Influence of the Variability of Excitation Parameters on a Rhythm in Parasystole Mathematical Model and in Clinic

  • D. Eidukas Kaunas University of Technology
  • R. Labrencas Kaunas University of Technology
  • I. Grigaliūnienė Kaunas University of Medicine
  • M. Skučas Kaunas University of Medicine
  • R. Lekas Kaunas University of Medicine


The study introduced the possibility of a random variability of Ts and Te (simulated as impulse periods of the “sinus node” and the “ectopic” focus) and Tref (as the refractory period of the excitation medium) in the mathematical model of cardiac parasystole. The influence of the variability of these parameters on the modeled rhythm was estimated. We have found that the increase in the variability of up to 20% only makes the rhythm more disorderly, whereas the character of the rhythm is determined by changes in Tref value. We believe, that the Tref is reliably reflected in Poincare map as the duration of the shortest RR intervals registered in the monitoring ECG of patients with parasystole arrhythmias. This parameter also is therefore useful by the control of the efficiency of antiarrhythmic treatment. Ill. 5, bibl. 7 (in English; summaries in English, Russian and Lithuanian).