正向低频串脉冲纠正逆向胃电刺激诱发的胃窦胃电过速

Forward Train Pulses with Low Frequency Normalize Artificial Ectopic Tachygastria Induced by Retrograde Antral Electrical Stimulation

背景:胃电过速常由胃窦的异位起搏点引起。明确正向低频串脉冲对人工异位起搏点诱发的胃电过速的纠正作用及其相关参数对于胃电起搏的治疗应用具有重要指导意义。目的:测定低频串脉冲正向胃电刺激(FGES)完全控制高频长脉冲逆向胃电刺激(RGES)模拟异位起搏点诱发的胃电过速的最小刺激能量。方法:于比格犬胃大弯浆膜层植入4对电极,从CH4导联输入高频长脉冲RGES诱发胃电过速,刺激参数:0.3mA,300ms,9cpm(次/min)。10min后,在持续给予RGES的同时从CH1导联输入不同振幅的低频串脉冲FGES,以获得完全控制胃慢波的最小刺激能量。记录胃慢波和消化不良症状。结果:低频串脉冲FGES完全控制高频长脉冲RGES诱发的胃电紊乱所需的最小刺激能量为(149.35±50.66)smA2。与基线胃慢波相比,RGES诱发胃电过速显著增多(55.4%±25.1%对2.1%±1.1%,P=0.037),而FGES可纠正RGES诱发的胃电过速,使之恢复至基线水平。胃慢波基线期、RGES期间和FGES+RGES期间实验犬消化不良症状无明显差异。结论:正向低频串脉冲能纠正由逆向高频长脉冲模拟异位起搏点诱发的胃窦胃电过速,并改善由此降低的胃动力。

Background： Tachygastria is usually produced by antral ectopic pacemaker. It has important guiding significance for further application of gastric pacing to recognize the effect of forward train pulses with low frequency on tachygastria generated by artificial ectopic pacemaker and its related electrical stimulating parameters. Aims： To explore the minimum energy of forward train pulses with low frequency to entrain tachygastria induced by artificial ectopic pacemaker using retrograde long pulses at tachygastrial frequency. Methods： Beagles implanted with four pairs of electrodes along the greater curvature of stomach into sera were applied with retrograde gastric electrical stimulation （RGES） and forward gastric electrical stimulation （FGES）. Long-pulse RGES with high frequency including a series of fixed stimulating parameters, 0.3 mA, 300 ms, 9 cpm, was kept on applying to produce substantial tachygastria. In contrast to RGES, FGES was performed with low frequency train pulses 10 minutes after the beginning of RGES, whose amplitude would be increased stepwise until the tachygastria induced by RGES was completely entrained. Gastric slow waves and animal dyspeptic symptoms were recorded. Results： The minimum energy, （149.35 ±50.66） smA^2 of train-pulse FGES could completely entrain artificial ectopic tachygastria induced by long-pulse RGES. RGES significantly increased tachygastria from 2.1%± 1.1% at baseline to 55.4%±25.1% （P=0.037）, and FGES could normalize the tachygastria induced by RGES. Either RGES or FGES had not seen noticeable dyspeptic symptoms. Conclusions： Train-pulse FGES can normalize the artificial ectopic tachygastria induced by long-pulse antral RGES as well as improve the RGES-induced gastric hypomotility.