Pacemaking function of two simplified cell models

Abstract

Simplified nonlinear models of biological cells are widely used in computational electrophysiology. The models reproduce qualitatively many of the characteristics of various organs, such as the heart, brain, and intestine. In contrast to complex cellular ion-channel models, the simplified models usually contain a small number of variables and parameters, which facilitates nonlinear analysis and reduces computational load. In this paper, we consider pacemaking variants of the Aliev-Panfilov and Corrado two-variable excitable cell models. We conducted a numerical simulation study of these models and investigated the main nonlinear dynamic features of both isolated cells and 1D coupled pacemaker-excitable systems. Simulations of the 2D sinoatrial node and 3D intestine tissue as application examples of combined pacemaker-excitable systems demonstrated results similar to obtained previously. The uniform formulation for the conventional excitable cell models and proposed pacemaker models allows a convenient and easy implementation for the construction of personalized physiological models, inverse tissue modeling, and development of real-time simulation systems for various organs that contain both pacemaker and excitable cells.

A compact multi-functional model of the rabbit atrioventricular node with dual pathways

“…They are described by the same A-P model with a negative coefficient a 1 . The oscillating (pacemaking) properties of the A-P model were considered recently (Ryzhii and Ryzhii, 2022).…”

“…That substitutes a significant advantage of the cardiac A-P model over the FitzHugh-Nagumo and modified Van der Pol models and their combinations, used in the modeling of the simplified cardiac conduction system (Podziemski and Żebrowski, 2013;Ryzhii and Ryzhii, 2014), due to the absence of the quiescent state in the modified Van der Pol model and the absence of well-defined threshold potential in both FitzHugh-Nagumo and modified Van der Pol models. Also, close values of the minimal diastolic potential of both non-pacemaking and pacemaking A-P model cells allow the driving of a relatively big number of non-pacemaking cells by a single pacemaking A-P model cell (Ryzhii and Ryzhii, 2022).…”

Atrioventricular nodal reentrant tachycardia onset, sustainability, and spontaneous termination in rabbit atrioventricular node model with autonomic nervous system control

“…Parameters ϵ 0 , a 1 , a 2 , µ 1 , and µ 2 determine the conduction characteristics of tissue, a 1 > 0 represent the excitation threshold of quiescent excitable cells, while a 1 < 0 sets the intrinsic oscillation frequency of the pacemaking cells (grayshaded in Fig. 1) [14]. The intercellular coupling terms…”

A compact multifunctional model of the rabbit atrioventricular node with dual pathways

“…That substitutes a significant advantage of the cardiac APm over the FitzHugh-Nagumo and modified Van der Pol models and their combinations, used in the modeling of the simplified cardiac conduction system 13, 30 , due to the absence of the quiescent state in the modified Van der Pol model and the absence of well-defined threshold potential in both FitzHugh-Nagumo and modified Van der Pol models. Also, close values of the minimal diastolic potential of both non-pacemaking and pacemaking APm cells allow the driving of a relatively big number of non-pacemaking cells by a single pacemaking APm cell 28 .…”

“…They are described by the same APm with a negative coefficient a 1 . The oscillating (pacemaking) properties of the APm were considered recently 28 . Implementing the oscillating APm cells simplifies the model description, providing easy control of intrinsic oscillation frequency and reliable overdrive suppression 29 .…”