A computer model of reflection induced by early afterdepolarizations in ventricular tissue

A computer model has been developed in which reflection was observed. Reflection is a type of reentry in a one-dimensional structure of cardiac cells. The model consists of two segments of ventricular tissue partially coupled by a coupling resistance (R) and it was used to study conditions that provoke the development of EADs, and the generation of reflection and ectopic activity. In the present study, EADs were induced in one segment by enhancing ICaL current and decreasing IKr and IKS currents. The other segment was maintained under normal physiological conditions. The results suggest that ectopic activity in a zone of myocardium could appear due to the reflection induced by EADs generated in neighboring tissue zones. The coupling between areas and the blocked factor of the two components of the delayed rectifier K⁺ current (I_Kr and I_Ks ), have a great influence. The results suggest that a partial coupling between segments and severe conditions in the abnormal segment increase the likelihood of both the ectopic activity and the triggered activity