Department of Cardiac, Thoracic and Vascular Sciences and Public Health, University of Padua, Padova, Italy.
Electrophysiology, Cardiology Unit, Civil Hospital, Mestre-Venice, Italy.
Int J Cardiol. 2021 Apr 15;329:99-104. doi: 10.1016/j.ijcard.2020.12.075. Epub 2021 Jan 4.
Catheter ablation of the specialized atrioventricular junction (AVJ) with a right-side approach is an effective therapy for refractory atrial fibrillation with fast ventricular rate. Our aim is to assess the efficacy of the procedure in a single center experience and investigate the histologic findings of AVJ after catheter ablation.
A) Analysis of AVJ ablation efficacy in a consecutive series of patients with refractory atrial fibrillation; B) Histopathologic study of the conduction system by serial section technique and clinical-electrophysiologic correlation in four patients who underwent AVJ ablation.
A) Right-sided AVJ ablation was successful in all 87 consecutive patients (mean procedural time 19.2±17.9 min). Energy applications ranged from 1 to 27 (mean 5.8±5.1) with eight patients (9%) requiring > 15 applications. B) Fibrotic disruption of atrioventricular (AV) node and/or His bundle interruption was found in three cases with previous AVJ ablation. In the case requiring a left side approach, the compact AV node and common His bundle appeared undamaged whereas extensive fibrosis of the summit of the ventricular septum, branching His bundle and proximal bundle branches was found. Noteworthy, a continuity between the septal and anterior tricuspid valve leaflets was present.
Our data confirm that the ideal site for ablation of the specialized AVJ is the AV node. In selected cases with unsuccessful AV node ablation, a shift towards the His bundle is needed. A continuity between the septal and anterior leaflets of the tricuspid valve may protect the His bundle as to require multiple shocks and prolong the procedure.
经右侧入路消融房室结（AVJ）是治疗快速心室率的难治性心房颤动的有效方法。我们的目的是评估单一中心经验中该程序的疗效，并研究 AVJ 消融后的组织学发现。
A）在连续系列的难治性心房颤动患者中分析 AVJ 消融的疗效；B）在 4 例行 AVJ 消融的患者中，采用连续切片技术进行传导系统的组织病理学研究和临床电生理相关性研究。
A）87 例连续患者均成功进行了右侧 AVJ 消融（平均手术时间 19.2±17.9 分钟）。能量应用范围为 1 至 27（平均 5.8±5.1），8 例（9%）患者需要>15 次应用。B）在 3 例既往 AVJ 消融患者中发现房室（AV）结和/或希氏束纤维性中断。在需要左侧入路的情况下，致密 AV 结和共同希氏束似乎未受损，而室间隔顶部、分支希氏束和近端束支广泛纤维化。值得注意的是，室间隔和前三尖瓣瓣叶之间存在连续性。
我们的数据证实，消融特殊 AVJ 的理想部位是 AV 结。在 AV 结消融不成功的情况下，需要向希氏束转移。三尖瓣瓣间隔和前瓣之间的连续性可能会保护希氏束，从而需要多次电击并延长手术时间。
