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Boston Scientific's Cryoballoon in the Treatment of Symptomatic Drug Refractory Paroxysmal Atrial Fibrillation (FROZEN-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. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT04133168
Recruitment Status : Recruiting
First Posted : October 21, 2019
Last Update Posted : September 2, 2020
Information provided by (Responsible Party):
Boston Scientific Corporation

Brief Summary:
To establish the safety and effectiveness of the Boston Scientific Cardiac Cryoablation System for treatment of symptomatic, drug refractory, recurrent, paroxysmal atrial fibrillation (AF).

Condition or disease Intervention/treatment Phase
Paroxysmal Atrial Fibrillation Device: POLARx™ Cardiac Cryoablation System Not Applicable

Detailed Description:
Multi-center, open label, prospective, single arm study to document the safety and performance of Boston Scientific's Cryoablation System. The Cryoablation System is intended for cryoablation and electrical mapping of the pulmonary veins for pulmonary vein isolation (PVI) in the ablation treatment of patients with paroxysmal atrial fibrillation (PAF). All subjects fitting the enrollment criteria, signing the consent and undergoing the index procedure with the study devices will be followed up for twelve (12) months after the index procedure.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 405 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Intervention Model Description: open label, prospective, single arm study
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Safety and Effectiveness IDE Trial for Boston Scientific's Cryoballoon in the Treatment of Symptomatic Drug Refractory Paroxysmal Atrial Fibrillation
Actual Study Start Date : June 24, 2020
Estimated Primary Completion Date : April 30, 2022
Estimated Study Completion Date : April 30, 2022

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: Cryoablation
Subjects undergoing cardiac ablation procedure with the POLARx™ Cardiac Cryoablation System
Device: POLARx™ Cardiac Cryoablation System

The POLARx Cardiac Cryoablation System is intended for ablation and electrical mapping of the pulmonary veins for pulmonary vein isolation (PVI) in the ablation treatment of patients with paroxysmal atrial fibrillation (PAF).The system consists of the following devices and components:

  • POLARx™ Cryoablation Catheter
  • POLARMAP™ Catheter
  • SMARTFREEZE™ Console
  • Diaphragm Movement Sensor (DMS)
  • Related Accessories

Primary Outcome Measures :
  1. Rate of Primary Safety Events at 12 Months post-procedure (acute and chronic events) [ Time Frame: 12 Months ]
    composite of procedure-related and device-related adverse events. 7 days (Death, Myocardial infarction, Transient ischemic attack, Stroke/ Cerebrovascular accident, Vascular access complications, Mitral or tricuspid valvular damage, Thromboembolism/ Air embolism leading to a life-threatening event such as a ventricular arrhythmia, stroke, pulmonary embolism, or myocardial infarction and, thromboembolic events that result in permanent injury, require intervention for treatment or prolongs or require hospitalization for more than 48 hours, Gastroparesis/injury to vagus nerve, Pneumothorax, Pulmonary edema/heart failure AV block); 30 days (Cardiac tamponade/perforation); 12 months: (Atrial esophageal fistula, Severe Pulmonary vein stenosis, Persistent phrenic nerve palsy .

  2. Freedom from Treatment Failure at 12 Months post-procedure. [ Time Frame: 12 Months ]
    freedom from the composite of: 1)Failure to achieve acute procedural success in the index procedure or repeat procedure during the blanking period; 2 Use of amiodarone post index procedure; 3 Surgical treatment for AF/AFL/AT post index procedure; 4) Use of a non-study ablation catheter for AF targets in the index procedure or repeat procedure during the blanking period; 5) More than one repeat procedure with the POLARx catheter during the blanking period (90 days post index procedure); 6) Documented atrial fibrillation, or new onset of atrial flutter or atrial tachycardia event between days 91 and 365 days post index procedure; 7) Any of the following interventions for atrial fibrillation, or new onset of atrial flutter or atrial tachycardia between days 91 post index procedure and 365 days:Repeat procedure - Electrical and/or pharmacological cardioversion for AF/AFL/AT - Prescribed any antiarrhythmic drug (AAD)*

Secondary Outcome Measures :
  1. Rate of Acute Procedural Success defined as the achievement of electrical isolation of all PVs by using the Cardiac Cryoablation system [ Time Frame: 1 day ]
    the achievement of electrical isolation of all PVs by using the POLARx Cardiac Cryoablation system only. Electrical isolation of a PV is demonstrated by entrance and exit block.

