不同部位刺激诱发心房颤动时碎裂电位的出现与分布

目的 探讨在心房和肺静脉不同部位行电刺激诱发心房颤动（简称房颤）时碎裂电位（CFAEs）的出现与分布。方法 22只成年健康杂种犬,常规麻醉,气管插管,切断双侧颈迷走神经干,破坏颈交感神经节,建立动物的去自主神经模型。双侧开胸,分别在右心耳、左心耳和四支肺静脉的近、中、远段行电刺激诱发房颤,观察在基础刺激、双侧强迷走刺激两种诱发条件下,房颤发作时CFAEs的分布情况。结果 刺激诱发房颤的部位与CFAEs出现的部位并不完全一致。双侧心房（心耳）及肺静脉口附近是房颤时CFAEs出现的高频部位。当伴有迷走神经刺激时,房颤的诱发率提高,CFAEs的出现频率也随之明显增加。结论 房颤时CFAEs的分布并不局限于心房或肺静脉的某一局部区域,而是在多个部位可同时标测到。迷走刺激条件下标测到CFAEs的频率增加。

The frequency and distribution of complex fractionated atrial electrograms in a canine model of atrial fibrillationinduced by local electrical stimulation

Objective To investigate the frequency and distribution of complex fractionated atrial electrograms （CFAEs） in a canine model of atrial fibrillation （AF） induced by local electrical stimulation at different sites in the atria and 4 pulmonary veins （PVs） . Methods In 22 mongrel dogs, the cervical vagal trunks were isolated bilaterally and decentralized. Local burst stimulation （ S1S1 = 80 ms, impulse duration 0.5 ms ） and programmed stimulation were per- formed to right appendage （RAA） , left appendage （LAA） and different sites of 4 PVs. AF inducibility and CFAEs were determined at each site in the baseline state and during bilateral cervical vagal nerve stimulation （VNS, 12.5 Hz, impulse duration 0.5 ms, stimulation voltage 5-8 V）. Results The sites of local electrical stimulation initiating AF were not at the same location as those of the CFAEs. CFAEs were observed more frequently at RAA, LAA and the proximal portions of 4 PVs during AF. The prevalence of CFAEs was higher during VNS. Conclusion It is more common to map CFAEs at several sites of PVs during AF. VNS increases the frequency of CFAEs.