We updated the design of this site on December 18, 2017. Learn more.
ClinicalTrials.gov Menu

A Clinical Study of the Arctic Front Cryoablation Balloon for the Treatment of Paroxysmal Atrial Fibrillation (Stop-AF)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT00523978
Recruitment Status : Completed
First Posted : September 3, 2007
Results First Posted : August 28, 2012
Last Update Posted : August 28, 2012
Information provided by (Responsible Party):
Medtronic Atrial Fibrillation Solutions

Brief Summary:
This study (STOP AF) is a prospective, randomized, controlled, multicenter, pivotal clinical investigation conducted at 26 investigational sites in the United States and Canada. Subjects with paroxysmal atrial fibrillation (PAF) referred for ablative intervention after efficacy failure of one or more Study Atrial Fibrillation (AF) Drugs (flecainide, propafenone or sotalol) were randomized 2:1 to cryoablation intervention (Experimental Subjects, ES) or to a Study AF Drug (Control Subjects, CS). Subjects were followed for 12 months with scheduled and symptom-driven assessments to detect recurrent atrial fibrillation by means of periodic electrocardiograms, weekly scheduled trans-telephonic monitoring, patient-initiated trans-telephonic monitoring, and 24-hour Holter monitoring at 6 and 12 months. The first 90 days after study therapy was initiated was considered a blanked period for all subjects.

Condition or disease Intervention/treatment Phase
Paroxysmal Atrial Fibrillation Device: Arctic Front® Cryoablation Catheter Drug: Flecainide or Sotalol or Propafenone Phase 3

Detailed Description:

STOP AF (PS-023) is a randomized, controlled study of subjects 18 to 75 years old who had been referred for ablative intervention after failing one or two (but not all three) anti-arrhythmic drugs used in the treatment of AF (flecainide, propafenone and sotalol). Study subjects were randomized into two arms: the cryoablation (treatment) arm and the membrane-active antiarrhythmic drug (control) arm. A 90- day blanked follow-up period, including reablation and medication adjustments was applied in both arms to optimize therapies. All subjects underwent follow-up assessments at 1, 3, 6, 9 and 12 months, weekly transtelephonic monitoring, 24-hour Holter monitoring and CT/MRI of the pulmonary veins(at 6 and 12 months) during the trial period. Control subjects who were confirmed to be chronic treatment failures were permitted to crossover to cryoablation in this trial.

Acute procedural success was defined for subjects that underwent cryoablation and demonstrated electrical isolation in ≥ 3 Pulmonary Veins (PVs) at the conclusion of the first protocol-defined cryoablation procedure using the Arctic Front® Cardiac CryoAblation Catheter System.

The primary effectiveness endpoint was defined as having acute procedural success and freedom from chronic treatment failure (CTF) for experimental subjects, and freedom from CTF for control subjects. Freedom from (CTF) was defined for both groups as the occurrence of detectable AF during a non-blanked follow-up period, or an AF Intervention, or the use of a non-study AF drug at any time.

The co-primary safety outcome measures were Cryoablation Procedure Events (CPEs) in cryoablated subjects and Major Atrial Fibrillation Events (MAFEs) in both groups. CPEs were device- or procedure-related serious adverse events.

Other safety assessments were made during the course of the STOP AF trial specific to pulmonary vein stenosis (PVS) and phrenic nerve injury.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 245 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: A Randomized, Controlled Clinical Trial of Catheter Cryoablation in the Treatment of Paroxysmal Atrial Fibrillation.
Study Start Date : October 2006
Primary Completion Date : August 2010
Study Completion Date : July 2011

Arm Intervention/treatment
Experimental: Experimental
Experimental subjects received cryoablation intended to isolate the pulmonary veins and ablate arrhythmia foci. If necessary, experimental subjects were allowed a previously failed Study Atrial Fibrillation Drug (AF Drug).
Device: Arctic Front® Cryoablation Catheter
Experimental Subjects received cryoablation intended to isolate the pulmonary veins and ablate arrhythmia foci with the cryoablation catheter system.
Other Names:
  • Arctic Front® Cardiac CryoAblation Catheter System
  • Artic Front®
Active Comparator: Control
Control Subjects were treated with an AF Drug (flecainide, propafenone, or sotalol) that they had not previously failed.
Drug: Flecainide or Sotalol or Propafenone
Flecainide 200 mg / day Propafenone 450 mg / day Propafenone-SR 650 mg / day Sotalol 240 mg / day
Other Names:
  • Tambocor
  • Sotalol
  • Propafenone

Primary Outcome Measures :
  1. Acute Procedural Success (APS) [ Time Frame: 371.4 Minutes (Average) ]
    Acute Procedural Success was defined as a demonstration of electrical isolation in ≥ 3 Pulmonary Veins (PVs) at the conclusion of the first protocol-defined cryoablation procedure. APS was decided at the end of the procedure the mean time was calculated for the time frame.

  2. Freedom From Chronic Treatment Failure (CTF) [ Time Frame: 12 month follow up period ]
    Subjects that did not have or were free of CTF. CTF was defined as the occurence of an Atrial Fibrillation (AF) intervention, use of non-study AF drug therapy, or the occurence of detectable AF which is is defined as an episode of AF, documented in a tracing, and lasting more than 30 seconds, occurring during a Non Blanked Follow-up Period.

