背景:-基于心内膜导管的心室心肌脉冲场消融(PFA)是有前途的。然而,关于PFA靶向腔内结构的能力知之甚少,心外膜,以及通过厚心室组织实现透壁病变的方法。方法:-在全身麻醉下,使用格状尖端导管将双相单极PFA输送到猪心室,通过电解剖标测,透视和心内超声心动图(ICE)指导。我们进行了实验,以评估重复单极PFA应用于消融的可行性和安全性:i)腔内乳头状肌和减速带,ii)心外膜目标,和iii)用于室间隔和左心室(LV)游离壁中的心肌中段目标的双极PFA。结果:-i)成功消融乳头状肌(n=13),然后在第2、7和21天进行评估。9个有稳定接触的病变,测量长度为18.3≥2.4mm,15.3≥1.5mm宽,2天深度5.8≥1.0mm。慢性病变显示腱索保留,无二尖瓣返流。两个有针对性的调节带在没有结构破坏的情况下被经壁消融。ii)成功获得了经饱和盐水/二氧化碳辅助的心外膜通路,心外膜单极病变的平均长度,宽度,深度30.4≥4.2mm,23.5≥4.1mm,和9.1≥1.9mm,分别。iii)双极PFA病变穿过隔膜(n=11)和LV游离壁(n=7)。12个完成的双极病变的平均长度,宽度,深度29.6≥5.5mm,21.0≥7.3mm,14.3≥4.7mm,分别。长期而言,这些病变表现出均匀的纤维化变化,没有组织破坏。双极病变明显比单极心外膜病变深。结论:-该体内评估表明PFA可以成功消融腔内结构,形成深心外膜病变和透壁LV病变。
UNASSIGNED: Endocardial catheter-based pulsed field ablation (PFA) of the ventricular myocardium is promising. However, little is known about PFA\'s ability to target intracavitary structures, epicardium, and ways to achieve transmural lesions across thick ventricular tissue.
UNASSIGNED: A lattice-tip catheter was used to deliver biphasic monopolar PFA to swine ventricles under general anesthesia, with electroanatomical mapping, fluoroscopy and intracardiac echocardiography guidance. We conducted experiments to assess the feasibility and safety of repetitive monopolar PFA applications to ablate (1) intracavitary papillary muscles and moderator bands, (2) epicardial targets, and (3) bipolar PFA for midmyocardial targets in the interventricular septum and left ventricular free wall.
UNASSIGNED: (1) Papillary muscles (n=13) were successfully ablated and then evaluated at 2, 7, and 21 days. Nine lesions with stable contact measured 18.3±2.4 mm long, 15.3±1.5 mm wide, and 5.8±1.0 mm deep at 2 days. Chronic lesions demonstrated preserved chordae without mitral regurgitation. Two targeted moderator bands were transmurally ablated without structural disruption. (2) Transatrial saline/carbon dioxide assisted epicardial access was obtained successfully and epicardial monopolar lesions had a mean length, width, and depth of 30.4±4.2, 23.5±4.1, and 9.1±1.9 mm, respectively. (3) Bipolar PFA lesions were delivered across the septum (n=11) and the left ventricular free wall (n=7). Twelve completed bipolar lesions had a mean length, width, and depth of 29.6±5.5, 21.0±7.3, and 14.3±4.7 mm, respectively. Chronically, these lesions demonstrated uniform fibrotic changes without tissue disruption. Bipolar lesions were significantly deeper than the monopolar epicardial lesions.
UNASSIGNED: This in vivo evaluation demonstrates that PFA can successfully ablate intracavitary structures and create deep epicardial lesions and transmural left ventricular lesions.