In Silico Investigation of The Impact of the Ventricular Filling Heterogeneity on the Electrical Field Propagation Using a Patient-Specific Model

This study investigates the influence of the ventricular blood pool (BP) on simulations of cardiac electrical activation using a patient-specific anatomical model and two computational approaches: the bidomain (BD) and pseudo-bidomain (P-BD) models. The simulations were performed for a 17-year-old patient with premature ventricular contractions (PVCs) originating near the His bundle. Both BD and P-BD models were tested with and without the inclusion of the BP. Local activation times (LAT) and body surface potentials (BSP) were analyzed to evaluate the effect of BP inclusion across different model configurations. The results showed that LAT was nearly identical across all four model configurations, with correlation coefficients above 0.99 and RMSE values below 1.39%. BSP, however, were more sensitive to both the choice of model and the inclusion of BP, particularly in signal amplitude, with maximum RMSE values reaching 8.194%. Despite these amplitude differences, the overall waveform morphology remained almost unchanged. These findings suggest that the BP has a negligible effect on LAT and signal morphology but can influence signal amplitude. Therefore, the computationally less demanding P-BD model without BP may be sufficient for simulating focal activation patterns. Further simulations involving more complex propagation patterns are needed to validate the general applicability of this approach.