Universality in Cardiac Dynamics

Cardiac dynamics displays universal features that stem from similarities in the underlying molecules and structures in the hearts of different species. But the universality can also be considered from the context of nonlinear dynamics. Nonlinear dynamical processes of wave initiation, wave propagation and wave collision prevail over diverse organisms and experimental preparations. Concepts such as period-doubling bifurcations, Cantor sets, and circle maps arise naturally. Application of these concepts provides a physical perspective to the classification of cardiac arrhythmias by cardiologists. Determining the factors that facilitate or impede the persistence of cardiac arrhythmias offer potential directions for improving therapy. I will illustrate these ideas with examples derived from theory, experiment and clinical data with emphasis on paroxysmal rhythms that start and stop suddenly. I will mention several different cardiac arrhythmias including "palpitations", heart block, atrial fibrillation, ventricular tachycardia. The talk may be personally relevant if you (or a close friend or relative) have experienced one of these common arrhythmias.