The OneFreeze Study (OneFreeze)

A Prospective Multi-center Randomized Controlled Trial to Assess the Safety and Efficacy of One vs. Two Cryoablations Per Pulmonary Vein for the Treatment of Atrial Fibrillation

The One Freeze study is a prospective multi-center randomized controlled trial to assess the safety and efficacy of one vs. two cryoablations per pulmonary vein for the treatment of atrial fibrillation.

Study Overview

• Status: Completed
• Conditions: Paroxysmal Atrial Fibrillation
• Intervention / Treatment: Procedure: Atrial fibrillation catheter ablation using the Medtronic Arctic Front Ablation System

Detailed Description

The One Freeze Trial is an investigator-initiated trial that has been developed by the Principals at the University of California, San Francisco (UCSF) and with full participation of the Steering Committee. One Freezel is a prospective multicenter randomized controlled trial with a goal to enroll and randomize a minimum of 90 study participants. Participants will be randomized in a 1:1 ratio to either PVI with a single freeze per pulmonary vein (1F Group) or to PVI with at least two freezes per pulmonary vein (2F Group). The One Freeze study's primary aim is to determine if one 3-minute cryoablation per pulmonary vein results in a lower composite adverse event score as compared to the traditional method of using two 3-minute cryoablations per pulmonary vein.

• Study Type: Interventional
• Enrollment (Actual): 90
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Québec, Canada
    • Montreal Heart Institute
• United States
  • California
    • San Francisco, California, United States, 94122
      • University of California, San Francisco
  • Washington
    • Seattle, Washington, United States, 98101
      • Virginia Mason Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Paroxysmal atrial fibrillation
• Age ≥ 18 years
• Life expectancy ≥ 1 year
• Willing and able to return to and comply with scheduled follow-up visits
• Willing and able to provide written informed consent

Exclusion Criteria:

• History of > 5 electric cardioversions
• History of previous pulmonary vein isolation ablation for atrial fibrillation
• History of MAZE procedure
• Left ventricular EF ≤ 35% within the past 12 months
• Mechanical mitral valve
• Single PV > 30 mm in diameter, unless deemed appropriate by the site PI
• Stroke/TIA within the past 6 months
• Creatinine > 2.0 mg/dL within the past 6 months
• Pregnancy or desire to get pregnant within the next 12 months
• Current enrollment in an investigation or study of a cardiovascular device or investigational drug that would interfere with this study
• Mental impairment or other conditions, which may not allow the participant to understand the nature, significance and scope of the study
• Any other condition or circumstance that in the judgment of the Clinical Site Investigator that makes the participant unsuitable for the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: two 3-minute cryoablations; two 3-minute cryoablations per pulmonary vein during an atrial fibrillation ablation procedure	Procedure: Atrial fibrillation catheter ablation using the Medtronic Arctic Front Ablation System; Other Names: Pulmonary vein isolation; Cryoballoon catheter ablation
Active Comparator: One 3-minute cryoablation; One 3-minute cryoablation per pulmonary vein during an atrial fibrillation ablation procedure	Procedure: Atrial fibrillation catheter ablation using the Medtronic Arctic Front Ablation System; Other Names: Pulmonary vein isolation; Cryoballoon catheter ablation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Composite Score of Adverse Events	Composite score of adverse events (Range 0-20 points) will be calculated after the patient has completed follow-up. Higher scores indicate greater severity. Luminal Esophageal Temperature (LET) (0-2 points): 1-point if ≤20 degrees C, 2-points if ≤15 degrees C Phrenic nerve injury (0-3 points): 1-point if ≥30% decrease in compound muscle action potential (CMAP) or loss of phrenic nerve capture resulting in cessation of freeze (without movement of pacing catheter), 2-points if Phrenic nerve palsy lasting> 1 minute resolving on table, 3-points if Phrenic nerve palsy not resolving on the table Pulmonary (0-4 points): 1-point if persistent dry cough > 1 week post ablation, 4-points if Hemoptysis Gastrointestinal (GI) (0-6 points): 1-point if Gastroparesis symptoms, 3-points if Esophageal ulceration, 6-points if left atrial-esophageal fistula Pulmonary vein (PV) stenosis (0-5 points): 1-point if ≥50% luminal area, 4-points if ≥90% luminal area, 5-points if total occlusion	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Participants free from symptomatic atrial fibrillation (AF)	Participants experiencing no episodes of AF greater than 30 seconds, excluding episodes documented in the blanking period (6 weeks post-ablation for paroxysmal AF patients).	6 months and 12 months
Atrial Fibrillation (AF) burden	AF burden is defined as the overall percentage of AF during the 14-day observed period on Holter monitoring at 6 months and 12 months.	6 months, 12 months
Procedure Time	The duration of the Pulmonary Vein Isolation procedure from first leg puncture to removal of ablation catheter	4 - 8 hours
Left Atrial Access time	Time it takes to gain transseptal access during the catheter ablation procedure	4 - 8 hours
Fluoroscopy Time	The amount of time in minutes (and milligray (mGy)/millisievert (mSv) dosage) of fluoroscopy used during the procedure	4 - 8 hours
Number of cryoablations needed to isolate each vein	Number of cryoablations needed to isolate each vein	4 - 8 hours
Acute success of the Pulmonary Vein Isolation (PVI)	percentage of pulmonary veins isolated during the catheter ablation procedure	4 - 8 hours
Individual Adverse Events	Number and severity of adverse events following the PVI procedure during the 12-month follow-up window	within 12 months after the Pulmonary Vein Isolation (PVI)
Number of re-isolations required	Number of pulmonary veins requiring touch up for re-isolation after initial isolation was achieved.	4 - 8 hours

Collaborators and Investigators

• Sponsor: University of California, San Francisco
• Collaborators: Medtronic
• Investigators: Principal Investigator: Byron K Lee, MD, University of California, San Francisco

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2014
• Primary Completion (Actual): October 1, 2019
• Study Completion (Actual): October 1, 2019

Study Registration Dates

• First Submitted: August 8, 2014
• First Submitted That Met QC Criteria: August 14, 2014
• First Posted (Estimated): August 15, 2014

Study Record Updates

• Last Update Posted (Actual): September 21, 2023
• Last Update Submitted That Met QC Criteria: September 18, 2023
• Last Verified: September 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Heart Diseases; Cardiovascular Diseases; Arrhythmias, Cardiac; Atrial Fibrillation
• Other Study ID Numbers: UC-OF01

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No