鸡胚心脏心电位场电势分布的研究

Potential distribution of electrocardiac field around chick embryonic heart

目的探讨心电位场电势分布的本质。方法在电导率不同的3种液态媒质中,将参比点置于远离心电场源的近零电位处,分别采集60个5日龄鸡胚心脏2组相反方向上若干离场源不同距离的测试点的心电图。结果在2种电导率不同的液态媒质中,4个测试方向上所有采取点都记录到以正波为主的心电图;相同媒质相反方向相同距离点上记录的正立心电图,其R(r)波的振幅无统计学差异(P>0.05)。结论排除了导联参比点对心电标测的影响,以及多腔室壁厚薄的纷扰,心电位场电势一致向外的分布方式,表明心脏电位场不是偶极场,而可能是拟球状面分布的类单源场。

Objective To explore the essential features of the potential distribution of electrocardiac field.Methods The ECGs of 60 hearts of 5-day chick embryos were immersed in normal saline solution ordistilled waterand theirdifferent conductivities were recorded at 5 points at different distances in 4 directions perpendicular to each other.Comparison of the form and amplitude of ECGs was made betweenevery two points with the same distance to the heart in 2 opposite directions to determine the potential distributionof the electrocardiac fieldof the one-chamberedheart.Results The ECGs recordedatevery 2 points in 2 opposite directions withthe same distance to the heartimmersedin the same liquid medium were both upperstanding,with no significant different between theiramplitude of R（r） wave（P〉0.05）.Conclusion The uniform outward potential distribution of the electrocardiac field might not represent the form of depolarization but that of sphere-like and single-source when the influence of differentreference points andthickness of differentchamberwalls uponmapping of body surface is excluded.