  2. Rate of reportable Adverse Events at 12 months [ Time Frame: 12 months ]
    • All Serious Adverse Events
    • All Study Procedure-Related Adverse Events
    • All Study Device-Related Adverse Events
    • All Study Device Deficiencies
    • Unanticipated Adverse Device Effects/Unanticipated Serious Adverse Device Effects previously not defined in Investigator's Brochure or DFU

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.

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

Inclusion Criteria:

  • History of recurrent symptomatic Paroxysmal Atrial Fibrillation, defined as AF that terminates spontaneously or with intervention (either procedure or drug therapy) within seven days of onset. Minimum documentation includes at least two separate AF episodes within 6 months prior to enrollment documented with physician's note. At least one of these episodes must be documented with Holter monitor, rhythm strip, TTM or 12-leads ECG;
  • No amiodarone use within 90 days prior to enrollment;
  • Subjects who are indicated for an ablation procedure for paroxysmal atrial fibrillation (PAF) according to 2017 HRS expert consensus statement on catheter and surgical ablation of atrial fibrillation;
  • Subjects refractory or intolerant to at least one class I or III antiarrhythmic medication;
  • Subjects who are willing and capable of providing informed consent;
  • Subjects who are willing and capable of participating in all testing associated with this clinical investigation at an approved clinical investigational center;
  • Subjects whose age is 18 years or above, or who are of legal age to give informed consent specific to state and national law.

Exclusion Criteria:

  • Any known contraindication to an AF ablation or anticoagulation;
  • Continuous AF lasting longer than seven (7) days from onset;
  • History of previous left atrial ablation or surgical treatment for AF/ AFL/ AT;
  • Atrial fibrillation secondary to electrolyte imbalance, thyroid disease, or any other reversible or non-cardiac cause;
  • Body Mass index (BMI) ≥ 40;
  • Subject age at enrollment >75 years;
  • Structural heart disease or implanted devices as described below:

    1. Left ventricular ejection fraction (LVEF) < 40% based on the most recent transthoracic echocardiogram (TTE) (≤180 days prior to enrollment);
    2. Left atrial diameter > 55 mm OR left atrial volume > 50 ml/m2 ml indexed based on the most recent TTE (≤ 180 days prior to enrollment);
    3. An implanted pacemaker, ICD, CRT device or an arrhythmia loop recorder;
    4. Previous cardiac surgery: i.e. ventriculotomy or atriotomy (excluding atriotomy for CABG);
    5. Previous cardiac valvular surgical or percutaneous procedure, or prosthetic valve, including mitral valve clips;
    6. Interatrial baffle, closure device, patch, or patent foramen ovale (PFO) occlude;
    7. Presence of a left atrial appendage occlusion device;
    8. Presence of any pulmonary vein stents;
    9. Coronary artery bypass graft (CABG), PTCA/ PCI/ coronary stent procedures within 90 days prior to enrollment;
    10. Unstable angina or ongoing myocardial ischemia;
    11. myocardial infarction within 90 days prior to enrollment;
    12. Moderate or severe mitral insufficiency assessed on the most recent TTE (≤180 days prior to enrollment, e.g. pulmonary artery pressure >30 mmHg);
    13. Evidence of left atrial thrombus;
  • Any previous history of cryoglobulinemia;
  • Stage 3B or higher renal disease (estimated glomerular filtration rate, eGFR <45 mL/min);
  • History of blood clotting or bleeding disease;
  • Any prior history of documented cerebral infarct, TIA or systemic embolism [excluding a post-operative deep vein thrombosis (DVT)] ≤180 days prior to enrollment;
  • Active systemic infection;
  • Pregnant, lactating (current or anticipated during study follow up), or women of childbearing potential who are, or plan to become, pregnant during the time of the study (method of assessment upon physician's discretion);
  • Subjects who are currently enrolled in another investigational study or registry that would directly interfere with the current study, except when the subject is participating in a mandatory governmental registry, or a purely observational registry with no associated treatments; each instance must be brought to the attention of the sponsor to determine eligibility;
  • Subjects who in the judgment of the investigator have a life expectancy of less than two years.

