The monophasic action potential (MAP) is a near replica of the transmembrane potential recorded when an electrode is pushed firmly against cardiac tissue. Despite its many practical uses, the mechanism of MAP signal generation and the reason it is so different from unipolar recordings are not completely known and are a matter of controversy. In this work, we describe a method to simulate realistic MAP and intermediate forms, which are multiphasic electrograms different from an ideal MAP. The key ideas of our method are the formation of compressed zones and junctional spaces-regions of the extracellular and bath or blood pool directly in contact with electrodes that exhibit a pressure-induced reduction in electrical conductivity-and the presence of a complex network of passive components that acts as a high-pass filter to distort and attenuate the signal that reaches the recording amplifier. The network is formed by the interaction between the passive tissue properties and the double-layer capacitance of electrodes. The MAP and intermediate forms reside on a continuum of signals, which can be generated by the change of the model parameters. Our model helps to decipher the mechanisms of signal generation and can lead to a better design for electrodes, recording amplifiers, and experimental setups.

中文翻译：

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单相动作电位和中间形式的产生

单相动作电位 (MAP) 是将电极牢固推向心脏组织时记录的跨膜电位的近似复制品。尽管有许多实际用途，但 MAP 信号产生的机制以及它与单极记录如此不同的原因尚不完全清楚，并且存在争议。在这项工作中，我们描述了一种模拟真实 MAP 和中间形式的方法，它们是与理想 MAP 不同的多相电图。我们方法的关键思想是压缩区域和连接空间的形成 - 细胞外和浴池或血池的区域直接与电极接触，这些电极表现出压力诱导的电导率降低 - 以及存在复杂的被动网络充当高通滤波器的组件，使到达录音放大器的信号失真和衰减。该网络是由被动组织特性和电极的双层电容之间的相互作用形成的。MAP 和中间形式驻留在信号的连续体上，可以通过模型参数的变化生成。我们的模型有助于破译信号产生的机制，并可以为电极、记录放大器和实验装置带来更好的设计。