微电极阵列芯片技术研究48h房颤犬左、右心耳电生理特性

目的应用微电极阵列芯片（microelectrode arrays chip,MEA）技术评价48 h房颤（atrial fibrillation,AF）犬左、右心耳（LAA、RAA）的电生理特性。方法随意来源犬12只,以600次/分起搏右心房建立AF模型,分为48 h AF组（n=6）和对照组（n=6）。造模成功后迅速开胸剪取LAA、RAA,置于盛有台式液的MEA中,分别记录AF组及对照组LAA、RAA场电位（field action potential,FAP）形态、振幅、放电频率及激动传导情况。结果 AF组LAA、RAA组织FAP节律绝对不齐,LAA（185.22±25.62）次/分,较对照组（156.44±8.88）次/分增加15.67%（P〈0.01）,RAA（102.39±16）次/分,较对照组（156.44±8.88）次/分减慢34.62%（P〈0.01）。48 h AF组LAA组织电压（458.33±26.73）μV较对照组（740.55±18.93）μV降低38.11%（P〈0.01）,RAA（504.83±39.93）μV较对照组（840.56±18.93）μV明显降低（P〈0.01）,48 h房颤组LAA组织FAP时程（45.28±8.59）ms较对照组（70.77±6.98）ms缩短15 ms（P〈0.01）。RAA（61.78±7.1）ms较对照组（75.83±7.63）ms缩短14 ms（P〈0.01）。48 h AF组LAA、RAA FAP传导异质性增加。结论应用MEA技术可反映心肌组织片场电位电生理特性,48 h AF后LAA放电频率增加,频率绝对不齐,LAA、RAA电压降低,场电位时程延长。

Electrophysiological characteristics of the right and left atrial appendages in 48-h atrial fibrillation canine detected by microelectrode arrays chip

Objective To explore the electrophysiological characteristics of right atrial appendage （RAA） and left atrial appendage （LAA） in 48-h atrial fibrillation （AF） canine detected by microeleetrode array （MEA） chip tech- nique. Methods Twelve adult healthy mongrel canine were randomly divided into two groups：48-h pacing group and con- trol group. The 48-h AF model was established by rapid pacing the right atrium. The RAA and LAA were quickly removed and immersed into Tyrode＇ s solution in MEA chip dish. The morphology, duration, voltage, discharge frequency and con- duction of field action potential were recorded. Results In the AF group, the rhythms of LAA and RAA tissue field poten- tial were irregular. The frequency of LAA （ 185.22 ± 25.62 beats/min） was increased by 15.67% （ 156. 44 ± 8.88 beats/ min） （ P 〈 0. 01 ）, and the frequency of RAA （ 102.39±16 beats/min） was decreased by 34. 62% than that in the control group （156. 44 ± 8.88 beats/min） （P 〈 0. O1 ）. The voltages of LAA （458.33 ± 26.73 ） μV and RAA （504. 83 ±39.93 ）μV were decreased than those of the control group （740. 55 ± 18.93）μV and （840. 56 ±18.93 ）μV, respectively, （P 〈 0. 01 ）. The durations of field potential of LAA （45.28± 8.59） ms and RAA （61.78 ± 7.1 ） ms were significantly shortened than those of the control group （70. 77 ±6. 98）ms （P 〈 0. 01 ）. The electric impulse presented anisotropic alteration. Conclusions MEA is a sensitive, long-lasting and stable technique, and local tissue action potential can be used to assess the electrophysiological characteristics of field potential in animal heart slices using multiple-channel recording mapping sys- tem. The discharge frequency of left atrial appendage is increased and frequency irregularity occurs after 48 h atrial fibrilla- tion, the voltage of field potential is decreased in the atrial appendage, and the field potential duration is prolonged.