左上肺静脉脂肪垫对犬心房颤动的影响

Effect of left superior pulmonary vein fat pad on atrial fibrillation in dogs

目的观察射频消融左上肺静脉脂肪垫(left superior pulmonary vein fat pad,LSPV-FP)对心房颤动(AF)的影响。方法 12只健康杂种犬,麻醉插管后持续心电监测;于双侧颈部暴露迷走神经干,左右侧第4肋间开胸并暴露LSPV-FP;分别测量基础、刺激迷走神经、消融LSPV-FP、刺激迷走神经+消融LSPV-FP 4种状态下的心房及左上肺静脉有效不应期(ERP)和有效不应期离散度(dERP)、AF诱发率、AF时心室率。结果基础状态下,刺激左侧或右侧迷走神经干可明显缩短心房ERP[(84.44±29.50)ms vs(129.7±15.83)ms,(85.42±26.11)ms vs(129.7±15.83)ms,P<0.05]、增大dERP[(71.67±14.03)ms vs(34.17±18.32)ms,(57.5±24.17)ms vs(34.17±18.32)ms,P<0.05]、增大左上肺静脉近端与远端ERP的差异(P<0.05)、增加AF的诱发率[(5.33±1.231)次vs(0.75±0.96)次,(4.67±1.155)次vs(0.75±0.96)次,P<0.05]及降低AF时心室率[(143.6±22.42)次/min vs(226.3±28.50)次/min,(146.4±30.72)次/min vs(226.3±28.50)次/min,P<0.05]。消融LSPV-FP可以逆转刺激左侧迷走神经干所致的上述变化(P<0.05),但对右侧迷走神经刺激干所致的电生理变化无显著影响。结论左侧迷走神经干纤维部分通过LSPV-FP对心房颤动的触发或维持发挥作用。

Objective To explore the effect of ablation of left superior pulmonary vein fat pad（LSPV-FP） on atrial fibrillation（AF）.Methods Twelve healthy adult mongrel dogs were anesthetized and ventilated;both cervical vagosympathetic trunks were exposed for stimulation.Thoracotomies at the 4th intercostal space of left and right chest were performed to expose the LSPV-FP.The effective refractory period（ERP）/ERP-dispersion（dERP） of atrium and LSPV,AF inducibility,and the ventricular rate of AF were measured in the following statuses： baseline,vagosympathetic trunk stimulation（VTS）,LSPV-FP ablation,and VTS post LSPV-FP ablation.Results At baseline status,stimulation of the left or right vagosympathetic trunks significantly shortened the ERP of atrial（[84.44±29.50] ms vs [129.7±15.83] ms,[85.42±26.11] ms vs [129.7±15.83] ms,P0.05）,increased the dERP of atrial（[71.67±14.03] ms vs [34.17±18.32] ms,[57.5±24.17] ms vs [34.17±18.32] ms,P0.05）,the difference of ERP between proximal and distal of LSPV（P0.05）,AF inducibility（[5.33±1.231] times vs [0.75±0.96] times,[4.67±1.155] times vs [0.75±0.96] times,P0.05）,and deceased the ventricular rate of AF（[143.6±22.42] beats/min vs [226.3±28.50] beats/min,[146.4±30.72] times/min vs [226.3±28.50] times/min,P0.05）.LSPV-FP ablation significantly attenuated all the above electrophysiological changes induced by left VTS（P0.05）,but showed no effects on those induced by right VTS.Conclusion Left vagosympathetic trunk plays an important role in the development and maintenance of AF partially through LSPV-FP.