Catheter ablation is one of the most effective rhythm-control strategies for atrial fibrillation (AF). Conventional catheter ablation is performed using thermo-energy sources via either radiofrequency that burns cardiac tissue through heat or cryoablation that freezes tissue under ultralow temperature. Although effective, thermo-energy is not selective of tissues other than myocardium and creates the risk of hemidiaphragmatic paralysis, atrioesophageal fistula, and pulmonary vein stenosis. Pulsed field ablation (PFA) is a novel nonthermal energy source that uses electroporation via microsecond-scale, high-voltage electrical field to create cell necrosis. PFA has the potential of being tissue selective and ultrafast in creating cell death during AF ablation. The results of previous preclinical and nonrandomized observational studies in humans have demonstrated PFA's effectiveness in achieving successful ablation in significantly shorter ablation times while being protective of surrounding tissues.¹

The ADVENT study was the first multicenter, randomized, noninferiority, single-blind trial that randomized patients with paroxysmal AF in a 1:1 fashion to undergo PFA (305 patients) or conventional radiofrequency or cryoablation (302 patients).² At 12-month follow-up, both the primary efficacy outcome (freedom from a composite of initial procedural failure, documented atrial tachyarrhythmia after a 3-month blanking period, antiarrhythmic drug use, cardioversion, or repeat ablation) and primary safety outcome (acute and chronic device-related and procedure-related serious adverse events) were noninferior to thermal ablation.² Although PFA did not demonstrate superior efficacy or eliminate procedure-related adverse events compared with current standards, the results of this study have proven that PFA is equally effective and safe to be considered a first-line ablation energy source. The potential for PFA remains largely uncovered as experience in pulse duration, voltage amplitude, dedicated ablation catheters, approaches to performing ablation, and many more is still being accumulated. As the field continues to understand this technology in more depth, clinicians can only be expected to be better at using PFA as an important tool to treat AF.

References

1. Verma A, Haines DE, Boersma LV, et al.; PULSED AF Investigators. Pulsed field ablation for the treatment of atrial fibrillation: PULSED AF pivotal trial. Circulation 2023;147:1422-32.
2. Reddy VY, Gerstenfeld EP, Natale A, et al.; ADVENT Investigators. Pulsed field or conventional thermal ablation for paroxysmal atrial fibrillation. N Engl J Med 2023;389:1660-71.