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DY: Fachverband Dynamik und Statistische Physik
DY 19: Nonlinear Dynamics of the Heart: Contributed talks to focus session
DY 19.4: Talk
Wednesday, March 28, 2012, 15:45–16:00, MA 001
Dynamical impact of structural heterogeneities in electrically-stimulated cardiac tissue — •Philip Bittihn1, Marcel Hörning2, and Stefan Luther1 — 1Max Planck Institute for Dynamics and Self-Organization, Göttingen, Germany — 2Department of Physics, Graduate School of Science, Kyoto University, Kyoto, Japan
Acute heart rhythm disorders such as fibrillation that underly sudden cardiac death are one of the leading causes of death in the industrialized world. When fibrillation arises, normal rhythm is usually restored using electrical shocks. In the last decade, both experiments and computationally intensive numerical simulations have been aimed at modeling the underlying mechanisms and at the improvement of these control strategies. Here, we theoretically target a basic feature of cardiac tissue that leads to its heterogeneous response to electric fields: its complex geometry. We examine mathematically how the shape of both internal and external tissue boundaries modifies the changes in membrane potential induced by electric fields. The results are confirmed both in cardiomyocyte cell culture experiments and in numerical simulations. Furthermore, we examine numerically how stimulation protocol parameters influence the ability of heterogeneities to act as wave sources. These investigations open the way to a profound theoretical understanding of electric-field stimulation effects in cardiac tissue.