George
Washington University Medical Center
In a pursuit of a spiral
waves
Kostya
Agladze
Abstract: Excitation waves are known
to play an important role in the
self-organization of a wide variety of nonlinear media, including
biological,
chemical, and ecological systems. An important prerequisite for these
waves is
the coupling of local excitable kinetics with diffusion transport. One
of the
most intriguing examples of dynamic structures in excitable systems is
rotating
spiral waves. Although
spiral waves were discovered in a variety of active media,
their study was in major part inspired by the relevance of this topic
to the
functioning of heart in the normal and pathological conditions. While
during
last three decades plenty of information about dynamics of rotating
waves was
accumulated from the experiments on model systems and computer
simulations,
most of it was not justified for the cardiac tissue for an apparent
reason of
difficulty of direct observations. Thus, understanding of spiral wave
origination and termination, as well as many approaches to control
spiral waves
(such as pacing, for instance) remain based on theoretical concepts and
data
obtained from computer simulations. Recent success in development of an
experimental model based on the cardiomyocyte layers and in methods of
visualization of excitation waves with the aid of potential sensitive
and Ca++
sensitive dyes creates an avenue for new studies with the long term
goals to
develop clinically applicable methods for controlling and terminating
rotating
waves in cardiac tissue