一种表现出模拟自发性心房颤动的局部和区域动力学的异质FitzHugh-Nagumo模型
A Heterogeneous FitzHugh-Nagumo Model Exhibiting Local and Regional Dynamics that Mimic Spontaneous Atrial Fibrillation
- West Virginia University Hospitals（西弗吉尼亚大学医院）
- Ohio University（俄亥俄大学）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
该研究通过二维FitzHugh-Nagumo网络模拟，发现健康组织中嵌入的小异质性区域在单次正常兴奋下即可引发并维持心律失常，表现为螺旋波，并可能漂移形成治疗幻影靶点。
AI中文摘要：
我们研究了在模拟心脏组织的状态下，二维FitzHugh-Nagumo振荡器网络。该网络包含具有快速恢复特性的小细胞层和具有慢速恢复特性的相邻细胞层。数值模拟表明，当网络中单个健康波激活时，快恢复细胞与慢恢复细胞之间的边界可以引发类似颤动（fibrillatory-like）的行为。我们讨论了这些结构与心房颤动发作之间可能的联系，旨在增进我们对这一代价高昂疾病的理解和治疗。我们的主要结论是，嵌入健康组织中的小面积异质性受到单次正常兴奋即可引发心律失常，而二维网络随后能够以双回旋曲线和螺旋波的形式维持不规则放电模式。这种情况发生在一个非常简单的可兴奋细胞模型中，我们对该心律失常给出了清晰的机制性描述。该模型说明了心脏组织中异质性增加如何逐步导致先是间歇性、后是持续性的心律失常行为。另一个结论是，问题性放电的中心可能从异质性区域漂移到健康组织中，从而为治疗呈现幻影靶点。
英文摘要：
We study two-dimensional networks of FitzHugh-Nagumo oscillators in regimes that mimic cardiac tissue. The networks include small layers of cells that have fast-recovery characteristics and adjacent layers of cells that have slow-recovery. Numerical simulations show that the boundary between the fast- and slow-recovery cells can initiate fibrillatory-like behavior when activated by a single, healthy wave in the network. We discuss possible connections between these structures and the onset of atrial fibrillation, with the goal of improving our understanding and treatment of this costly condition. Our main conclusion is that a single, normal excitation of small areas of heterogeneity embedded in healthy tissue can initiate arrhythmias and the two dimensional network can then sustain irregular firing patterns in the form of double swirling-back curves and spiral waves. This occurs with a very simple model of excitable cells and we give a clear mechanistic description of the arrhythmia. The model illustrates how increasing heterogeneity in heart tissue can progressively cause first intermittent and then persistent arrhythmic behavior. Another conclusion is that the center of problematic firings can drift away from the heterogeneity into healthy tissue, thus presenting phantom targets for treatment.
