PULSED-AF: Pulsed-field ablation safe and effective for treating atrial fibrillation

The 300-patient trial, the findings of which are published in Circulation, was designed for the US FDA (Food and Drug Administration) consumption as it considered approval of the tested device, Medtronic's PulseSelect PFA system.

The trial showed a low rate of primary safety adverse events (0.7%) and effectiveness consistent with established ablation technologies using novel irreversible electroporation energy for treating atrial fibrillation patients.

Radiofrequency catheter ablation in some forms of atrial fibrillation has been a standout success but not an unqualified success —it has safety issues, doesn't always work and has other limitations. Thus, the continued search for alternative arrhythmia ablation technologies has notably produced cryo-balloons and, lately, an exotic assortment of pulsed-field ablation catheters.

Pulse field ablation utilizes electrical pulses to cause nonthermal irreversible electroporation and produce cardiac cell death. Pulsed-field ablation may have effects comparable to traditional catheter ablation while preventing thermally mediated complications.

Atul Verma, McGill University Health Centre, Montreal, QC, Canada, and colleagues conducted the PULSED AF pivotal study, a prospective, global, multicenter, nonrandomized, paired single-arm study. It included patients with persistent (n=150) or paroxysmal (n=150) AF despite class I or III antiarrhythmic drugs at 41 centres in Western Europe, North America, Australia, and Japan treated with PFA. Using weekly and symptomatic trans telephonic monitoring consisting of 6- and 12-month 24-hour Holter monitoring and 3-, 6-, and 12-month ECGs, all patients were monitored for one year.

The primary safety endpoint was freedom from a composite of serious adverse events related to the procedure or device. Freedom from a composite of arrhythmia recurrence, acute procedural failure, or antiarrhythmic escalation through 12 months was determined, excluding a 3-month blanking period allowing recovery (primary effectiveness endpoint). Primary endpoints were evaluated using Kaplan-Meier methods.

The authors reported the following findings:

• Pulsed-field ablation was effective at one year in 66.2% of patients with paroxysmal AF and 55.1% with persistent AF.
• The primary safety endpoint occurred in 1 patient (0.7%) in the paroxysmal and persistent AF cohorts.

To conclude, PULSED AF showed a low rate of primary safety adverse events and provided effectiveness consistent with established ablation technologies using novel irreversible electroporation energy to treat AF patients.

Reference:

The study, "Pulsed Field Ablation for the Treatment of Atrial Fibrillation: PULSED AF Pivotal Trial" was published in Circulation. DOI: https://doi.org/10.1161/CIRCULATIONAHA.123.063988