Abstract
Pulsed field ablation (PFA) is a novel nonthermal therapy for cardiac arrhythmias. The influence of contact force (CF), contact status, and application count on lesion characteristics in bipolar biphasic circular PFA remains uncertain. This study investigated lesion dimensions and acute histopathological changes using potato and porcine myocardial models. PFA was delivered in potato models under non-contact conditions or stratified contact forces (0–25 g, 25–50 g, > 50 g; 5 applications each). Porcine myocardium lesions were created with 1, 3, or 5 applications under contact or non-contact. Contact conditions yielded deeper lesions than non-contact in potato models (p < 0.001), with no significant differences among CF subgroups. In porcine myocardium, contact lesions were significantly deeper after three (4.82 ± 0.91 mm vs. 3.33 ± 0.74 mm; p < 0.05) and five applications (5.80 ± 0.49 mm vs. 3.55 ± 0.45 mm; p < 0.001) compared to non-contact. Lesion width was unaffected by contact status or application number. Histology demonstrated contraction-band necrosis, neutrophilic infiltration, edema, and hemorrhage with preserved microvasculature; these changes were more pronounced under contact. In the phantom model, lesion dimensions were predominantly governed by contact stability rather than contact force magnitude. In vivo validation confirmed that maintaining stable contact is a prerequisite for effective lesion formation. Furthermore, increasing the number of applications augmented lesion depth in porcine myocardium, while width remained stable.
Data availability
The data that support the findings of this study are available from the corresponding author on reasonable request.
References
Tabaja, C. et al. Catheter-Based Electroporation: A Novel Technique for Catheter Ablation of Cardiac Arrhythmias. JACC Clin. Electrophysiol. 9, 2008–2023. https://doi.org/10.1016/j.jacep.2023.03.014 (2023).
Natale, A. et al. Catheter ablation for atrial fibrillation: indications and future perspective. Eur. Heart J. 45, 4383–4398. https://doi.org/10.1093/eurheartj/ehae618 (2024).
Reddy, V. Y. et al. Pulsed Field or Conventional Thermal Ablation for Paroxysmal Atrial Fibrillation. N Engl. J. Med. 389, 1660–1671. https://doi.org/10.1056/NEJMoa2307291 (2023).
Verma, A. et al. Pulsed Field Ablation for the Treatment of Atrial Fibrillation: PULSED AF Pivotal Trial. Circulation 147, 1422–1432. https://doi.org/10.1161/circulationaha.123.063988 (2023).
Reissmann, B., Metzner, A. & Kuck, K. H. Cryoballoon ablation versus radiofrequency ablation for atrial fibrillation. Trends Cardiovasc. Med. 27, 271–277. https://doi.org/10.1016/j.tcm.2016.12.002 (2017).
Deering, T. F. et al. Pulsed field ablation: A promise with future broad-based applicability or a pause needing further analysis-Is catheter ablation at a crossroads? A critical appraisal of the new challenger-pulsed field ablation. Heart rhythm. 21, 1242–1244. https://doi.org/10.1016/j.hrthm.2024.03.1763 (2024).
Reichlin, T. et al. Pulsed Field or Cryoballoon Ablation for Paroxysmal Atrial Fibrillation. N Engl. J. Med. 392, 1497–1507. https://doi.org/10.1056/NEJMoa2502280 (2025).
Scacciavillani, R. et al. Safety and Feasibility of Pulsed-Field Ablation in Patients With Mechanical Prosthetic Valves. JACC Clin. Electrophysiol. 11, 98–106. https://doi.org/10.1016/j.jacep.2024.09.025 (2025).
Reddy, V. Y. et al. Pulsed Field Ablation of Persistent Atrial Fibrillation With Continuous ECG Monitoring Follow-Up: ADVANTAGE AF-Phase 2. Circulation (2025). https://doi.org/10.1161/circulationaha.125.074485
Sauer, W. H. & Kreidieh, O. Precision Medicine and Ablation of Ventricular Arrhythmias: The Difficulty of Estimating Lesion Size and Durability. JACC Clin. Electrophysiol. 9, 341–344. https://doi.org/10.1016/j.jacep.2022.10.037 (2023).
Mulder, M. J., Kemme, M. J. B. & Allaart, C. P. Radiofrequency ablation to achieve durable pulmonary vein isolation. Europace: Eur. pacing Arrhythm. cardiac Electrophysiol. : J. working groups cardiac pacing Arrhythm. cardiac Cell. Electrophysiol. Eur. Soc. Cardiol. 24, 874–886. https://doi.org/10.1093/europace/euab279 (2022).
