New ablation technology effectively treats atrial fibrillation
Presenter: Atul Verma, MD, McGill University Health Centre, Montreal, Canada
Pulsed field ablation treatment In paroxysmal and persistent atrial fibrillation patients: Acute and long-term outcomes from the Pulsed AF pivotal trial. Presentation number 409-08. Presented March 6, 2023.
A novel technology for atrial fibrillation ablation, called pulsed field ablation (PFA), can successfully eliminate both persistent and paroxysmal atrial fibrillation for 12 months in up to 80% of patients, according to results from the PULSED AF clinical trial.
Thermal modes of ablation, considered the standards of care for decades, are limited by the potential for collateral tissue damage. PFA creates lesions in cardiac tissue non-thermally through the mechanism of irreversible electroporation. This technique exposes tissue to high electric field gradients, which induces cell membrane hyper-permeabilization within milliseconds, leading to cell death.
“The efficacy of PFA is at least as good as thermal ablation, and the safety is very good,” said presenter Atul Verma, MD, of McGill University Health Centre, Quebec, Canada. “And the procedure is done in 30 to 40 minutes, substantially faster than 1.5 to 2 hours that standard ablation takes today.”
PULSED AF is the first large, prospective, multicenter global clinical trial to evaluate PFA. The nonrandomized trial was conducted at 41 sites in 9 countries. For the trial, physicians first treated one patient each with PFA to gain experience with the technique, for a total of 60 patients. After roll-in, 150 patients with paroxysmal atrial fibrillation and 150 patients with persistent atrial fibrillation who were refractory to anti-arrhythmic drugs were treated with PFA.
Baseline characteristics of study participants were typical of patients with atrial fibrillation, Verma said. Patients were in their mid-60s with left atrial diameters of about 40 mm.
Primary efficacy results show 66.2% of patients with paroxysmal atrial fibrillation and 55.1% of those with persistent atrial fibrillation experienced no atrial fibrillation episodes through 12 months, as measured by weekly and symptomatic self-reports, electrocardiograms, and 24-hour Holter monitoring. Freedom from atrial arrhythmia recurrence at 12 months was 69.5% in the paroxysmal atrial fibrillation group and 62.3% in the persistent atrial fibrillation group. Clinical success, defined as freedom from symptomatic atrial arrhythmia occurrence at 12 months, was 79.7% in the paroxysmal atrial fibrillation cohort and 80.8% in the persistent atrial fibrillation cohort.
Only 1 adverse event occurred in each cohort, for an adverse event rate of less than 1%. There was no evidence of pulmonary vein stenosis, coronary artery spasm, esophageal complications, or phrenic nerve injury. Both cohorts met predetermined safety goals.
In addition, all patients reported significant and meaningful improvements in quality of life.
In conclusion, Verma said that “both paroxysmal and persistent Afib cohorts met predetermined effectiveness performance goals. The primary safety endpoint rate of 0.7% was observed in both cohorts.”
“However, we are in the early days of PFA,” he added. “This is essentially a first-generation technology. We will still need to make adjustments, and comparative trials will be important.”
With the introduction of PFA, electrophysiology is poised to enter a new era. Verma said that PFA represents a paradigm shift and will take over much of the thermal ablation market. “There has been a huge amount of enthusiasm over this technology in the electrophysiology community. Many physicians feel that PFA will become the dominant way of doing ablation moving forward,” he said.
The results of the study were published simultaneously in Circulation: Arrhythmia and Electrophysiology.
References
Verma A, Boersma L, Haines DE, et al. First-in-human experience and acute procedural outcomes using a novel pulsed field ablation system: The PULSED AF pilot trial. Circ Arrhythm Electrophysiol 2022; 15(1):e010168. https://www.ahajournals.org/doi/10.1161/CIRCEP.121.010168
Verma, A. Pulsed field ablation treatment In paroxysmal and persistent atrial fibrillation
patients: Acute and long-term outcomes from the Pulsed AF pivotal trial. Presented at American College of Cardiology Annual Scientific Session & Expo Together With World Congress of Cardiology, March 6, 2023, New Orleans, LA. Presentation number 409-08.
Disclosures
Atul Verma. Consultant fees/honoraria: Adagio Medical, MedLumics.
Research/research grants: Bayer, Biosense Webster, Medtronic