Electrophysiological Changes In Left Atrium And Pulmonary Vein In Goat Model Of Persistent Atrial Fibrillation

Backgroud Atrial fibrillation (AF) induce electrical remodeling in atrium and in pulmonary veins (PVs). But the relative importance of electrophysiological remodeling in PV versus left atrium (LA) in the development of persist AF is unknown. The aim of this study was to compare the changes of electrophysiological parameters in PV and LA in goat model of persistent AF. Methods Twelve female goats were instrumented with epicardial electrodes patches on LA and left superior pulmonary vein (LSPV). AF was induced and maintained by atrial stimulator with frequency of 50 Hz, duration of 1 second and 2 seconds intermission. Before the onset of stimulation and after the stimulation lasted for 6 h, 12 h, 24 h and every other 24 h, the stimulator was disconnected.The effective refractory period (ERP) and the inducibility of AF were measured in LSPV and LA.Results (1) Persistent AF could be induced in the 9 goats within 5-14 days. In baseline, there was no significant difference in ERP between LSPV and LA. With the perpetuation of AF, ERP shortened in both LA and LSPV (P<0.05). But there was no significant difference between LSPV and LA;(2) Before AF inducement, the (AERP300- AERP₂₀₀)/100 ms in LSPV was 0.22±0.06. With the perpetuation of AF, the rate adaptability decreased gradually (P<0.05). It did the same change in LA (P>0.05);(3) The inducibility of AF in LSPV and LA increased gradually (P<0.05). It showed no significant difference of AF inducibility between LSPV and LA.Conclusion The electrophysiological changes in LSPV are comparable to those in LA in the process of electrical remodeling. It shows no significant difference in the inducement of AF between LSPV and LA in this model.