Impedance based prediction of pulsed field ablation lesion depth without contact force

The lesion depth prediction index has been demonstrated to optimize ablation strategies. However, contact force-based prediction of lesion depth is difficult to integrate into multi-electrode catheters with complex shapes. This study developed and validated a contact force-independent pulsed-field ablation (PFA) index, the depth prediction index (DPI). Computer modeling identified parameters potentially affecting lesion formation. For in vivo experiments, six swine were assessed 2 h post-ablation to evaluate the difference between DPI and actual lesion depth, and two swine were assessed one month post-ablation to evaluate the difference. DPI predicted 131 of 156 lesions (84.0%) within 1.0 mm of measured depth, with a Pearson correlation coefficient of 0.74, a root mean square error (RMSE) of 0.68 mm, and a mean absolute error (MAE) of 0.56 mm. The DPI–depth association remained significant after adjustment for application number and within-animal clustering (adjusted coefficient, 0.628 mm; 95% CI, 0.505–0.751; P < 0.001). The DPI effectively predicts lesion depth without requiring contact force. This provides proof of feasibility for impedance-based prediction of PFA lesion depth and opens up a new direction for future lesion depth prediction in multi electrode PFA catheters.