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 identifier (NCT number): NCT04133168

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Contact: Susan Hampson . +1 (508) 728-5165
Contact: Giovanni Raciti +39 348 2502687

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United States, Arkansas
Nair Research, LLC. Recruiting
Jonesboro, Arkansas, United States, 72401
Contact: Kayla Rubino, RN   
Principal Investigator: Devi Nair, MD         
United States, California
Mercy General Hospital Recruiting
Sacramento, California, United States, 95819
Contact: Christie Hogan   
Principal Investigator: Aryana Arash, MD         
United States, Florida
Tallahassee Memorial Hospital Recruiting
Tallahassee, Florida, United States, 32308
Contact: Rebecca Plasay, RN   
Principal Investigator: Venkata Bavikati, MD         
AdventHealth Tampa Recruiting
Tampa, Florida, United States, 33613
Contact: Cynthia Paysor, RN   
Principal Investigator: Kenneth Yamamura, MD         
United States, New Jersey
Valley Hospital Recruiting
Ridgewood, New Jersey, United States, 07450
Contact: Kimberly Michel, RN   
Principal Investigator: Suneet Mittal, MD         
United States, New York
Mount Sinai Medical Center Recruiting
New York, New York, United States, 10029
Contact: Jeff Lam   
Principal Investigator: Marc Miller, MD         
Northwell Health Recruiting
Staten Island, New York, United States, 10305
Contact: Sean Taylor   
Principal Investigator: Marcin Kowalski, MD         
United States, Ohio
Cleveland Clinic Foundation Recruiting
Cleveland, Ohio, United States, 44195
Contact: Raquel Rozich, RN   
Principal Investigator: Niraj Varma, MD         
United States, Texas
Christus Trinity Mother Frances Health System Recruiting
Tyler, Texas, United States, 75702
Contact: Amanda Baker   
Principal Investigator: Stanislav Weiner, MD         
United States, Virginia
Virginia Commonwealth University Health System Recruiting
Richmond, Virginia, United States, 23219
Contact: Melissa Hockman   
Principal Investigator: Kenneth Ellenbogen, MD         
Sponsors and Collaborators
Boston Scientific Corporation
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Study Chair: Kenneth Ellenbogen, MD VCU Pauley Heart Center, Richmond, Virginia, USA
Principal Investigator: Arash Aryana, MD, PhD Mercy General Hospital,Sacramento, CA , USA
Principal Investigator: Nassir Marrouche, MD University of Utah School of Medicine. Slat Lake City, UT, USA
Principal Investigator: Ante Anić, MD University Hospital, Split, Croatia
Principal Investigator: Suneet Mittal, MD, FACC, FHRS Snyder AF Center, New York, NY, USA
Principal Investigator: Niraj Varma, MD, PhD, FRCP Cleveland Clinic, Cleveland OH, USA
Principal Investigator: Wilber W Su, MD, FACC, FHRS Banner- University Medical Group- Heart Center, Phoenix, AZ, USA
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Responsible Party: Boston Scientific Corporation Identifier: NCT04133168    
Other Study ID Numbers: PY004
First Posted: October 21, 2019    Key Record Dates
Last Update Posted: September 2, 2020
Last Verified: July 2020
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Undecided
Plan Description: No requests for study data have been made at this time, however Boston's Scientific's policy on data sharing can be found at

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: Yes
Device Product Not Approved or Cleared by U.S. FDA: Yes
Keywords provided by Boston Scientific Corporation:
Additional relevant MeSH terms:
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Atrial Fibrillation
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes