Pulsed field ablation (PFA) is noninferior to cryoablation for the incidence of a first recurrence of atrial tachyarrhythmia in patients with paroxysmal atrial fibrillation (AFib), according to results from the SINGLE SHOT CHAMPION trial published in the New England Journal of Medicine.

Tobias Reichlin, MD, et al., randomly assigned 210 patients with symptomatic paroxysmal AFib (mean age of 64 years, 28% women) to undergo PFA (n=105) or cryoablation (n=105) from September 2022 to November 2023 at two tertiary care centers in Switzerland. All patients received an implantable cardiac monitor to assess continuous rhythm and detect atrial tachyarrhythmias.

Results showed that a recurrence of atrial tachyarrhythmia between day 91 and day 365 after ablation (the primary endpoint) occurred in 39 patients in the PFA group and in 53 patients in the cryoablation group (Kaplan-Meier cumulative incidence, 37.1% and 50.7%, respectively; p<0.001 for noninferiority, p=0.046 for superiority).

The primary safety endpoint – a composite of procedure-related complications – occurred in one patient in the PFA group and 2 patients in the cryoablation group. In other findings. researchers noted that quality of life and use of antiarrhythmic drugs were similar between the two groups, while repeat ablations were numerically more frequent in the PFA group.

According to Reichlin and colleagues, several factors could explain their findings, including that PFA "may create a broader ablation zone inside and around the pulmonary veins owing to the device design" and that it may also "yield more durable lesions, thereby reducing pulmonary-vein reconnections."

They also add that a key feature of their trial involved continuous rhythm monitoring, "which eliminated sampling errors and enabled a more comprehensive assessment of ablation efficacy." Looking ahead, they say larger outcomes trials are needed to answer the question of whether PFA is superior to cryoablation

In an accompanying editorial comment, Jason G. Andrade, MD, congratulates the trial authors for "providing new insights into the comprehensive effect of invasive interventions for [AFib]," including reaffirmation that arrhythmia monitoring plays a fundamental role in influencing outcome reporting and showing "that the concept of survival free from atrial tachyarrhythmia ... is of limited use." He adds that "a true understanding of the value of therapeutic interventions must move beyond binary outcomes and necessitates the consideration of comprehensive analysis of patient-centric outcomes, as well as an assessment of the economic effect of the intervention."