Pulsed Field Ablation for Atrial Fibrillation: Mechanism, Clinical Evidence, and Emerging Applications

Pulsed field ablation (PFA) is a nonthermal catheter ablation modality that uses high-voltage, ultra-short electrical pulses to induce irreversible electroporation of cardiomyocyte membranes. Unlike radiofrequency and cryoballoon energy, PFA exploits differential electroporation thresholds across tissue types, producing lesions that are largely confined to the myocardium while sparing the esophagus, phrenic nerve, and pulmonary veins. Multiple pivotal trials and large multinational registries have now established PFA as an effective and safe alternative to thermal ablation for both paroxysmal and persistent atrial fibrillation (AF), with freedom from atrial arrhythmia rates comparable to radiofrequency and cryoablation, and a distinct, energy-specific complication profile. Notable adverse events unique to PFA include transient coronary artery vasospasm, intravascular hemolysis with rare acute kidney injury, and microbubble-related embolic risk, while classic thermal complications, such as atrioesophageal fistula and pulmonary vein stenosis, have shown a markedly reduced observed incidence across large cohorts. This review summarizes the biophysical mechanism of PFA, synthesizes clinical trial and registry evidence for paroxysmal and persistent AF, details the energy-specific safety profile, and outlines emerging applications, including posterior wall isolation, ventricular arrhythmia ablation, and next-generation catheter design. As PFA adoption accelerates, understanding both its favorable safety profile and its unique failure modes is essential for electrophysiologists integrating this technology into practice.