Biophysical numerical model for pulsed field ablation

Area of Science:

• Biophysics
• Computational Modeling
• Cardiac Electrophysiology

Background:

• Pulsed-Field Ablation (PFA) is a promising non-thermal treatment for cardiac arrhythmias.
• Current predictive models for PFA lesion characteristics are limited in accuracy.
• Existing models often rely on macroscopic electric field criteria, neglecting cellular-level details.

Purpose of the Study:

• To develop a novel, biophysics-grounded, anisotropic model for cardiac PFA.
• To incorporate cellular geometry and orientation via transmembrane voltage for lesion prediction.
• To improve the accuracy of predicting PFA lesion size and shape, particularly width-to-depth ratios.

Main Methods:

• Derivation of an anisotropic PFA model through homogenization of a microscopic electroporation model.
• Utilizing local transmembrane voltage as a biologically meaningful ablation criterion.
• Development of a static model for predicting outcomes of multiple consecutive pulses.

Main Results:

• The model demonstrates that myocardial fiber anisotropy significantly impacts lesion morphology.
• The transmembrane voltage criterion improves prediction of lesion width-to-depth ratios compared to standard methods.
• Preliminary numerical results align with experimental epicardial ventricular observations.

Conclusions:

• The proposed mechanistic modeling framework links cell-scale and tissue-scale phenomena in PFA.
• Local tissue anisotropy is a critical factor influencing PFA lesion characteristics.
• This model offers a more accurate approach for predicting PFA outcomes in cardiac arrhythmia treatment.