%0 Journal Article
%T Line-Defect Patterns of Unstable Spiral Waves in Cardiac Tissue
%A Juan G. Restrepo
%A Alain Karma
%J Quantitative Biology
%D 2008
%I arXiv
%R 10.1103/PhysRevE.79.030906
%X Spiral wave propagation in period-2 excitable media is often accompanied by line-defects, the locus of points with period-1 oscillations. Here we investigate spiral line-defects in cardiac tissue where period-2 behavior has a known arrhythmogenic role. We find that the number of line defects, which is constrained to be an odd integer, is three for a freely rotating spiral, with and without meander, but one for a spiral anchored around a fixed heterogeneity. We interpret analytically this finding using a simple theory where spiral wave unstable modes with different numbers of line-defects correspond to quantized solutions of a Helmholtz equation. Furthermore, the slow inward rotation of spiral line-defects is described in different regimes.
%U http://arxiv.org/abs/0806.3489v1