Catheter Ablation -> SVT/AVNRT/WPW/AT: -> Ablation Techniques D-AB07 - Alternate Techniques in Energy Sources (ID 6) Abstract Plus

D-AB07-02 - First Preclinical And Clinical Demonstration Of Transient Myocardial Stunning / Reversible Electroporation With Pulsed Field Energy: A Novel Electrophysiological Maneuver (ID 1420)


Background: Pulsed field ablation (PFA) at ablative doses results in irreversible electroporation and cell death.
Objective: To assess the preclinical and clinical feasibility of reversible electroporation (RE) with a short PFA pulse delivered from a focal PFA catheter.
Methods: Abbreviated biphasic pulses were delivered using a 9mm lattice-tip catheter, compatible mapping system, and programmable PFA generator (Sphere-1, Prism-1, HexaPulse; Affera Inc) in both 6 swine (n=8 LA/RA sites), and in 5 pts (n=8 LA sites) as part of a first in human trial (NCT04141007). In pts, RE was tested pre-ablation in the anticipated path of the PV isolation line. Pre- and post-delivery minielectrode bipolar EGMs were recorded for each application. For analysis, EGMs from the highest amplitude 1-2 electrodes were selected for serial measurement over 2-5 min. In preclinical cases, i) minimum pacing thresholds at 1.0 ms pulse width were assessed from all minielectrodes before and after delivery at 4 sites, and ii) high density mapping of these sites was repeated pre-sacrifice at 12.2±1.3 days follow up.
Results: In swine, EGMs acutely decreased from 1.39±0.84 to 0.31±0.15 mV (P=0.009), but recovered up to 71% over 5 min. The patient trend was similar: the mean EGM amplitude acutely decreased to only 24% of baseline (P=0.004), but then recovered up to 81% of baseline over 3 min. Pacing thresholds increased from <1.0 mA at baseline to >10.0 mA, and recovered to 2.3±1.8 mA. Follow up mapping revealed no low voltage (<0.5mV) at or around these RE sites. (Histology is pending.)
Conclusion: Reversible electroporation is feasible, and provides a unique opportunity for probing tissue physiologically prior to ablation.