Vagal effects on atrial fibrillation thresholds of pulmonary veins after autonomic denervation / 中国实用内科杂志

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(P0.05).Conclusion Vagal nerve not only contributes to the maintenance of AF originating from pulmonary veins,but also greatly promotes the initiation of AF.