Computer modeling of cardiac conduction system for arrhythmia research and implantable device testing

房室结（AVN）被认为是一个“黑匣子”，其双重通路的功能仍然存在争议，尚未完全理解。我们在Aliev-Panfilov双变量心肌细胞模型的基础上开发了一种紧凑，计算轻量级的多功能兔AVN模型。一维AVN模型包括快速和慢速通路，窦房结原发起搏和慢速通路辅助起搏。我们实现了模型细胞之间的不对称耦合，以获得AVN的方向依赖的传导特性，以及细胞间耦合和细胞耐火度的梯度。AVN模型显示了广泛的功能，包括正常窦性心律、AVN自动性、心房颤动和心房扑动期间高速率心房节律的过滤、方向依赖特性，以及对照病例和快慢路径消融病例中真实的顺行和逆行传导曲线。此外，该模型还附有AVN中导电的可视化，以梯形图的形式揭示了快、慢路径之间的相互作用。为了验证该模型的有效性，我们将仿真结果与现有的实验数据进行了比较。所提出的模型既可以作为一个独立的模块，也可以作为复杂的3D心房或整个心脏模拟系统的一部分。研究结果发表在《Frontiers in Physiology》杂志上（影响因子4.755），MATLAB源代码被放置在一个公共存储库中。

The atrioventricular node (AVN) is considered a ”black box”, and the functioning of its dual pathways remains controversial and not fully understood. We have developed a compact, computationally lightweight multi-functional rabbit AVN model based on the Aliev-Panfilov two-variable cardiac cell model. The 1D AVN model includes fast and slow pathways, primary pacemaking in the sinoatrial node, and subsidiary pacemaking in the slow pathway.We implemented the asymmetry of coupling between model cells to obtain the direction-dependent conduction properties of the AVN, together with gradients of intercellular coupling and cell refractoriness. The AVN model demonstrates broad functionality, including normal sinus rhythm, AVN automaticity, filtering of high-rate atrial rhythms during atrial fibrillation and atrial flutter, direction-dependent properties, and realistic anterograde and retrograde conduction curves in the control case and the cases of fast and slow pathway ablation. In addition, the model is accompanied by a visualization of electrical conduction in the AVN, revealing the interaction between fast and slow pathways in the form of ladder diagrams. To show the validity of the proposed model, we compare the simulation results with the available experimental data.The proposed model can be used both as a stand-alone module and as a part of complex 3D atrial or whole heart simulation systems. The results were published in the journal "Frontiers in Physiology" (impact factor 4.755), and the MATLAB source code was placed in a public repository.