Computational Modeling of Myocardial Thermal lesion Induced by Multi-source Frequency Control RF ablation Method

Abstract

In minimally invasive surgery for atrial fibrillation, radiofrequency (RF) voltage is usually used to ablate cardiac tissue. In this study, a computational modeling of multi-source frequency control RF ablation mode (FcM) was constructed to analyze the characteristics of thermal field and electric field in myocardium. To highlight the relationship between frequency difference and lesion size of ablation, the amplitude and phase angle of voltage in the simulation were fixed at 20 V peak and 0 degree, respectively. Furthermore, the thermal lesion depth, width and continuity produced by FcM and multi-source bipolar ablation mode(BiM) were also compared in this paper. At the electrical boundary condition for creating continuous lesion, the transmural and continuous lesion (long or short) was generated by FcM, whereas BiM did not create transmural lesion. At the electrical boundary condition for creating discrete lesion, FcM was able to create two or one transmural discrete lesion, whereas BiM did not create transmural lesion. Simulation results show that a kind of transmural, continuous, symmetrical lesion shape was generated in atrial tissue using multi-source frequency control RF ablation and the lesion size was larger than BiM at identical ablation condition.