Effect of catheter contact force on lesion volume in pulsed field ablation: A computational study

Cardiac arrhythmia is one of the most common disorders affecting millions of people globally. More recently, pulsed-field ablation (PFA) has received FDA approval and emerged to be a safe and effective treatment modality for treating different types of cardiac arrhythmia. Unlike other ablative techniques like radiofrequency ablation, PFA is non-thermal-energy approach based on irreversible electroporation phenomena for attaining highly selective cellular injury by administering microsecond-scale, high-voltage electrical pulses. Despite numerous feasibility studies highlighting PFA’s safety and efficacy, the exact mechanisms of action remain elusive. Substantial research efforts are essential to comprehensively understand PFA technology, leveraging its potential for sustainable health improvements. The objective of the present study is to quantify the relationship between the electrode–tissue proximity and the applied contact force on the shape and size of lesions induced during PFA. A coupled computational model was developed, incorporating electrical, thermal, mechanical, and fluid dynamics, simulating cardiac tissue as a hyper-elastic material. This study examined both the monopolar and bipolar electrode configurations. The outcomes were analyzed on the basis of ablation volume, as well as maximum temperature rise within the cardiac tissue and blood. It was found that the lesion dimensions induced during PFA are strongly correlated to the contact force at the electrode–tissue interface. Statistical correlations were developed to predict the lesion volume based on contact depth for monopolar and bipolar electrode configurations.