Numerical Analysis on the Effects of Saline Injection and Deformation for Radiofrequency Catheter Ablation

Radiofrequency catheter ablation is an interventional procedure used to treat arrhythmia. An electrode catheter that could inject saline has been developed to prevent steam pop on heart tissue during radiofrequency catheter ablation. Thus, we investigated to numerical model on the effect of saline injection and heart tissue's deformation. In this study, the hyperelastic model was implemented to analyze heart tissue deformation due to the catheter's contact force. Besides, the advection-diffusion equation was used to analyze the mixture between saline and blood. We developed the multiphysics model that predicts thermal lesions based on the deformation of the heart and mixing between saline and blood flow. The thermal lesion and the maximum temperature in the numerical model that considered mixing saline and blood were smaller than that of other numerical models that did not consider mixing. Therefore, we observed that the saline injection was affected by thermal lesion due to higher electrical conductivity than blood flow and injection at a lower temperature than the human body. The numerical model was researched that considering the deformation of the heart tissue and saline injection in radiofrequency catheter ablation affects the heart tissue's thermal lesion and maximum temperature.