Cryoballoon vs Radiofrequency Ablation for Persistent AF: Safety and Efficacy

The efficacy and safety of catheter ablation for persistent atrial fibrillation (AF) with cryoballoon ablation vs radiofrequency ablation will be compared in the prospective, multicenter, randomized, controlled Cryoballoon Ablation vs Radiofrequency Ablation in Patients with Persistent Atrial Fibrillation (CRRF-PeAF) study. Details of the study were published in the International Journal of Cardiology: Heart & Vasculature.

In the CRRF-PeAF study, the primary hypothesis is that cryoballoon ablation is not inferior to radiofrequency ablation in terms of clinical efficacy in patients with persistent AF. The study is intended to compare cryoballoon ablation with radiofrequency ablation at 1 year in patients with persistent AF between April 8, 2021, and March 31, 2029. The study enrollment period is from April 8, 2021, to March 31, 2025.

The target sample size for the study cohort is 500 patients with persistent AF (250 in the cryoballoon ablation group and 250 in the radiofrequency ablation group). The patients will be randomly assigned to either the cryoballoon or the radiofrequency ablation group in a 1:1 ratio, which will be based on a scheme that includes age (<75 vs ≥75 years), sex, and left atrial dimension (<45 mm vs ≥45 mm). All patients will be from 12 study hospitals in Japan. If the number of enrolled patients is not attained during the allotted time frame, the enrollment and study period will be extended. In the event that the number of enrolled patients is achieved earlier, then the enrollment and study period will be shortened.

Personal study visits will take place at 1 month and then every 1 to 3 months following the index procedure. At each study visit, patients will receive a medical history, physical examination, and 12-lead electrocardiogram. Additionally, 24-hour Holter recordings will be carried out at 3, 12, 24, and 36 months following the index procedure. All participants also will receive echocardiography and quality of life (QOL) questionnaires at baseline and 12, 24, and 36 months after the index procedure.

The primary study endpoint will be freedom from any atrial tachyarrhythmias lasting for 30 seconds or longer that occurred outside the blanking period of 90 days at 1 year following the index procedure. Any repeat ablation procedures performed for any atrial tachyarrhythmias during the blanking period will be deemed a recurrence.

Key secondary endpoints include the following:

• freedom from any atrial tachyarrhythmias at 3 years following the index procedure
• change/percent change in left ventricular ejection fraction at 1 year and at 3 years
• change/percent change in creatinine clearance and brain natriuretic peptide level at 1 year and at 3 years
• cardiovascular (CV) events at 1 year and at 3 years
• all-cause mortality and CV mortality at 1 year and at 3 years
• change/percent change in QOL at 1 year and at 3 years
• success rate of the pulmonary vein isolation, total procedure time, left atrial dwell time, total fluoroscopy time, radiation exposure, and quantity of contrast media
• efficacy of an adjunctive ablation lesion set
• rates of complications

Study inclusion criteria are as follows:

• diagnosed with persistent AF with a continuous AF episode of longer than 7 days but 1 year or less
• aged 20 to 85 years
• planned catheter ablation with the use of cryoballoon or radiofrequency ablation
• ability to comply with the protocol and provide written informed consent.

In order to exclude the presence of thrombi in the left atrial appendage and left atrium prior to the catheter ablation, all participants will receive a transesophageal echocardiography and/or contrast-enhanced computed tomography. All antiarrhythmic drugs other than amiodarone will be discontinued for 5 half-lives or longer prior to the catheter ablation. Additionally, oral anticoagulants will be prescribed for a minimum of 4 weeks prior to the catheter ablation.

All adverse events (defined as any adverse medical occurrence to patients during the study period, regardless of whether or not it is related to the ablation procedure) will be obtained during the study.

“The CRRF-PeAF study will be the first to compare the efficacy and safety of [catheter ablation] of persistent AF between [cryoballoon] and [radiofrequency] ablation in a prospective, multicenter, randomized, controlled fashion,” the study authors wrote.

Disclosure: Some of the study authors have declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures. 

Reference

Miyamoto K, Kanaoka K, Yoh M, et al. Cryoballoon Ablation versus Radiofrequency Ablation in Patients with Persistent Atrial Fibrillation (CRRF-PeAF): protocol for a prospective, multicenter, randomized, controlled study. Int J Cardiol Heart Vasc. Published online June 5, 2022. doi: 10.1016/j.ijcha.2022.101074.