Analysis of the Use of the BPS Model to Simulate Ischemia-induced Hyperkalemia

This study is aimed to test the ability of Bartolucci-Passini-Severi (BPS) model to reproduce the ischemia-induced hyperkalemia, a characteristic feature of the acutely ischemic heart disease. The BPS model is an action potential model of ventricular cardiomyocytes, which correctly reproduces the physiological APD-[Ca2+]e dependence. The simulations consisted of a 30-minutes progressive ischemic period on an isolated cardiomyocyte. In the simulations hyperkalemia was monitored alongside other variables, including ionic currents, potassium fluxes and concentrations. The simulations revealed that, from the onset of ischemia till the 4.4th minute post-occlusion, the extracellular potassium time course is in agreement with other models. However, after this time point the model shows some discrepancies compared to experimental values. The results demonstrated that at this point the sarcoplasmic calcium release suddenly interrupts which could be related to the failure of opening and closing gates of Ryanodine receptors (RyR).