Qian, P. C. et al. Optimizing Impedance Change Measurement During Radiofrequency Ablation Enables More Accurate Characterization of Lesion Formation. JACC Clin. Electrophysiol. 7, 471–481. https://doi.org/10.1016/j.jacep.2020.09.011 (2021).
Steiger, N. et al. Relative contribution of contact force to lesion depth using high-power short-duration radiofrequency applications. Heart rhythm. 21, 1738–1740. https://doi.org/10.1016/j.hrthm.2024.03.042 (2024).
Rozen, G. et al. Prediction of radiofrequency ablation lesion formation using a novel temperature sensing technology incorporated in a force sensing catheter. Heart rhythm. 14, 248–254. https://doi.org/10.1016/j.hrthm.2016.11.013 (2017).
Nakagawa, H. et al. Evaluation of Ablation Parameters to Predict Irreversible Lesion Size During Pulsed Field Ablation. Circ. Arrhythm. Electrophys. 17, e012814. https://doi.org/10.1161/circep.124.012814 (2024).
Okumura, Y. et al. In vivo assessment of catheter-tissue contact using tissue proximity indication and its impact on cardiac lesion formation in pulsed field ablation. Heart rhythm. 22, 952–960. https://doi.org/10.1016/j.hrthm.2024.09.061 (2025).
Reddy, V. Y. et al. The relationship between contact force and clinical outcome during radiofrequency catheter ablation of atrial fibrillation in the TOCCATA study. Heart rhythm. 9, 1789–1795. https://doi.org/10.1016/j.hrthm.2012.07.016 (2012).
Ariyarathna, N., Kumar, S., Thomas, S. P., Stevenson, W. G. & Michaud, G. F. Role of Contact Force Sensing in Catheter Ablation of Cardiac Arrhythmias: Evolution or History Repeating Itself? JACC Clin. Electrophysiol. 4, 707–723. https://doi.org/10.1016/j.jacep.2018.03.014 (2018).
Saito, Y. et al. Clinical importance of tissue proximity indication during pulsed field ablation for atrial fibrillation: insights from initial experience. Heart rhythm. https://doi.org/10.1016/j.hrthm.2025.01.022 (2025).
Groen, M. H. A., Fish, J. M., Loh, P. & van Es, R. Impact of electrode–tissue proximity on formation of pulsed field ablation lesions: Using multi-electrode impedance measurements. Heart rhythm O. 2 6, 1412–1418. https://doi.org/10.1016/j.hroo.2025.05.026 (2025).
Di Biase, L. et al. Application Repetition and Electrode-Tissue-Contact Results in Deeper Lesions Using a Pulsed-Field Ablation Circular Variable Loop Catheter. Europace: Eur. pacing Arrhythm. cardiac Electrophysiol. : J. working groups cardiac pacing Arrhythm. cardiac Cell. Electrophysiol. Eur. Soc. Cardiol. https://doi.org/10.1093/europace/euae220 (2024).
Younis, A. et al. Impact of Contact Force on Pulsed Field Ablation Outcomes Using Focal Point Catheter. Circ. Arrhythm. Electrophys. 17, e012723. https://doi.org/10.1161/circep.123.012723 (2024).
Nakagawa, H. et al. Effects of Contact Force on Lesion Size During Pulsed Field Catheter Ablation: Histochemical Characterization of Ventricular Lesion Boundaries. Circ. Arrhythm. Electrophys. 17, e012026. https://doi.org/10.1161/circep.123.012026 (2024).
Mattison, L. et al. Effect of contact force on pulsed field ablation lesions in porcine cardiac tissue. J. Cardiovasc. Electrophys. 34, 693–699. https://doi.org/10.1111/jce.15813 (2023).
Gasperetti, A. et al. Determinants of acute irreversible electroporation lesion characteristics after pulsed field ablation: the role of voltage, contact, and adipose interference. Europace: Eur. pacing Arrhythm. cardiac Electrophysiol. : J. working groups cardiac pacing Arrhythm. cardiac Cell. Electrophysiol. Eur. Soc. Cardiol. 25 https://doi.org/10.1093/europace/euad257 (2023).
Koya, T. et al. Effects of In Vivo Contact Force on Pulsed-Field Ablation Efficacy in Porcine Ventricles. J. Cardiovasc. Electrophys. 36, 642–649. https://doi.org/10.1111/jce.16581 (2025).
