Modeling Impact of Simulated Myocardial Perfusion on Cardiac Ablation for Arrhythmia

Bioheat transfer is the study of heat transfer applied in anatomy and physiology, which is relevant to maintaining homeostatic conditions from metabolic activity, thermal exposures, and various treatments and diagnostic methods. Blood flow significantly impacts heat transfer throughout the body, facilitating the diffusion of heat. Models have been developed to quantify bioheat transfer and the effect of blood flow through tissue for many biological functions and medical procedures, one of which is radiofrequency ablation for cardiac arrhythmia. Significant improvements to models and assumptions are still required as success rates for this procedure remain low for various arrhythmia types. The research objectives of this work are to model and determine the impact of perfusion through a tissue-mimicking phantom both experimentally and numerically. A parametric study of flow rate through embedded piping was performed to determine how that perfused flow impacts the transient thermal profile at different depths in the phantom. This study used an experimental setup using a tissue-mimicking phantom with embedded piping for perfusion with a copper heating element to perform thermal ablation trails. A computational fluid dynamics simulation in ANSYS was used to validate experimental results. Analytical methods validated numerical results, and a mesh sensitivity analysis was conducted to maximize computational efficiency. Experimental results were compared with the computational results. Results from this study confirm that perfusion impacts the transient thermal profile from advection through the phantom, reducing the measured temperature below the embedded pipe by more than 2 °C. As the rate of perfusion increased, the final temperature decreased in both experimental and numerical trials. Further research is needed to expand this foundation into clinically relevant experimentation with more complicated vasculature and heating methods using radiofrequency ablation.