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Boston Scientific's Cryoballoon in the Treatment of Symptomatic Drug Refractory Paroxysmal Atrial Fibrillation

Safety and Effectiveness IDE Trial for Boston Scientific's Cryoballoon in the Treatment of Symptomatic Drug Refractory Paroxysmal Atrial Fibrillation

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04133168
Acronym
FROZEN-AF
Enrollment
458
Registered
2019-10-21
Start date
2020-06-24
Completion date
2023-08-17
Last updated
2025-04-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Paroxysmal Atrial Fibrillation

Keywords

cryoablation

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).

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.

Interventions

The Boston Scientific 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 main devices and components of the system consists of the following: * POLARx™ or POLARx™ FIT Cryoablation Catheter * POLARMAP™ Catheter * POLARSHEATH™ * SMARTFREEZE™ Console * Diaphragm Movement Sensor (DMS) * Related Accessories

Sponsors

Boston Scientific Corporation
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Intervention model description

open label, prospective, single arm study

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* History of recurrent symptomatic paroxysmal atrial fibrillation (PAF), defined as atrial fibrillation that terminates spontaneously or with intervention (either procedure or drug therapy) within seven days of onset. Minimum documentation includes the following: * a physician's note indicating recurrent self-terminating atrial fibrillation (AF) which includes at least two symptomatic AF episodes within six months prior to enrollment, and one electrocardiographically documented AF episode within 12 months prior to enrollment. * 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; * 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.

Design outcomes

Primary

MeasureTime frameDescription
Percentage of Participants With Acute Procedural Success Defined as the Achievement of Electrical Isolation of All PVs by Using the Boston Scientific Cardiac Cryoablation System With POLARx Fit Cryoablation Balloon Catheter Models1 dayThe primary effectiveness endpoint is the rate of acute procedural success where acute procedural success is defined as the achievement of electrical isolation of all PVs by using the Cardiac Cryoablation System with the POLARx FIT cryoablation balloon catheter models (with treatment applied at 28 mm or 31 mm balloon size per physician discretion). Electrical isolation of a PV is demonstrated by entrance and exit block.
Percentage of Participants With Freedom From Primary Safety Events at 12 Months Post-procedure (Acute and Chronic Events) Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models12 MonthsThis measure reports the observed safety event-free rate at 12 Months follow up for all Non Roll-In treatment and intent subjects. The safety events are a 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 .
Percentage of Participants With Freedom From Treatment Failure at 12 Months Post-procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models12 MonthsFreedom from the composite of: Failure to achieve acute procedural success in the index procedure or repeat procedure during the blanking period; Use of amiodarone post index procedure; Surgical treatment for AF/AFL/AT post index procedure; Use of non-study ablation catheter for AF targets in the index procedure or repeat procedure during the blanking period; More than one repeat procedure with the POLARx catheter during the blanking period (90 days post index procedure); Documented AF, or new onset of AF or AT event 91-365 days post index procedure; Any of the following for AF, or new onset of AF or AT 91-365 days post index procedure: Repeat procedure - Electrical and/or pharmacological cardioversion for AF/AFL/AT - Prescribed AAD consisting of any Class I/III, including Amiodarone, and any Class II/IV medications taken for control of AF, AT, AFL recurrence
Percentage of Participants With Freedom From Primary Safety Events at 3 Months Post Procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx FIT Cryoablation Balloon Catheter Models3 monthsComposite of procedure-related and device-related adverse events. 7 days post index procedure or hospital discharge, whichever is later, unless denoted as events counting through 3 months post index procedure (Death, Myocardial infarction, Major Vagal Nerve Injury/Gastroparesis, Transient ischemic attack, Stroke/Cerebrovascular accident, Thromboembolism, Cardiac tamponade/perforation, Pneumothorax, Major vascular access complications, Pulmonary edema/heart failure, AV block, Atrial esophageal fistula, severe pulmonary vein stenosis (≥70% reduction in the diameter of the PV or PV branch from baseline), Persistent phrenic nerve palsy)

