Controlling pulsed field ablation efficacy during ablation procedures

Pulsed field ablation (PFA) has rapidly emerged as a promising ablation modality for the treatment of cardiac arrhythmias because of its myocardial tissue preferential ablation and favourable safety profile. However, procedural control of lesion formation and reliable assessment of lesion durability remain important challenges. This review summarizes the main determinants of PFA efficacy and current approaches for intraprocedural lesion assessment. Experimental and clinical studies indicate that PFA lesion formation results from the interaction between delivered electrical energy, catheter design, tissue coupling, and application strategy. Lesion size and geometry are primarily determined by electric field distribution and cumulative electroporation exposure, while excessive energy delivery may induce unwanted thermal or electrochemical effects. Procedural efficacy also depends on stable catheter positioning, adequate tissue proximity, and sufficient lesion overlap. Unlike thermal ablation technologies, conventional procedural markers such as electrogram attenuation, impedance changes, and pacing threshold variation correlate poorly with durable irreversible electroporation. Multiparametric lesion estimation models integrating electrical, mechanical, and positional data have shown encouraging preclinical results, although clinical validation remains limited. Emerging strategies combining electroanatomical mapping, imaging, and automated electrogram analysis may improve real-time evaluation of lesion continuity and durability. Current PFA workflows rely mainly on standardized energy delivery protocols, optimized catheter positioning, and lesion overlap rather than real-time titration of energy. Although robust intraprocedural markers of irreversible electroporation are still lacking, ongoing advances in catheter technology, imaging, and lesion assessment tools are expected to improve procedural reproducibility and long-term lesion durability. Further studies are needed to establish validated endpoints for durable PFA lesion formation.