BACKGROUND Pulsed field ablation (PFA) has emerged as an alternative to radiofrequency ablation. However, data on focal point-by-point PFA are scarce. The aim of this study was to compare lesion durability and collateral damage between focally delivered unipolar/biphasic PFA versus radiofrequency in swine. METHODS Eighteen swine were randomized to low-dose PFA, high-dose PFA, and radiofrequency using a multimodality generator. Radiofrequency delivered by market-available generator served as control group. A contact force-sensing catheter was used to focally deliver PFA/radiofrequency at the pulmonary veins and other predefined sites in the atria. Animals were remapped postprocedurally and 28 days postablation to test lesion durability followed by gross necroscopy and histology. RESULTS All targeted sites were successfully ablated (contact force value, 13.9±4.1 g). Follow-up remapping showed persistent pulmonary vein isolation in all animals (100%) with lesion durability at nonpulmonary vein sites proven in most (98%). Regardless of the energy source used, the lesion size was similar across the study groups. Transmurality was achieved in 95% of targeted sites and 100% at pulmonary veins. On histology, PFA animals showed more mature scar formation than their radiofrequency counterpart without myocardial necrosis or inflammation. Finally, no sign of collateral damage was observed in any of the groups. CONCLUSIONS In a randomized preclinical study, focally delivered unipolar/biphasic PFA guided by contact force values was associated with durable lesions on chronic remapping and with mature scar formation on histology without signs of collateral injury on necroscopy. Further studies are needed to investigate the long-term feasibility of this new approach to atrial fibrillation treatment.

中文翻译：

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使用多模态发生器和接触力感应消融导管进行逐点脉冲场消融：与重新映射的慢性猪心脏中的射频消融进行比较。

背景技术脉冲场消融（PFA）已经作为射频消融的替代方案出现。然而，有关逐点 PFA 的数据很少。本研究的目的是比较猪体内局灶性单极/双相 PFA 与射频的病变持久性和附带损害。方法 18 只猪被随机分配接受低剂量 PFA、高剂量 PFA 和使用多模态发生器的射频治疗。由市场上可用的发生器提供的射频作为对照组。使用接触力感应导管在肺静脉和心房的其他预定部位集中输送 PFA/射频。手术后和消融后 28 天对动物进行重新定位，以测试病变持久性，然后进行大体尸检和组织学检查。结果 所有目标部位均成功消融（接触力值，13.9±4.1 g）。后续重新映射显示所有动物（100%）都有持续的肺静脉隔离，大多数动物（98%）的非肺静脉部位的病变持久。无论使用何种能源，各研究组的病变大小相似。95% 的目标部位实现了透壁，100% 的肺静脉实现了透壁。在组织学上，PFA 动物比射频动物表现出更成熟的疤痕形成，没有心肌坏死或炎症。最后，在任何一组中都没有观察到附带损害的迹象。结论 在一项随机临床前研究中，由接触力值引导的局灶性单极/双相 PFA 与慢性重新映射中的持久损伤以及组织学上的成熟疤痕形成相关，而尸检中没有附带损伤的迹象。需要进一步的研究来调查这种房颤治疗新方法的长期可行性。