B-AB03-01 DOSE-DEPENDENT TRANSIENT AV NODAL CONDUCTION BLOCK USING REVERSIBLE ELECTROPORATION

Abstract

Membrane pores created with pulsed electrical fields (PF) can be reversible if delivered sub-threshold allowing for purposeful reversible electroporation (RE) of tissue. To evaluate the response of AV node to RE pulses in a preclinical model. Under general anesthesia, percutaneous femoral venous access was obtained in two swine. Abbreviated pulses were delivered to the AV node area using a 9mm lattice-tip catheter with varying PF waveforms using a custom mapping system and PF generator (Sphere-9, Prism-1, HexaPulse; Affera Inc, MA). RE pulses were delivered at either low-dose or high-dose. AV conduction was monitored following delivery. In sinus rhythm, a His potential was successfully recorded. A total of 9 low-dose and 7 high-dose RE pulses were delivered. Immediately following low-dose applications, PR prolongation (median 104 ms, IQR 10, 232ms) was observed in 7 of 9 applications (no change in 2 of 9); there was complete recovery to baseline in 6 of 7 within 4.7±3.7sec (the last 1 of 7 recovered to 10ms of baseline after 64 sec of observation). With high-dose RE, complete AV block occurred in 6 of 7 (PR prolongation in the remaining 1 of 7); there was complete recovery to baseline in 5 of 7 in 152±84 sec (the last 2 of 7 both recovered to within 30ms of baseline after 56 and 710 sec of observation, respectively). Pulsed electrical fields can be employed in a manner as to cause reversible conduction block of AV conduction in a dose-dependent manner. If reproduced clinically in other myocardial tissues, this introduces a potentially novel approach to interrogating arrhythmias.