2017 Volume 57 Issue 4 Pages 191-195
Spiral waves are often observed in wide variety of reaction-diffusion systems. Those in cardiac tissues are important since they are related to serious disease that threatens human lives, such as atrial and ventricular fibrillation. We consider the unpinning of spiral waves around two types of defects using high-frequency pacing. The defects are classified into two kinds, i.e, that without any diffusive interaction with the environment, and that with diffusive interaction. We found that the threshold frequency is lower for the defect with diffusive interaction than for the one without it.