The Combined Effect of Myocardial Infarction and Ischemia on Excitation Wave Propagation in Ventricular Tissue

Aims: Previous studies have shown that the infarction and ischemia of cardiac tissue are strongly correlated with incidence of atrial and ventricular tachyarrhythmias. However, so far the combined effect of myocardial infarction and ischemia on the genesis of cardiac arrhythmias has not been fully understood. Therefore, this study aimed to investigate how the coexistence of myocardial infarction and ischemia alters excitation wave propagation.Methods: The electrophysiology remodeling under ischemia condition was mimicked based on experimental data and incorporated into TP06 model. Using the constructed 2D and 3D models, we simulated the excitation wave conduction in ventricular tissue under five different conditions: normal, myocardial ischemia under three levels, and myocardial infarction conditions.Results: Simulation results showed that the conduction velocity and rotor tracks are different in the normal, infarcted and ischemic conditions. In addition, reentry waves are observed in myocardial infarction with the ischemic condition in 2D and 3D models.Conclusion: Simulation results demonstrate that the coaction of myocardial infarction and ischemia areas increases spatial electrical heterogeneity of ventricular tissue, which may enhance the pro-arrhythmogenic effect.