Available at: https://digitalcommons.calpoly.edu/theses/3012
Date of Award
6-2025
Degree Name
MS in Biomedical Engineering
Department/Program
Biomedical Engineering
College
College of Engineering
Advisor
James Eason
Advisor Department
Biomedical Engineering
Advisor College
College of Engineering
Abstract
Cardiac arrhythmias are conditions where the heart’s normal sinus rhythm is interrupted by accelerated or premature rhythms. The most prevalent of these rhythms is atrial fibrillation (AF), where disorganized impulses cause the atria to quiver and pump blood inefficiently. As of 2025, AF affects over 10 million people. Aside from invasive surgical treatments, antiarrhythmic drugs, or one time cardioversions, atrial fibrillation is treated with catheter ablation. The longstanding ablation solutions for AF have been the cryoballoon or radiofrequency catheter ablation. However, limitations for these two ablation modalities are due to the nature of cell destruction; both thermal methods pose a risk of damaging tertiary structures to the heart. Pulsed field ablation (PFA) offers a non-thermal method for ablation, applying large amplitude, high frequency pulses to the tissue, causing cardiac cells to lyse. To interrogate the efficacy of specific pulse waveforms, modeling and simulation of lesion formation in cardiac tissue was performed using Comsol Multiphysics. Monophasic and biphasic pulses, some incorporating a biphasic delay parameter, were delivered to an area of tissue via a quadripolar catheter’s tip electrode towards an external return electrode. When analyzing monophasic pulses, charge delivered to the tissue was identified as the most reliable indicator of predicting lesion formation. When comparing monophasic and biphasic pulses of identical amplitude and pulse width, monophasic lesions yielded larger lesions. When a biphasic delay is incorporated between the two phases of a biphasic waveform, a longer delay results in a larger lesion formed.