Secondary

MeasureTime frameDescription
Percentage of Participants With Freedom From Treatment Failure at 12 Months Post-procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx FIT Cryoablation Balloon Catheter Models12 MonthsFreedom from the composite of: Failure to achieve acute procedural success in the index procedure or repeat procedure during the blanking period; Use of amiodarone post index procedure; Surgical treatment for AF/AFL/AT post index procedure; Use of non-study ablation catheter for AF targets in the index procedure or repeat procedure during the blanking period; More than one repeat procedure with the Cryoablation System during the blanking period (90 days post index procedure); Documented AF, or new onset of AF or AT event 91-365 days post index procedure; Any of the following for AF, or new onset of AF or AT 91-365 days post index procedure: Repeat procedure - Electrical and/or pharmacological cardioversion for AF/AFL/AT - Prescribed AAD consisting of any Class I/III, including Amiodarone, and any Class II/IV medications taken for control of AF, AT, AFL recurrence
Percentage of Participants With Acute Procedural Success Defined as the Achievement of Electrical Isolation of All PVs by Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter1 dayThe achievement of electrical isolation of all PVs by using the POLARx Cardiac Cryoablation System. Electrical isolation of a PV is demonstrated by entrance and exit block.
Number of Participants With Freedom From Reportable Adverse Events at 12 Months Post Procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models12 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
Percentage of Participants With Freedom From Safety Events at 12 Months Post Procedure Using the Boston Scientific Cardiac Cryoablation System Using the Boston Scientific Cardiac Cryoablation System With POLARx FIT Cryoablation Balloon Catheter Models12 MonthsThe following events will be counted through 7 days post index procedure or hospital discharge, whichever is later: Death, Myocardial infarction, Major Vagal Nerve Injury/Gastroparesis, Transient ischemic attack, Stroke/Cerebrovascular accident, Thromboembolism, Pneumothorax, Major vascular access complications, Pulmonary edema/heart failure, AV block. The following event will be counted through 30 days post index procedure: Cardiac tamponade/perforation. The following events will be counted through 12 months post index procedure: Atrial esophageal fistula, Severe pulmonary vein stenosis (≥70% reduction in the diameter of the PV or PV branch from baseline), Persistent phrenic nerve palsy.

Other

MeasureTime frameDescription
Percentage of Participants With Freedom From Recurrence12 MonthsThe following analysis looks at the recurrence free rate of individual atrial arrhythmia types as documented on a rhythm monitoring device post- blanking period.

Countries

Belgium, Canada, France, Germany, Hong Kong, Italy, Netherlands, Taiwan, United States

Participant flow

Participants by arm

ArmCount
FROzEN Non Roll-In Treatment Subjects
Subjects undergoing cardiac ablation procedure with the Boston Scientific Cardiac Cryoablation System Boston Scientific Cardiac Cryoablation System: The Boston Scientific 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 main devices and components of the system consists of the following: * POLARx™ or POLARx FIT Cryoablation Catheter * POLARMAP™ Catheter * POLARSHEATH™ * SMARTFREEZE™ Console * Diaphragm Movement Sensor (DMS) * Related Accessories
325
POLARx FIT Sub-study
Subjects undergoing cardiac ablation procedure with the Boston Scientific Cardiac Cryoablation System Boston Scientific Cardiac Cryoablation System: The Boston Scientific 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 main devices and components of the system consists of the following: * POLARx™ or POLARx FIT Cryoablation Catheter * POLARMAP™ Catheter * POLARSHEATH™ * SMARTFREEZE™ Console * Diaphragm Movement Sensor (DMS) * Related Accessories
50
Total375

Baseline characteristics

CharacteristicTotalPOLARx FIT Sub-studyFROzEN Non Roll-In Treatment Subjects
Age, Continuous62 years
STANDARD_DEVIATION 11
64 years
STANDARD_DEVIATION 13
62 years
STANDARD_DEVIATION 11
BMI29 kg/m^2
STANDARD_DEVIATION 6
31 kg/m^2
STANDARD_DEVIATION 7
29 kg/m^2
STANDARD_DEVIATION 6
CHA2DS2-VASc Score
0
66 Participants3 Participants63 Participants
CHA2DS2-VASc Score
1
97 Participants15 Participants82 Participants
CHA2DS2-VASc Score
2
108 Participants16 Participants92 Participants
CHA2DS2-VASc Score
3
64 Participants5 Participants59 Participants
CHA2DS2-VASc Score
4
27 Participants6 Participants21 Participants
CHA2DS2-VASc Score
5
12 Participants4 Participants8 Participants
CHA2DS2-VASc Score
6
1 Participants1 Participants0 Participants
Diastolic BP79 mmHg
STANDARD_DEVIATION 11
76 mmHg
STANDARD_DEVIATION 9
79 mmHg
STANDARD_DEVIATION 11
Height174 cm
STANDARD_DEVIATION 10
173 cm
STANDARD_DEVIATION 10
174 cm
STANDARD_DEVIATION 10
Pulse67 bpm
STANDARD_DEVIATION 14
66 bpm
STANDARD_DEVIATION 13
67 bpm
STANDARD_DEVIATION 14
Race/Ethnicity, Customized
Asian
35 Participants0 Participants35 Participants
Race/Ethnicity, Customized
Black
5 Participants1 Participants4 Participants
Race/Ethnicity, Customized
Hispanic or Latino
5 Participants0 Participants5 Participants
Race/Ethnicity, Customized
Native American
1 Participants0 Participants1 Participants
Race/Ethnicity, Customized
Other
1 Participants0 Participants1 Participants
Race/Ethnicity, Customized
Pacific Islander
0 Participants0 Participants0 Participants
Race/Ethnicity, Customized
Race Undisclosed
12 Participants0 Participants12 Participants
Race/Ethnicity, Customized
White
323 Participants49 Participants274 Participants
Sex: Female, Male
Female
147 Participants23 Participants124 Participants
Sex: Female, Male
Male
228 Participants27 Participants201 Participants
Systolic BP133 mmHg
STANDARD_DEVIATION 18
134 mmHg
STANDARD_DEVIATION 16
133 mmHg
STANDARD_DEVIATION 18
Weight87 kg
STANDARD_DEVIATION 20
93 kg
STANDARD_DEVIATION 22
86 kg
STANDARD_DEVIATION 19

