Biomedical Engineering Reference
In-Depth Information
3.3
CARDIAC OSCILLATIONS AND
ARRHYTHMIA ANALYSIS
Leon Glass
Isadore Rosenfeld Chair in Cardiology and
Department of Physiology, McGill University,
Montreal, Quebec
In current medical practice, the diagnosis and treatment of cardiac arrhythmias in people
is carried out without mathematical analysis of the underlying mechanisms of the under-
lying rhythm. In this article I describe how nonlinear dynamics is being used to formulate
mathematical models of cardiac arrhythmias, and to demonstrate the ways the mathemat-
ics can be used to predict the changes in rhythms that occur as physiological parameters
vary. In spatially heterogeneous cardiac tissue culture, a number of different patterns of
spatiotemporal activity can be found, including propagating plane waves, rotating spiral
waves, and spiral waves that spontaneously initiate and terminate. These paroxysmal pat-
terns are similar to the paroxysmal rhythms observed during cardiac arrhythmias in peo-
ple. Mathematical analyses of cardiac arrhythmias can be used to determine automatically
if certain arrhythmias, such as atrial fibrillation, are present in individuals. Attempts are
also underway to develop new methods to analyze normal and abnormal cardiac activity
in patients to better assess the risk of fatal arrhythmias before they occur.
1.
INTRODUCTION
Over the course of our lives, our hearts will beat approximately 2 + 10
9
times. Although we have the impression that the rhythm is quite regular, there is
Address correspondence to: Leon Glass, Department of Physiology, 3655 Promenade Sir William
Osler, McGill University, Montreal, Quebec, Canada H3G 1Y6 (glass@cnd.mcgill.ca)
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