%0 Journal Article
%T Application Repetition and Electrode-Tissue-Contact Results in Deeper Lesions Using a Pulsed-Field Ablation Circular Variable Loop Catheter.
%A Di Biase L
%A Marazzato J
%A Gomez T
%A Byun E
%A Zou F
%A Grupposo V
%A Mohanty S
%A La Fazia VM
%A Ammirati G
%A Lin A
%A Garcia DY
%A Della Rocca D
%A Al Ahamad A
%A Schiavone M
%A Gasperetti A
%A Freilich M
%A Serna JC
%A Forleo G
%A Liu X
%A Lakkireddy D
%A Tondo C
%A Natale A
%A Zhang XD
%J Europace
%V 0
%N 0
%D 2024 Aug 16
%M 39150065
%F 5.486
%R 10.1093/europace/euae220
%X <B>BACKGROUND: </B>Pulsed field ablation (PFA) is a novel, myocardial-selective, non-thermal ablation modality used to target cardiac arrhythmias. Although prompt EGM signal disappearance is observed immediately after PFA application in the pulmonary veins, whether this finding results in adequate transmural lesions is unknown.<BR><B>OBJECTIVE: </B>If application repetition and catheter-tissue contact impact on lesion formation during PFA.<BR><B>METHODS: </B>A circular loop PFA catheter was used to deliver repeated energy applications with various levels of contact-force. A benchtop vegetal potato model and a beating heart ventricular myocardial model were utilized to evaluate the impact of application repetition, contact force, and catheter repositioning on contiguity and lesion depth. Lesion development occurred over 18 hours in the vegetal model and over 6 hours in the porcine model.<BR><B>RESULTS: </B>Lesion formation was found to be dependent on application repetition and contact. In porcine ventricles, single and multiple stacked applications led to a lesion depth of 3.5 ± 0.7 mm and 4.4 ± 1.3 mm, respectively (p =0.002). Furthermore, the greater the catheter-tissue contact, the more contiguous and deeper the lesions in the vegetal model (1.0±0.9 mm with no contact Vs. 5.4±1.4 mm with 30 g of force; p=.0001).<BR><B>CONCLUSIONS: </B>PFA delivered via a circular catheter showed that both repetition and catheter contact led independently to deeper lesion formation. These findings indicate that endpoints for effective PFA ablation are more related to PFA biophysics than mere EGM attenuation.