title: Elimination of a spiral wave pinned at an obstacle by a train of plane waves: Effect of diffusion between obstacles and surrounding media.
abstract: In excitable media such as cardiac tissue and Belousov-Zhabotinsky reaction medium, spiral waves tend to anchor (pin) to local heterogeneities. In general, such pinned waves are difficult to eliminate and may progress to spatio-temporal chaos. Heterogeneities can be classified as either the absence or presence of diffusive interaction with the surrounding medium. In this study, we investigated the difference in the unpinning of spiral waves from obstacles with and without diffusive interaction, and found a profound difference. The pacing period required for unpinning at fixed obstacle size is larger in case of diffusive obstacles. Further, we deduced a generic theoretical framework that can predict the minimal unpinning period. Our results explain the difference in pacing periods between for the obstacles with and without diffusive interaction, and the difference is interpreted in terms of the local decrease of spiral wave velocity close to the obstacle boundary caused in the case of diffusive interaction.
authors.affiliation: Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Masanobu
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto 606-8501, Japan.
authors.forename: Marcel
authors.initials: M
authors.lastname: Hörning
authors.affiliation: Department of Physics, Graduate School of Science, Chiba University, Chiba 263-8522, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kitahata
authors.affiliation: Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto 610-0394, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Yoshikawa
mesh_terms: D000401:Aircraft; D017711:Nonlinear Dynamics; D011890:Railroads; D013016:Sound