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Updated: Jun 4, 2026

Microelectrode Array Recording of Sinoatrial Node Firing Rate to Identify Intrinsic Cardiac Pacemaking Defects in Mice
Published on: July 5, 2021
[Analysis of changes in heart rate variability during fast extracardial impulsation in the sinoatrial node]
Abstract:
It is known that fast extracardial impulsation in the sinoatrial node modifies the degree of heart rare variability. The present study presents theoretical and experimental investigation of this effect. Theoretical investigation is based on the mathematical modelling of impulse conduction in the cardiac conduction system. Experimental investigation on dogs revealed quantitative correlations between the frequency of extracardial impulsation in the sinoatrial node and changes of heart rate variability. Computer simulation shows that the mathematical model can account for most principal properties of the heart rate disturbances during fast extracardial impulsation in the sinoatrial node: transitions between different regimens of heart rate dynamics; increase in the delay of atrio-ventricular conduction; Wenkebach's periodicity.
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