A new analysis of data from a larger clinical trial suggests that pulsed field ablation (PFA) may offer a safe and efficient alternative to traditional radiofrequency ablation (RFA) for treating persistent atrial fibrillation (AFib), specifically during cavotricuspid isthmus (CTI) ablation to address typical atrial flutter. The findings, published in in the Journal of the American College of Cardiology (JACC), build upon the results of the ADVANTAGE AF study.
Atrial fibrillation is an irregular and often rapid heart rhythm that can lead to stroke, heart failure, and other complications. CTI ablation is a common procedure used to correct atrial flutter, a type of irregular heartbeat often occurring alongside AFib. Traditionally, this procedure has been performed using RFA, which uses heat to create scar tissue and block abnormal electrical signals in the heart. PFA, a newer technology, utilizes electrical pulses instead of heat, potentially minimizing damage to surrounding tissues.
The subanalysis compared outcomes in 191 patients undergoing CTI ablation: 50 treated with RFA and 141 treated with bipolar linear PFA. Researchers, led by Dr. Edward P. Gerstenfeld and colleagues, found that acute CTI conduction block – meaning the procedure successfully stopped abnormal electrical signals – was achieved in a similar percentage of patients in both groups (100% with RFA and 98.6% with PFA). Importantly, safety event rates were also comparable (2% for RFA versus 2.1% for PFA).
However, a key difference emerged in procedure duration. The median time to complete CTI ablation was significantly shorter with PFA (5 minutes) compared to RFA (14 minutes). This reduced procedure time could potentially translate to benefits for both patients and healthcare systems.
The study also addressed a potential concern regarding coronary artery spasm, a narrowing of the arteries supplying the heart, which can occur during ablation procedures. Researchers implemented a standardized protocol involving pretreatment with nitroglycerin for patients undergoing PFA. Notably, no clinical manifestations of coronary artery spasm were observed in the PFA group following this protocol.
“This subanalysis of ADVANTAGE AF extends the primary results by allowing comparison of bipolar linear PFA and RF ablation for CTI, integrating preclinical lesion modeling with clinical dosing, and establishing a standardized reliable coronary safety protocol,” explained Dr. Gerstenfeld and colleagues in their publication. They suggest that the findings “may extend electroporation from the pulmonary veins to linear substrates, and allow a single nonthermal ablation platform for treatment of [AFib and atrial flutter].”
In an accompanying editorial, Dr. Ayman A. Hussein and Dr. Oussama M. Wazni highlighted the growing adoption of PFA, noting that its uptake has “outpaced scientific evidence because of enhanced safety and efficiency vs. Thermal ablations.” They emphasized that PFA “marks the beginning of a new era for cardiac electrophysiology.”
The editorial also pointed to areas for future research. Dr. Hussein and Dr. Wazni suggest a need for studies evaluating the long-term effects of PFA, as well as efforts to improve the prediction of PFA lesion size and explore opportunities to integrate the technology with advanced imaging and mapping techniques. These advancements could further refine the precision and effectiveness of PFA procedures.
The ADVANTAGE AF trial, which provided the data for this subanalysis, involved 355 patients across 43 medical centers. All patients received pulmonary vein isolation (PVI) plus posterior wall ablation (PWA) using the FARAWAVE pentaspline PFA catheter system, developed by Boston Scientific. Previous results from the trial demonstrated a primary safety endpoint of 2.3% and a primary effectiveness rate of 63.5% at one year, exceeding pre-defined performance goals.
While the subanalysis is not a randomized comparison, the findings add to the growing body of evidence supporting the potential benefits of PFA as a treatment option for atrial fibrillation and related arrhythmias. The shorter procedure times and comparable safety profile observed in this study suggest that PFA could become an increasingly important tool for electrophysiologists in the years to come. Further research will be crucial to fully understand the long-term implications of this innovative technology.
