Department of Cardiology, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomèdica Sant Pau (IIB SANT PAU), CIBERCV, Universitat Autònoma de Barcelona, Spain (G.A.-F., Z.M.-W., J.M.G.).
Instituto de Investigaciones Biomédicas de Barcelona, (IIBB-)CSIC, CIBERCV, IIB SANT PAU, Spain (S.C.-R.).
Circ Arrhythm Electrophysiol. 2023 Sep;16(9):e011914. doi: 10.1161/CIRCEP.123.011914. Epub 2023 Aug 14.
Pulsed field ablation (PFA) is a novel nonthermal cardiac ablation technology based on irreversible electroporation (IRE). While areas of IRE lead to durable lesions, the surrounding regions, where reversible electroporation occurs, recover. The behavior of local electrograms in areas of different electroporation levels remains unknown. The goal of this study is to characterize electrogram dynamics after PFA in IRE and reversible electroporation areas.
A total of 6 domestic swine were used. PFA was applied in the epicardium of the right and left ventricles using a focal monopolar catheter. Additional radiofrequency ablations were performed. Epicardial unipolar electrograms were acquired at baseline and for 60 minutes post PFA/radiofrequency ablation using a high-density electrode matrix attached to the epicardium. Electrogram dynamics were analyzed in areas corresponding to different levels of electroporation. Acute lesion formation was assessed after 3 to 5 hours by triphenyl tetrazolium chloride staining.
Electrogram analysis demonstrated a clear association between electrogram changes and the level of electroporation. Immediately after PFA, electrograms displayed the following: a significant decrease in R/S-wave amplitude; a large elevation of the ST-segment; and a large decrease in their |(dV/dt)|. Marked changes in electrograms were observed beyond the lesion area. Thereafter, a gradual recovery was observed. The evolution of all the electrogram parameters throughout the 60 minutes after PFA was significantly different (<0.05) between the IRE and reversible electroporation areas. Acute lesion staining showed significantly larger depth for PFA lesions compared with radiofrequency ablation.
This study shows that unipolar electrograms can differentiate between reversible electroporation and IRE areas during the first 30 minutes post ablation. Differences after the first 30 minutes are less evident. Our findings could result useful for immediate lesion assessment after PFA and warrant further investigation.
脉冲场消融（PFA）是一种基于不可逆电穿孔（IRE）的新型非热心脏消融技术。IRE 导致的区域形成持久的病变，而发生可逆电穿孔的周围区域则会恢复。不同电穿孔水平区域的局部电图行为尚不清楚。本研究的目的是描述 PFA 在 IRE 和可逆电穿孔区域后的电图动力学特征。
共使用 6 头国内猪。使用聚焦单极导管在心外膜的右心室和左心室进行 PFA。另外进行射频消融。使用附在心脏外膜的高密度电极矩阵在 PFA/射频消融后即刻和 60 分钟采集心外膜单极电图。在心外膜电描记图对应不同电穿孔水平的区域分析电图动力学。在三苯基四唑氯染色后 3 至 5 小时评估急性病变形成。
电图分析表明电图变化与电穿孔水平之间存在明确的关联。PFA 后即刻，电图显示：R/S 波幅度明显降低；ST 段大幅抬高；|(dV/dt)|大幅降低。在心外膜电图记录的损伤区域以外，观察到明显的电图变化。此后，观察到逐渐恢复。PFA 后 60 分钟内，所有电图参数的演变在 IRE 和可逆电穿孔区域之间均有显著差异（<0.05）。急性病变染色显示 PFA 病变的深度明显大于射频消融。
本研究表明，在消融后 30 分钟内，单极电图可以区分可逆电穿孔和 IRE 区域。30 分钟后差异不太明显。我们的发现可能有助于 PFA 后立即评估病变，并需要进一步研究。
