摘要
目的 探索可逆性脉冲电场(RPEF)是否能暂时抑制电传导,为临床提供一种分析定位快速性心律失常峡部从而实现精准消融的新方法.方法 将6只拉布拉多健康犬插管麻醉后,分别对实验犬的左心房和右心房进行RPEF消融.从RPEF消融开始至消融后5 min连续测量双极电图,选择消融前后电位电图,进行电图振幅分析.评估RPEF消融前后脉冲宽度为2 ms的起搏阈值.实验犬安乐死后,取离体心脏RPEF消融部位进行电镜检查.结果 6只实验犬的基线电图振幅为7.76(6.39,10.70)mV,应用RPEF消融后电图振幅降至1.93(1.22,3.90)mV,减少71.7％(53.7％,83.8％).在观察期内,振幅逐渐恢复.分别观察8个RPEF消融部位[分别位于左心房后壁(n=4)、右心房游离壁(n=2)、右心房间隔(n=1)和右心耳根部(n=1)]的电图5 min,电图振幅为5.93(5.26,7.55)mV,恢复到基线的75.6％(72.4％,87.3％).电解剖标测未显示RPEF消融部位有任何双极低电压(＜0.1 mV)区域.起搏阈值消融开始前为1.0(1.0,1.2)mA,消融后即刻为3.0(2.0,5.8)mA,消融后5 min恢复至2.0(1.3,3.0)mA.实验犬尸检时,在2个明显的射频损伤部位之间观察到一个大体完好的心肌区域,未见损伤.组织学显示有轻中度退行性变,无坏死性改变.结论 RPEF能暂时抑制实验犬心肌组织电传导,引起可逆性心肌损伤.RPEF的这一特性,为定位心律失常关键峡部后再进行不可逆性精准消融提供了依据.
Abstract
Objective To explore the effect of reversible pulsed electric fields(RPEF)on temporarily inhibition of electrical conduction,and to provide a novel location analysis for tachyarrhythmia isthmus to achieve precise ablation.Methods Six healthy Labrador dogs were intubated and anesthetized.RPEF energy was delivered to the left atria and right atria in dogs.The electrogram was measured continuously from the beginning of RPEF ablation to 5 min after ablation.Electrograms before and after ablation were selected for amplitude analysis.Pacing threshold at 2 ms pulse width was evaluated.After euthanasia,the RPEF ablation regions were removed from isolated heart for electron microscopy.Results The electrogram amplitude at baseline was 7.76(6.39,10.70)mV and diminished to 1.93(1.22,3.90)mV after the RPEF ablation,translating to a reduction of 71.7％(53.7％,83.8％).There was a gradual recovery of the amplitude over the observation period.Eight RPEF ablation electrograms[left atrium posterior wall(n=4),right atrium free wall(n=2),right atrial septum(n=1)and the root of right atrial appendage(n=1),respectively]were observed after 5 min and the amplitude was 5.93(5.26,7.55)mV,recovered to 75.6％(72.4％,87.3％)of baseline.The pacing threshold was 1.0(1.0,1.2)mA before ablation,3.0(2.0,5.8)mA immediately after ablation and recovered to 2.0(1.3,3.0)mA 5 minutes after ablation.Electroanatomic mapping did not show any areas of low bipolar voltage(＜0.1 mV)at the RPEF ablation locations.At necropsy,a broadly intact region of myocardium with no lesion was observed between the 2 apparent sites of radiofrequency lesion.Histology showed mild to moderate degeneration and no necrotizing changes.Conclusions RPEF can be applied to transiently block electrical conduction in myocardial tissues and cause reversible myocardial lesion.Irreversible ablation should be performed when the critical isthmus of arrhythmia is identified,so as to achieve precise ablation.
基金项目
北京大学首钢医院首颐医疗科技发展基金(SGYYQ202109)
NETL
NSTL
万方数据