Oscillators competition.
Application to cardiac arrhythmias.
The
particular class of cardiac arrhythmias
called pure ventricular parasystole is produced
due to the appearance of an ectopic focus,
located in the ventricles, which is firing
with a larger and more irregular period
than the normal sinoatrial node.The presence
of abnormal beats, together with the normal
sinus beats, is featured in characteristic
electrocardiograms.
We
study the interaction between two independent
nonlinear oscillators competing through
a passive (excitable) element. The first
oscillator acts as a normal pacemaker for
the neutral element. The second oscillator,
though unable to make the excitable unit
to beat, is assumed to trigger its premature
activation leading to the occasional suppression
of firing. The outcome signal, recorded
from the excitable unit, is thus reminiscent
of the pacemaker rhythm but interspersed
with blocked beats. Firing errors are registered
and the analyzed recordings display different
dynamical patterns as the basic observables
of both oscillators (periods) are varied.
- Publications:
Exported
oscillator competition: A concept to
analyze complex rhythms,
A.M. Lacasta, J.M. Sancho and
F. Sagues,
Phys. Rev. E 73, 016206 (2006).
|