  3. Treatment Success [ Time Frame: 12 months ]
    Treatment Success was defined as Acute Procedure Success (APS) and freedom from Chronic Treatment Failure (CTF) for Experimental Subjects, and freedom from CTF for Control Subjects. Under this pre-specified definition of Treatment Success, Experimental Subjects must have had APS and remained free of CTF during the 12-month follow-up duration, while Control Subjects must have remained free of CTF during the 12-month follow-up duration.

  4. Freedom From Major Atrial Fibrillation Events (MAFEs) [ Time Frame: 12 Months ]
    Subjects that did not have or were free of MAFEs. MAFEs were serious adverse events categorized as cardiovascular death, myocardial infarction, stroke, or hospitalization for AF recurrence/ablation, flutter ablation, embolic events, heart failure, hemorrhage or anti-arrhythmic drug treatment.

  5. Cryoablation Procedure Events (CPEs) [ Time Frame: To end of ablation procedure ]
    Subjects that had CPEs. CPEs were device- or procedure-related serious adverse events (SAE) categorized as access site complications, cardiac damage, pulmonary vein (PV) stenosis, embolic complications, arrhythmias, unresolved phrenic nerve palsy and death.

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   18 Years to 75 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Documented Paroxysmal Atrial Fibrillation (PAF): PAF diagnosis, 2 episodes of PAF within the last 2 months, at least 1 episode of PAF must be documented
  • Age 18-75
  • Documented Effectiveness Failure of one (1) AF drug
  • Willing to be randomized to either group and do full 12 month follow-up
  • Able to follow standardized AF drug protocol

Exclusion Criteria:

  • Any cardioversion within 3 months or more than 2 within 2 years
  • Amiodarone within 6 months
  • LA size > 5.0cm
  • Previous LA ablation/surgery, structural heart disease, heart failure class III or IV
  • Hypertrophic cardiomyopathy, Mitral prosthesis
  • Unstable angina, uncontrolled hyperthyroidism
  • Stroke or TIA within 6 months, MI within 2 months, cardiac surgery within 3 months
  • Thrombocytosis, thrombocytopenia
  • Any condition contraindicating chronic anticoagulation
  • EF <40%
  • Pregnancy
  • Life expectancy <1year

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00523978

  Hide Study Locations
United States, Alabama
University of Alabama
Birmingham, Alabama, United States, 35294-0007
United States, Arizona
Banner Good Samaritan Medical Center
Phoenix, Arizona, United States, 85006
United States, California
Cedar Sinai Medical Center
Los Angeles, California, United States, 90048
UC Davis Medical Center
Sacramento, California, United States, 98517
Stanford Hospital
Stanford, California, United States, 94305-5233
United States, Colorado
Colorado Cardiac Alliance -- Memorial Hospital
Colorado Springs, Colorado, United States, 80907
United States, Florida
Mayo Clinic- Jacksonville
Jacksonville, Florida, United States, 32224
BayHeart Group -- St-Joseph's Hospital
Tampa, Florida, United States, 33607
United States, Georgia
Emery Crawford Long Hospital
Atlanta, Georgia, United States, 30308
Piedmont Hospital
Atlanta, Georgia, United States, 30309
United States, Iowa
Iowa Heart Center
Des Moines, Iowa, United States, 50314
United States, Massachusetts
Massachusetts General Hospital
Boston, Massachusetts, United States, 02114
United States, Minnesota
Mayo Clinic
Rochester, Minnesota, United States, 55902
United States, New Mexico
New Mexico Heart Institute
Albuquerque, New Mexico, United States, 87102
United States, New York
Montefiore Medical Center
Bronx, New York, United States, 10467
United States, Ohio
Cleveland Clinic Foundation
Cleveland, Ohio, United States, 44195
United States, Pennsylvania
University of Pennsylvania Health
Philadelphia, Pennsylvania, United States, 19104-4283
United States, Texas
Baylor Heart and Vascular Hospital
Dallas, Texas, United States, 75226
United States, Virginia
Inova Research Center
Falls Church, Virginia, United States, 22042
Sentara CV Research Institute
Norfolk, Virginia, United States, 23507
Medical College of Virginia
Richmond, Virginia, United States, 23219
United States, Wisconsin
Cardiology Associates of Green Bay
Green Bay, Wisconsin, United States, 54301-3596
Arrhythmia Center of Southern WI
Milwaukee, Wisconsin, United States, 53215
Canada, Ontario
London Medical Health Sciences
London, Ontario, Canada, N6A5A5
Canada, Quebec
Montreal Heart Institute
Montreal, Quebec, Canada, H1T 1C8
Laval Hospital
Ste-Foy, Quebec, Canada, G1V 4G5
Sponsors and Collaborators
Medtronic Atrial Fibrillation Solutions
Principal Investigator: Douglas L. Packer, MD Mayo Clinic

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Medtronic Atrial Fibrillation Solutions
ClinicalTrials.gov Identifier: NCT00523978     History of Changes
Other Study ID Numbers: PS-023
First Posted: September 3, 2007    Key Record Dates
Results First Posted: August 28, 2012
Last Update Posted: August 28, 2012
Last Verified: July 2012

Keywords provided by Medtronic Atrial Fibrillation Solutions:
Atrial Fibrillation

Additional relevant MeSH terms:
Atrial Fibrillation
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes
Anti-Arrhythmia Agents
Voltage-Gated Sodium Channel Blockers
Sodium Channel Blockers
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Adrenergic beta-Antagonists
Adrenergic Antagonists
Adrenergic Agents
Neurotransmitter Agents
Physiological Effects of Drugs
Autonomic Agents
Peripheral Nervous System Agents