【摘要】 目的研究去自主神经条件下迷走神经对肺静脉不同部位房颤诱发阈值的影响。方法于2004年10月至2005年5月对北京大学人民医院心脏电生理室的10只健康杂种犬进行了电生理实验。所有动物均经切断双侧颈迷走神经干和破坏颈交感神经节,建立犬的去自主神经模型。分别在右心耳(RAA)、左心耳(LAA)、左房(LA)和四支肺静脉的近、中、远段行burst刺激,刺激周长S1S1为80ms,脉宽为0.5ms,在仅改变电压刺激强度的情况下,观察迷走神经对肺静脉不同部位房颤诱发阈值的影响。结果当行双侧颈迷走神经刺激时,在心房及肺静脉的所有部位,房颤诱发阈值均有不同程度的下降,且在4支肺静脉的远段表现为差异有显著性(P<0.05和P<0.01),而阿托品则可消除这种变化。结论对于肺静脉起源的房颤,迷走神经不仅参与房颤的维持,而且也可能是参与其起始的重要诱发因素。更多还原

【Abstract】 Objective To investigate vagal effects on atrial fibrillation(AF)thresholds at different sites of pulmonary veins after autonomic denervation.Methods In 10 mongrel dogs,the cervical vagal trunks were isolated bilaterally and decentralized from Oct 2004 to May 2005.The ansae subclaviae were exposed bilaterally as they exited from the stellate ganglia,doubly ligated,and cut.Local rapid electrical stimulation(S1S1=80 ms,impulse duration 0.5 ms)was performed to right appendage(RAA)、left appendage(LAA)、left atrium(LA)and different sites of 4 pulmonary veins.AF threshold was determined at each site in the baseline state,during bilateral cervical vagal stimulation(VNS,12.5 Hz,impulse duration 0.5 ms,stimulation voltage 5～8 V)and during infusion of atropine.Results During VNS,a lower AF threshold was observed at all sites,especially at distal of 4 pulmonary veins(P<0.05～0.01).There was a raise in the AF threshold as indicated by intravenous infusion of atropine comparing VNS,but there was no significant change in the AF threshold between the baseline and infusion of atropine(P>0.05).Conclusion Vagal nerve not only contributes to the maintenance of AF originating from pulmonary veins,but also greatly promotes the initiation of AF.更多还原