Title
Phase response characteristics of sinoatrial node cells
Abstract
In this work, the dynamic response of the sinoatrial node (SAN), the natural pacemaker of the heart, to short external stimuli is investigated using the Zhang et al. model. The model equations are solved twice for the central cell and for the peripheral cell. A short current pulse is applied to reset the spontaneous rhythmic activity of the single sinoatrial node cell. Depending on the stimulus timing either a delay or an advance in the occurrence of next action potential is produced. This resetting behavior is quantified in terms of phase transition curves (PTCs) for short electrical current pulses of varying amplitude which span the whole period. For low stimulus amplitudes the transition from advance to delay is smooth, while at higher amplitudes abrupt changes and discontinuities are observed in PTCs. Such discontinuities reveal critical stimuli, the application of which can result in annihilation of activity in central SAN cells. The detailed analysis of the ionic mechanisms involved in its resetting behavior of sinoatrial node cell models provides new insight into the dynamics and physiology of excitation of the sinoatrial node of the heart.
Year
DOI
Venue
2007
10.1016/j.compbiomed.2005.09.011
Comp. in Bio. and Med.
Keywords
DocType
Volume
Heart,Sinoatrial node,Mathematical models,Cardiac models,Phase resetting,Three-dimensional phase transition curves,Regional differences
Journal
37
Issue
ISSN
Citations 
1
0010-4825
3
PageRank 
References 
Authors
0.87
0
5
Name
Order
Citations
PageRank
Dimitrios G. Tsalikakis130.87
H. G. Zhang230.87
Dimitrios I. Fotiadis3941121.32
George P. Kremmydas430.87
Lampros K. Michalis517721.89