Tovmassian Lilith, Maille Baptiste, Koutbi Linda, Hourdain Jérôme, Martinez Elisa, Zabern Maxime, Deharo Jean-Claude, Franceschi Frédéric
Department of Cardiology, CHU Timone, Marseille, France.
Aix-Marseille Université, Faculté de Médecine,Marseille, France.
Front Cardiovasc Med. 2022 Feb 8;9:814026. doi: 10.3389/fcvm.2022.814026. eCollection 2022.
Compound motor action potential (CMAP) monitoring is a common method used to prevent right phrenic nerve palsy during cryoballoon ablation for atrial fibrillation.
We compared recordings simultaneously obtained with surface and hepatic electrodes.
We included 114 consecutive patients (mean age 61.7 ± 10.9 years) admitted to our department for cryoballoon ablation. CMAP was monitored simultaneously with a hepatic catheter and a modified lead I ECG, whilst right phrenic nerve was paced before (stage 1) and during (stage 2) the right-sided freezes. If phrenic threat was detected with hepatic recordings (CMAP amplitude drop >30%) the application was discontinued with forced deflation.
The ratio of CMAP/QRS was 4.63 (2.67-9.46) for hepatic and 0.76 (0.55-1.14) for surface ( < 0.0001). Signal coefficients of variation during stage 1 were 3.92% (2.48-6.74) and 4.10% (2.85-5.96) ( = 0.2177), respectively. Uninterpretable signals were more frequent on surface (median 10 vs. 0; < 0.0001). For the 14 phrenic threats, the CMAP amplitude dropped by 35.61 ± 8.27% on hepatic signal and by 33.42 ± 11.58% concomitantly on surface ( = 0.5417). Our main limitation was to achieve to obtain stable phrenic capture (57%). CMAP monitoring was not reliable because of pacing instability in 15 patients (13.16%). A palsy occurred in 4 patients (3.51%) because cryoapplication was halted too late.
Both methods are feasible with the same signal stability and amplitude drop precocity during phrenic threats. Clarity and legibility are significantly better with hepatic recording (sharper signals, less far-field QRS). The two main limitations were pacing instability and delay between 30% CMAP decrease and cryoapplication discontinuation.
复合肌肉动作电位（CMAP）监测是在房颤冷冻球囊消融过程中预防右侧膈神经麻痹的常用方法。
我们比较了同时使用体表电极和肝脏电极获得的记录。
我们纳入了114例连续入住我科接受冷冻球囊消融的患者（平均年龄61.7±10.9岁）。在右侧冷冻前（阶段1）和冷冻期间（阶段2），同时使用肝脏导管和改良I导联心电图监测CMAP，同时对右侧膈神经进行起搏。如果肝脏记录检测到膈神经受威胁（CMAP波幅下降>30%），则停止操作并强制放气。
肝脏记录的CMAP/QRS比值为4.63（2.67 - 9.46），体表记录的为0.76（0.55 - 1.14）（<0.0001）。阶段1期间信号变异系数分别为3.92%（2.48 - 6.74）和4.10%（2.85 - 5.96）（P = 0.2177）。体表不可解读信号更常见（中位数为10对0；<0.0001）。对于14次膈神经受威胁情况，肝脏信号上CMAP波幅下降35.61±8.27%，体表同时下降33.42±11.58%（P = 0.5417）。我们的主要局限性是实现稳定的膈神经夺获（57%）。由于15例患者（13.16%）起搏不稳定，CMAP监测不可靠。4例患者（3.51%）发生了麻痹，原因是冷冻操作停止过晚。
两种方法都是可行的，在膈神经受威胁时信号稳定性和波幅下降早熟情况相同。肝脏记录的清晰度和易读性明显更好（信号更清晰，远场QRS更少）。两个主要局限性是起搏不稳定以及CMAP下降30%与停止冷冻操作之间的延迟。
