Computer modelling of cardiac repolarisation and recovery processes

A computer model simulating both excitation and recovery processes within a block of heart muscle tissue has been developed. It incorporates blocks of tissue consisting of several thousand elements and introduces phenomena which are omitted in other heart models. These include the specific shapes of action potential curve corresponding to excitation of cells which have not been fully recovered. Results of simulation studies are presented in the form of three-lead orthogonal electrocardiograms (ECGs). Another model was used to reproduce the electronic interactions between neighboring cells during recovery phases. It also improves the concept of the modeled excitation and treats the depolarization as an self-initiating process depending only on membrane voltage between coupled cells. Both models have been used in various computational series. The results presented include models of destabilizing the tissue due to fast sequential stimulation models of repolarization changes in ischemia and infarction, and models of ´reflection´ mechanisms.<>