Experimental model for paroxysmal atrial fibrillation arising at the pulmonary vein-atrial junctions
Experimental model for paroxysmal atrial fibrillation arising at the pulmonary vein-atrial junctions
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DOI：
10.1016/j.hrthm.2005.11.008
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发表时间：
2006-02-01
期刊：
影响因子：
5.5
通讯作者：
Jackman, WM
中科院分区：
文献类型：
--
作者：
Po, SS;Scherlag, BJ;Jackman, WM
背景肺静脉（PV）异位活动并随后引发和维持心房颤动（AF）的机制仍知之甚少。本研究的目的是建立由PV引起的急性AF动物模型。方法在11只犬中，进行胸廓切开术，将连接有聚乙烯管的26号针插入PV底部含有自主神经节的脂肪垫中。将11只犬分为两组：乙酰胆碱（ACh）1-10 mM（组1，n = 5）或卡巴胆碱（CARB）1-10 mM（第11组，n = 6）注射结果在向脂肪垫中注射拟副交感神经药后2至5分钟内，出现一系列心率减慢，自发性过早去极化，在11只狗中的4只中观察到自发性AF。在7只狗中，单次过早的额外刺激容易诱发AF。AF持续时间平均为10分钟（ACh）和38分钟（CARB），在邻近脂肪垫的肺静脉-心房交界处观察到最短AF周期长度（ACh的AF周期长度为75 +/- 41 ins，CARB为37 +/- 12 ms）结论脂肪垫内注射拟副交感神经药引起的急性自主神经重构可导致自发性或易诱发的持续性房颤，且房颤周期短;在邻近注射脂肪垫的肺静脉和心房中观察到最快的放电速率。这些发现类似于患者的阵发性AF，表明自主神经节过度活跃可能是PV引起的局灶性AF患者的关键因素。
BACKGROUND The mechanism(s) by which pulmonary veins (PVs) become ectopically active and subsequently initiate and sustain atrial fibrillation (AF) remains poorly understood.OBJECTIVES The purpose of this study was to produce air acute canine model of paroxysmal AF arising from the PVs.METHODS In 11 dogs, a thoracotomy was performed and a 26-gauge needle with a polyethylene tube attached was inserted into a fat pad containing autonomic ganglia at the base of the PV. The I I dogs were divided into two groups: acetylcholine (ACh) 1-10 mM (group 1, n = 5) or carbachol (CARB) 1-10 mM (group 11, n = 6) injected (0.5 mL) into the fat pad.RESULTS Within 2 to 5 minutes after injection of parasympathomimetics into the fat pad, a sequence of heart rate slowing, spontaneous premature depolarizations, and spontaneous AF was observed in four of 11 dogs. In seven dogs, single premature extrastimuli easily induced AF. AF was sustained for an average of 10 minutes (ACh) and 38 minutes (CARB), with the shortest AF cycle length seen at the PV-atrial junction adjacent to the fat pad (AF cycle length 75 +/- 41 ins for ACh and 37 +/- 12 ms for CARB).CONCLUSION Acute autonomic remodeling produced by injection of parasympathomimetics into the fat pad resulted in spontaneous or easily induced sustained AF with short AF cycle length; the most rapid firing rate was observed in the PV and atria adjacent to the injected fat pad. These findings resemble paroxysmal AF in patients, suggesting that hyperactive autonomic ganglia may be a critical element in patients exhibiting focal AF arising from the PV.