Smart transmission systems have introduced new possibilities of using topology control process for increasing power system dynamic security. Nowadays, in short term analysis, transmission topology is often treated as static and network reconfiguration is performed only for optimizing power flows and market performance. Modern technological infrastructure have enabled fast communication between power system elements. In this scenario, it is foreseeable that topology control can be exploited in real-time as the last resource for avoiding system collapse. In this paper, a dynamic corrective control strategy based on line switching technique is presented. In particular, the proposed method is based on an algorithm that allows to identify transmission lines that should be switched on/off during transients and the time when the corrective action has to be applied in order to guarantee system stability. The feasibility of this approach is demonstrated through simulations on a detailed representation of the Italian transmission network.