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
1 / 3361 / 600 / 50
other
Total, other adverse events
86 / 32616 / 605 / 50
serious
Total, serious adverse events
33 / 32610 / 604 / 50

Outcome results

Primary

Percentage of Participants With Acute Procedural Success Defined as the Achievement of Electrical Isolation of All PVs by Using the Boston Scientific Cardiac Cryoablation System With POLARx Fit Cryoablation Balloon Catheter Models

The primary effectiveness endpoint is the rate of acute procedural success where acute procedural success is defined as the achievement of electrical isolation of all PVs by using the Cardiac Cryoablation System with the POLARx FIT cryoablation balloon catheter models (with treatment applied at 28 mm or 31 mm balloon size per physician discretion). Electrical isolation of a PV is demonstrated by entrance and exit block.

Time frame: 1 day

ArmMeasureValue (NUMBER)
FROzEN Non Roll-In SubjectsPercentage of Participants With Acute Procedural Success Defined as the Achievement of Electrical Isolation of All PVs by Using the Boston Scientific Cardiac Cryoablation System With POLARx Fit Cryoablation Balloon Catheter Models100 Percentage of participants
Primary

Percentage of Participants With Freedom From Primary Safety Events at 12 Months Post-procedure (Acute and Chronic Events) Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models

This measure reports the observed safety event-free rate at 12 Months follow up for all Non Roll-In treatment and intent subjects. The safety events are a 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 .

Time frame: 12 Months

Population: Non Roll-In Treatment and intent Subjects

ArmMeasureValue (NUMBER)
FROzEN Non Roll-In SubjectsPercentage of Participants With Freedom From Primary Safety Events at 12 Months Post-procedure (Acute and Chronic Events) Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models96 Percentage of participants
Primary

Percentage of Participants With Freedom From Primary Safety Events at 3 Months Post Procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx FIT Cryoablation Balloon Catheter Models

Composite of procedure-related and device-related adverse events. 7 days post index procedure or hospital discharge, whichever is later, unless denoted as events counting through 3 months post index procedure (Death, Myocardial infarction, Major Vagal Nerve Injury/Gastroparesis, Transient ischemic attack, Stroke/Cerebrovascular accident, Thromboembolism, Cardiac tamponade/perforation, Pneumothorax, Major vascular access complications, Pulmonary edema/heart failure, AV block, Atrial esophageal fistula, severe pulmonary vein stenosis (≥70% reduction in the diameter of the PV or PV branch from baseline), Persistent phrenic nerve palsy)

Time frame: 3 months

ArmMeasureValue (NUMBER)
FROzEN Non Roll-In SubjectsPercentage of Participants With Freedom From Primary Safety Events at 3 Months Post Procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx FIT Cryoablation Balloon Catheter Models100 Percentage of participants
Primary

Percentage of Participants With Freedom From Treatment Failure at 12 Months Post-procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models

Freedom from the composite of: Failure to achieve acute procedural success in the index procedure or repeat procedure during the blanking period; Use of amiodarone post index procedure; Surgical treatment for AF/AFL/AT post index procedure; Use of non-study ablation catheter for AF targets in the index procedure or repeat procedure during the blanking period; More than one repeat procedure with the POLARx catheter during the blanking period (90 days post index procedure); Documented AF, or new onset of AF or AT event 91-365 days post index procedure; Any of the following for AF, or new onset of AF or AT 91-365 days post index procedure: Repeat procedure - Electrical and/or pharmacological cardioversion for AF/AFL/AT - Prescribed AAD consisting of any Class I/III, including Amiodarone, and any Class II/IV medications taken for control of AF, AT, AFL recurrence

