In this paper, a scheme of spatial perturbation is introduced into a class of excitable media, which are described by two-dimensional partial-differential equation models. Inertial acentric force (or centripetal force), which is generated by circumgyrating the whole system vs. a right axis, is used to disturb the system. The whole system becomes homogeneous as soon as the spatial perturbation is imposed on even when the noise is in consideration. The principle of this scheme is confirmed based on the theory of hopf bifurcation and numerical simulation.