Department of Cardiology, Asklepios Clinic St. Georg, Faculty of Medicine, Semmelweis University Campus Hamburg, Hamburg, Germany.
Department of Cardiac Electrophysiology, Heart and Vascular Centre, University Hospital Hamburg Eppendorf, Hamburg, Germany.
PLoS One. 2020 Jun 25;15(6):e0235132. doi: 10.1371/journal.pone.0235132. eCollection 2020.
Phrenic nerve injury (PNI) remains one of the most frequent complications during cryoballoon-based pulmonary vein isolation (CB-PVI). Since its introduction in 2013, the use of compound motor action potential (CMAP) for the prevention of PNI during CB-PVI is increasing; however, systematic outcome data are sparse.
The CMAP technique was applied in conjunction with abdominal palpation during pacing manoeuvres (10 mV, 2 ms) from the superior vena cava for 388 consecutive patients undergoing CB-PVI between January 2015 and May 2017 at our tertiary arrhythmia centre. Cryoablation was immediately terminated when CMAP amplitude was reduced by 30%.
Reductions in CMAP amplitude were observed in 16 (4%) of 388 patients during isolation of the right veins. Of these, 11 (69%) patients did not manifest a reduction in diaphragmatic excursions. The drop in CMAP amplitude was observed in 10 (63%) patients during ablation of the right superior pulmonary veins (PVs) and in 7 (44%) patients during ablation of the right inferior PVs. Postprocedural persistent PNI was observed in three of four patients for a duration of 6 months, with one of these patients remaining symptomatic at the 24-month follow-up. One of the four patients was lost to long-term follow-up.
All PNIs occurred during right-sided CB-PVI and were preceded by a reduction in CMAP amplitude. Thus, the standardized use of CMAP surveillance during CB-PVI is easily applicable, reliable and compared with other studies, results in a lower number of PNIs.
膈神经损伤（PNI）仍然是基于冷冻球囊的肺静脉隔离（CB-PVI）过程中最常见的并发症之一。自 2013 年引入以来，使用复合运动动作电位（CMAP）来预防 CB-PVI 过程中的 PNI 的情况越来越多；然而，系统的结果数据仍然很少。
在我们的三级心律失常中心，2015 年 1 月至 2017 年 5 月期间，对 388 例连续患者在进行 CB-PVI 时，使用 CMAP 技术在膈神经起搏操作（10 mV，2 ms）时结合腹部触诊，从上腔静脉进行。当 CMAP 幅度降低 30%时，立即终止冷冻消融。
在隔离右静脉的过程中，388 例患者中有 16 例（4%）观察到 CMAP 幅度降低。其中，11 例（69%）患者的膈肌运动幅度没有降低。在消融右肺上静脉（PVs）时，10 例（63%）患者和消融右肺下 PVs 时，7 例（44%）患者观察到 CMAP 幅度下降。在四个有持续性 PNI 的患者中，有三个在 6 个月时持续存在，其中一个在 24 个月随访时仍有症状。四个患者中有一个失去了长期随访。
所有 PNI 均发生在右侧 CB-PVI 期间，且均先出现 CMAP 幅度降低。因此，标准化使用 CB-PVI 期间的 CMAP 监测易于应用、可靠，并且与其他研究相比，PNI 的数量更少。