Time frame: 12 Months

ArmMeasureValue (NUMBER)
FROzEN Non Roll-In SubjectsPercentage of Participants With Freedom From Treatment Failure at 12 Months Post-procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models59.9 Percentage of participants
Secondary

Number of Participants With Freedom From Reportable Adverse Events at 12 Months Post Procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models

* 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

Time frame: 12 months

Population: The total population represents all Non-Roll In (336) and Roll in (63) enrolled subjects.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
FROzEN Non Roll-In SubjectsNumber of Participants With Freedom From Reportable Adverse Events at 12 Months Post Procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models254 Participants
Secondary

Percentage of Participants With Acute Procedural Success Defined as the Achievement of Electrical Isolation of All PVs by Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter

The achievement of electrical isolation of all PVs by using the POLARx Cardiac Cryoablation System. Electrical isolation of a PV is demonstrated by entrance and exit block.

Time frame: 1 day

ArmMeasureValue (NUMBER)
FROzEN Non Roll-In SubjectsPercentage of Participants With Acute Procedural Success Defined as the Achievement of Electrical Isolation of All PVs by Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter95.69 Percentage of participants
Secondary

Percentage of Participants With Freedom From Safety Events at 12 Months Post Procedure Using the Boston Scientific Cardiac Cryoablation System Using the Boston Scientific Cardiac Cryoablation System With POLARx FIT Cryoablation Balloon Catheter Models

The following events will be counted through 7 days post index procedure or hospital discharge, whichever is later: Death, Myocardial infarction, Major Vagal Nerve Injury/Gastroparesis, Transient ischemic attack, Stroke/Cerebrovascular accident, Thromboembolism, Pneumothorax, Major vascular access complications, Pulmonary edema/heart failure, AV block. The following event will be counted through 30 days post index procedure: Cardiac tamponade/perforation. The following events will be counted through 12 months post index procedure: Atrial esophageal fistula, Severe pulmonary vein stenosis (≥70% reduction in the diameter of the PV or PV branch from baseline), Persistent phrenic nerve palsy.

Time frame: 12 Months

ArmMeasureValue (NUMBER)
FROzEN Non Roll-In SubjectsPercentage of Participants With Freedom From Safety Events at 12 Months Post Procedure Using the Boston Scientific Cardiac Cryoablation System Using the Boston Scientific Cardiac Cryoablation System With POLARx FIT Cryoablation Balloon Catheter Models100 Percentage of participants
Secondary

Percentage of Participants With Freedom From Treatment Failure at 12 Months Post-procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx FIT Cryoablation Balloon Catheter Models

Freedom from the composite of: Failure to achieve acute procedural success in the index procedure or repeat procedure during the blanking period; Use of amiodarone post index procedure; Surgical treatment for AF/AFL/AT post index procedure; Use of non-study ablation catheter for AF targets in the index procedure or repeat procedure during the blanking period; More than one repeat procedure with the Cryoablation System during the blanking period (90 days post index procedure); Documented AF, or new onset of AF or AT event 91-365 days post index procedure; Any of the following for AF, or new onset of AF or AT 91-365 days post index procedure: Repeat procedure - Electrical and/or pharmacological cardioversion for AF/AFL/AT - Prescribed AAD consisting of any Class I/III, including Amiodarone, and any Class II/IV medications taken for control of AF, AT, AFL recurrence

Time frame: 12 Months

ArmMeasureValue (NUMBER)
FROzEN Non Roll-In SubjectsPercentage of Participants With Freedom From Treatment Failure at 12 Months Post-procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx FIT Cryoablation Balloon Catheter Models78 Percentage of participants
Other Pre-specified

Percentage of Participants With Freedom From Recurrence

The following analysis looks at the recurrence free rate of individual atrial arrhythmia types as documented on a rhythm monitoring device post- blanking period.

Time frame: 12 Months

ArmMeasureValue (NUMBER)
FROzEN Non Roll-In SubjectsPercentage of Participants With Freedom From Recurrence79.9 Percentage of participants
Post Hoc

Percentage of Participants With Freedom From Treatment Failure With Updated AAD Definition at 12 Months Post-procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models

In this sensitivity analysis, subjects were counted as primary effectiveness failures only if they were taking a new AAD not prescribed prior to index procedure or a higher dose of an AAD than they were previously prescribed.

Time frame: 12 Months

ArmMeasureValue (NUMBER)
FROzEN Non Roll-In SubjectsPercentage of Participants With Freedom From Treatment Failure With Updated AAD Definition at 12 Months Post-procedure Using the Boston Scientific Cardiac Cryoablation System With POLARx Cryoablation Balloon Catheter Models71.6 Percentage of participants

Source: ClinicalTrials.gov · Data processed: Feb 6, 2026