patients undergoing CTI-ablation after PVI. Power was set at 50 watts (W) and temperature threshold for flow increase at 40°C. RF was delivered up to an ablation index (AI) of 500 at sites revealing high-frequency potentials recorded by the mini-electrodes. Procedural parameters were compared to the last 20 patients that underwent CTI-ablation after PVI with a conventional (CONV) non-porous RF catheter (35W, AI 500, intertag distance ≤ 6mm).
Results: TGA resulted in CTI block after 5.0±1.3 RF applications with an RF delivery time of 118±27 seconds (vs 11.0±3.1 applications and 204±55 seconds in the CONV group, both p<0.05). Median power in TGA was 50W (vs 35W in CONV, p<0,05). Intertag distance in TGA was 6.5±1.0mm (vs 5.2±0.6 mm in CONV, p<0,05). In TGA, the micro-electrograms (and not the tip-ring electrogram) identified discrete zones of high-frequency potentials. One steam pop was observed in the TGA group.
Conclusion: TGA seems a highly effective ablation mode, with less than 2 minutes of RF to achieve CTI block after PVI. This is most likely related to the combination of high power and increased resolution of electrogram recording. Further studies are needed to evaluate safety.