Department of Cardiovascular Medicine, Toho University Graduate School of Medicine.
Department of Cardiovascular Medicine, Toho University Faculty of Medicine.
Int Heart J. 2021;62(1):87-94. doi: 10.1536/ihj.20-636.
Intracardiac defibrillation (IDF) is performed to restore sinus rhythm (SR) during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). This study aimed to investigate the change in the IDF threshold before and after RFCA during the ablation procedure and determine whether the IDF threshold after RFCA was associated with the AF substrate and AF recurrence. A total of 141 consecutive patients with drug-refractory persistent AF (age 62.5 ± 10.3 years, 84.4% male) were enrolled in this study. Before RFCA, we initially performed IDF with an output of 1 J. When IDF failed to restore SR, the output was gradually increased to 30 J. After RFCA, we attempted pacing-induced AF to provoke other focuses of AF. When AF was induced, we performed IDF again to terminate AF with outputs of 1 to 30 J. The change in the IDF threshold to restore SR before and after RFCA was evaluated. After RFCA, the IDF threshold for restoring SR significantly decreased (from 11.5 ± 8.6 J to 4.0 ± 3.8 J, P < 0.001). During the follow-up (24.3 ± 12.2 months), SR was maintained in 107 patients (75.9%). The multivariate analysis using a Cox proportional-hazards model revealed that an IDF threshold of > 5 J after RFCA was significantly associated with the AF recurrence (HR, 3.99; 95% confidence interval 1.93-8.22; P = 0.0001). RFCA decreased the IDF threshold for restoring SR in patients with persistent AF. The IDF output of > 5 J after RFCA could be a predictor of AF recurrence independent of the AF substrate.
心内除颤（ICD）用于在房颤（AF）的射频导管消融（RFCA）期间恢复窦性心律（SR）。本研究旨在探讨消融过程中 RFCA 前后 ICD 阈值的变化，并确定 RFCA 后 ICD 阈值是否与 AF 底物和 AF 复发相关。本研究共纳入 141 例药物难治性持续性 AF 患者（年龄 62.5±10.3 岁，84.4%为男性）。在 RFCA 之前，我们最初以 1 J 的输出进行 ICD。当 ICD 未能恢复 SR 时，输出逐渐增加至 30 J。在 RFCA 之后，我们尝试起搏诱导 AF 以引发其他 AF 病灶。当诱导出 AF 时，我们再次进行 ICD 以 1 至 30 J 的输出终止 AF。评估 RFCA 前后恢复 SR 的 ICD 阈值变化。RFCA 后，恢复 SR 的 ICD 阈值显著降低（从 11.5±8.6 J 降至 4.0±3.8 J，P<0.001）。在随访期间（24.3±12.2 个月），107 例患者（75.9%）维持 SR。使用 Cox 比例风险模型的多变量分析显示，RFCA 后 ICD 阈值>5 J 与 AF 复发显著相关（HR，3.99；95%置信区间 1.93-8.22；P=0.0001）。RFCA 降低了持续性 AF 患者恢复 SR 的 ICD 阈值。RFCA 后 ICD 输出>5 J 可能是独立于 AF 底物预测 AF 复发的指标。