Di Biase, L. et al. Pulsed Field Ablation Index-Guided Ablation for Lesion Formation: Impact of Contact Force and Number of Applications in the Ventricular Model. Circ. Arrhythm. Electrophys. 17, e012717. https://doi.org/10.1161/circep.123.012717 (2024).
Gomes, D. A. et al. Left Atrial Wall Thickness Measured by a Machine Learning Method Predicts AF Recurrence After Pulmonary Vein Isolation. J. Cardiovasc. Electrophys. 36, 323–330. https://doi.org/10.1111/jce.16515 (2024).
Teres, C. et al. Personalized paroxysmal atrial fibrillation ablation by tailoring ablation index to the left atrial wall thickness: the ‘Ablate by-LAW’ single-centre study—a pilot study. EP Europace. 24, 390–399. https://doi.org/10.1093/europace/euab216 (2022).
Falasconi, G. et al. Personalized pulmonary vein antrum isolation guided by left atrial wall thickness for persistent atrial fibrillation. Europace: European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology 25 (2023). https://doi.org/10.1093/europace/euad118
Di Biase, L. et al. Point-by-Point Pulsed Field Ablation Using a Multimodality Generator and a Contact Force-Sensing Ablation Catheter: Comparison With Radiofrequency Ablation in a Remapped Chronic Swine Heart. Circ. Arrhythm. Electrophys. 16, 663–671. https://doi.org/10.1161/circep.123.012344 (2023).
Kueffer, T. et al. Dose-dependent ventricular lesion formation using a novel large-area pulsed field ablation catheter: A preclinical feasibility study. Heart rhythm. https://doi.org/10.1016/j.hrthm.2025.02.017 (2025).
Verma, A., Maffre, J., Sharma, T. & Farshchi-Heydari, S. Effect of Sequential, Colocalized Radiofrequency and Pulsed Field Ablation on Cardiac Lesion Size and Histology. Circulation: Arrhythmia Electrophysiol. 18 https://doi.org/10.1161/circep.124.013143 (2025).
Tam, M. T. K. et al. Effect of Pulsed-Field Ablation on Human Coronary Arteries: A Longitudinal Study With Intracoronary Imaging. JACC Clin. Electrophysiol. 11, 1478–1488. https://doi.org/10.1016/j.jacep.2025.03.014 (2025).
Funding
This work was supported by Science and Technology Department of Sichuan Province (Grant Number: 2024YFFK0046), 1∙3∙5 Project for Disciplines of Excellence-Clinical Research Incubation Project, West China Hospital of Sichuan University (Grant Number: 2023HXFH002). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Author information
Authors and Affiliations
Contributions
Xianjin Hu conceptualized the study, curated and analyzed data, and wrote the original draft; Wenjie Li, Bangjiaxin Ren, Fanghui Li, and Aobo Gong contributed to data analysis and validation; Xianzhao Zhu and Luyang Xie conducted investigation and data curation; Ying Cao and Zexi Li performed visualization and assisted in manuscript writing; Rui Zeng designed the methodology, supervised the project, and revised the manuscript. All authors reviewed and approved the final version.
Corresponding author
Ethics declarations
Competing interests
Xianzhao Zhu and Luyang Xie are employees of Sichuan Jinjiang Electronic Medical Device Technology Co., Ltd. Their roles in the study were limited to: (1) Technical assistance in configuring and calibrating the PFA equipment during experiments. (2) Operational support for the 3D Electroanatomic Mapping System. (3) Data collection and preliminary organization of raw experimental outputs. It is important to note that these two authors were not involved in the design of the experimental protocol, data analysis/interpretation, manuscript preparation, or any decision-making processes related to the study outcomes. Their participation was strictly confined to technical execution under the supervision of the independent research team. All remaining authors have declared no conflicts of interest.
Conflict of interest
Xianzhao Zhu and Luyang Xie are employees of Sichuan Jinjiang Electronic Medical Device Technology Co., Ltd. All remaining authors have declared no conflicts of interest.
Additional information
Publisher’s note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary Information
Below is the link to the electronic supplementary material.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
About this article
Cite this article
Hu, X., Li, W., Ren, B. et al. Impact of contact parameters on lesion dimensions during circular Pulsed-Field ablation in ex vivo and in vivo models. Sci Rep (2026). https://doi.org/10.1038/s41598-026-42503-1
Received:
Accepted:
Published:
DOI: https://doi.org/10.1038/s41598-026-42503-1
