When generating in-silico clinical electrophysiological outputs, such as electrocardiograms (ECGs) and body surface potential maps (BSPMs), mathematical models have relied on single physics, i.e. of the cardiac electrophysiology (EP), neglecting the role of the heart motion. Since the heart is the most powerful source of electrical activity in the human body, its motion dynamically shifts the position of the principal electrical sources in the torso, influencing electrical potential distribution and potentially altering the EP outputs. In this work, we propose a computational model for the simulation of ECGs and BSPMs by coupling a cardiac electromechanical model with a model that simulates the propagation of the EP signal in the torso, thanks to a flexible numerical approach, that simulates the torso domain deformation induced by the myocardial displacement. Our model accounts for the major mechano-electrical feedbacks, along with unidirectional displacement and potential couplings from the heart to the surrounding body. For the numerical discretization, we employ a versatile intergrid transfer operator that allows for the use of different Finite Element spaces to be used in the cardiac and torso domains. Our numerical results are obtained on a realistic 3D biventricular-torso geometry, and cover both cases of sinus rhythm and ventricular tachycardia (VT), solving both the electromechanical-torso model in dynamical domains, and the classical electrophysiology-torso model in static domains. By comparing standard 12-lead ECG and BSPMs, we highlight the non-negligible effects of the myocardial contraction on the EP-outputs, especially in pathological conditions, such as the VT.

翻译：在生成诸如心电图（ECGs）和体表电位图（BSPMs）等计算机模拟临床电生理输出时，数学模型通常依赖于单一物理过程，即心脏电生理（EP），而忽略了心脏运动的作用。由于心脏是人体中电活动最强的源，其运动会动态改变躯干中主要电信号源的位置，从而影响电位分布，并可能改变电生理输出。在本工作中，我们提出了一种通过将心脏电机械模型与模拟躯干中电生理信号传播的模型耦合的计算方法，用于生成ECGs和BSPMs。该耦合得益于一种灵活的数值方法，能够模拟因心肌位移引起的躯干域变形。我们的模型考虑了主要的机械-电反馈机制，以及从心脏到周围组织的单向位移和电位耦合。在数值离散方面，我们采用了一种通用的网格间传递算子，允许在心脏域和躯干域中使用不同的有限元空间。数值结果基于真实的3D双心室-躯干几何结构，涵盖窦性心律和室性心动过速（VT）两种情况，并在动态域中求解电机械-躯干模型，同时在静态域中求解经典电生理-躯干模型。通过比较标准的12导联心电图和体表电位图，我们强调了心肌收缩对电生理输出的不可忽略影响，尤其是在室性心动过速等病理条件下。