February 21, 2003
Friday - 12:15 pm in Swain East 140
Speaker: Dr. Sima Setayeshgar, Princeton University
Title: Electrical Wave Propagation in the Heart: Dynamics of Scroll Waves in Anisotropic Excitable Media
Abstract:
We consider the asymptotic theory for the dynamics of scroll waves in the presence of rotating anisotropy. A physically relevant system for such dynamics is the left ventricle of the heart, in which the orientation of fibers in successive layers of tissue rotates through the thickness of the ventricle. The "natural" coordinate system for the problem is proposed to be that given by the fiber rotation (rotation of the fast axis of diffusion). For the simple case of a straight filament, we derive a phase equation which is given by the forced Burgers' equation, with forcing associated with the fiber rotation rate. We present approximate analytical solutions for scroll twist, verified by numerics, using a realistic fiber distribution profile. We make connection with earlier numerical experiments and previous analytical work on scroll dynamics in three dimensions.