Development of Simplified Model of Atrioventricular Node with Dual Pathway

Pacemaking function of two simplified cell models

“…Single-cell pacemaker dynamics Absence of the undershoot of the action potential amplitude in the pAP and pCN models (in contrast to the FHN model [5,6]) makes them specifically suitable for utilization as secondary pacemakers and in the cardiac simulation systems with limited number of elements, similar to proposed in the works [38,39,52]. For the pCN model, the frequency and, in particular, DI/APD ratios depend also on the time constants τ in , τ out ,τ open , and τ close .…”

“…The phase portraits and nullclines of excitable and pacemaking model variants are presented in The absence of undershoot of the action potential amplitude in the pAP and pCN models (in contrast to the FHN model [9,10]) makes them specifically suitable for utilization as secondary pacemakers and in the cardiac simulation systems with a limited number of elements, similar to proposed in the works [44][45][46]. Both models demonstrated notably wide ranges of intrinsic frequencies: 0.007 -7.6 Hz for pAP, 0.14 -14 Hz for pCN, corresponding to about 0.4 -450 and 8.4 -840 counts per minute (cpm), respectively.…”

“…The utilization of the considered pacemaker models can be beneficial for the development of simplified real-time simulation systems (e.g. personalized medicine [24,25] and inverse cardiac modeling [26]), deep learning [37], as well as for medical device testing platforms [38,52].…”

“…When spontaneous oscillation appeared, we determined peak overshoot potential (POP), maximum diastolic potential (MDP), frequency, diastolic interval (DI), and action potential duration (APD) at 90% repolarization for each bifurcation parameter value upon allowing the oscillation activity to stabilize within 20 -50 s. non-integer [55]), apart from the normal case (n = 1) we considered higher (n = 2) and lower (n = 0.5) loads. These load-driving capabilities are essential for real-time simulation systems based on abstracted heart models, where a single pacemaker cell represents a group of ion-channel pacemaker model cells [44,46].…”

“…The above-mentioned models, however, underline the need for simple computationally efficient models, in particular, having a uniform description for pacemaking and excitable cells. These models are essential for abstracted heart models with real-time simulation capabilities, where a single pacemaker cell represents a group of ion-channel pacemaker model cells [44,46].…”