Trial Outcomes & Findings for Safety and Effectiveness Evaluation of the Multi-Electrode Radiofrequency Balloon Catheter for the Treatment of Symptomatic Paroxysmal Atrial Fibrillation (NCT NCT03683030)

Last Updated: 2025-10-17

Results Overview

An AE is any untoward medical occurrence in a participant whether or not related to the investigational medical device. PAEs included myocardial infarction, thromboembolism, transient ischemic attack, phrenic nerve paralysis, major vascular access complication/bleeding, pericarditis, pulmonary edema (respiratory insufficiency), stroke/cerebrovascular accident (CVA), hospitalization (initial or prolonged), device or procedure related death, atrio-esophageal fistula, pulmonary vein stenosis.

Recruitment status

COMPLETED

Study phase

PHASE3

Target enrollment

397 participants

Primary outcome timeframe

Within 7 days post-procedure (Day of procedure = Day 0)

Results posted on

2025-10-17

Participant Flow

As per protocol, enrolled participants who had signed informed consent form but did not meet eligibility criteria prior to insertion of the study catheter were considered as screen failures and excluded from analysis.

Participant milestones

Participant milestones
Measure	Roll-in Phase Participants enrolled in the roll-in phase with drug refractory, symptomatic paroxysmal atrial fibrillation (PAF) and were treated with the HELIOSTAR catheter in conjunction with the LassoStar catheter and Mutli-Channel radiofrequency (RF) Generator.	Main Study Participants enrolled in the main phase with drug refractory, symptomatic PAF, met eligibility criteria and had insertion of the HELIOSTAR catheter (with or without delivery of RF) in conjunction with the LassoStar catheter and Multi-Channel RF Generator.
Overall Study STARTED	117	280
Overall Study Evaluable Participants	94	260
Overall Study COMPLETED	93	249
Overall Study NOT COMPLETED	24	31

Reasons for withdrawal

Reasons for withdrawal
Measure	Roll-in Phase Participants enrolled in the roll-in phase with drug refractory, symptomatic paroxysmal atrial fibrillation (PAF) and were treated with the HELIOSTAR catheter in conjunction with the LassoStar catheter and Mutli-Channel radiofrequency (RF) Generator.	Main Study Participants enrolled in the main phase with drug refractory, symptomatic PAF, met eligibility criteria and had insertion of the HELIOSTAR catheter (with or without delivery of RF) in conjunction with the LassoStar catheter and Multi-Channel RF Generator.
Overall Study Enrolled but screen failures	12	7
Overall Study Enrolled but no catheter inserted	11	13
Overall Study Withdrawal by Subject	0	2
Overall Study Early termination by subject	1	0
Overall Study Lost to Follow-up	0	6
Overall Study Death	0	2
Overall Study Catheter inserted but did not undergo ablation	0	1

Baseline Characteristics

Safety and Effectiveness Evaluation of the Multi-Electrode Radiofrequency Balloon Catheter for the Treatment of Symptomatic Paroxysmal Atrial Fibrillation

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Roll-in Phase n=94 Participants Participants enrolled in the roll-in phase with drug refractory, symptomatic paroxysmal atrial fibrillation (PAF) and were treated with the HELIOSTAR catheter in conjunction with the LassoStar catheter and Mutli-Channel radiofrequency (RF) Generator.	Main Study n=257 Participants Participants enrolled in the main phase with drug refractory, symptomatic PAF, met eligibility criteria and had insertion of the HELIOSTAR catheter (with or without delivery of RF) in conjunction with the LassoStar catheter and Multi-Channel RF Generator.	Total n=351 Participants Total of all reporting groups
Age, Continuous	62.2 years STANDARD_DEVIATION 9.30 • n=5 Participants	60.1 years STANDARD_DEVIATION 9.13 • n=7 Participants	60.7 years STANDARD_DEVIATION 9.21 • n=5 Participants
Sex: Female, Male Female	36 Participants n=5 Participants	90 Participants n=7 Participants	126 Participants n=5 Participants
Sex: Female, Male Male	58 Participants n=5 Participants	167 Participants n=7 Participants	225 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	4 Participants n=5 Participants	36 Participants n=7 Participants	40 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	78 Participants n=5 Participants	193 Participants n=7 Participants	271 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	12 Participants n=5 Participants	28 Participants n=7 Participants	40 Participants n=5 Participants
Race/Ethnicity, Customized American Indian or Alaska Native	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race/Ethnicity, Customized Asian	5 Participants n=5 Participants	20 Participants n=7 Participants	25 Participants n=5 Participants
Race/Ethnicity, Customized Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race/Ethnicity, Customized Black or African American	2 Participants n=5 Participants	7 Participants n=7 Participants	9 Participants n=5 Participants
Race/Ethnicity, Customized White	80 Participants n=5 Participants	211 Participants n=7 Participants	291 Participants n=5 Participants
Race/Ethnicity, Customized Unknown or Not Reported	7 Participants n=5 Participants	19 Participants n=7 Participants	26 Participants n=5 Participants

PRIMARY outcome

Timeframe: Within 7 days post-procedure (Day of procedure = Day 0)

Population: Roll-in arm: Roll-in analysis set- participants who were enrolled in the roll-in phase and had undergone the radiofrequency (RF) delivery with the study catheters. Main study arm: Modified intent-to-treat (mITT) analysis set- enrolled participants who met eligibility criteria and had insertion of the Biosense Webster HELIOSTAR catheter. N (overall number of participants analyzed): participants evaluable for this outcome measure. Participants with missing values were excluded from the analysis.

Outcome measures

Outcome measures
Measure	Roll-in Phase n=94 Participants Participants enrolled in the roll-in phase with drug refractory, symptomatic paroxysmal atrial fibrillation (PAF) and were treated with the HELIOSTAR catheter in conjunction with the LassoStar catheter and Mutli-Channel radiofrequency (RF) Generator.	Main Study n=255 Participants Participants enrolled in the main phase with drug refractory, symptomatic PAF, met eligibility criteria and had insertion of the HELIOSTAR catheter (with or without delivery of RF) in conjunction with the LassoStar catheter and Multi-Channel RF Generator.
Number of Participants With Any Primary Adverse Events (PAE) That Occurred Within 7 Days Following Atrial Fibrillation (AF) Ablation Procedure Using HELIOSTAR Catheter	4 Participants	13 Participants

PRIMARY outcome

Timeframe: From Day 91 up to Day 365 post-procedure (Day of procedure = Day 0)

Population: Roll-in arm: Roll-in analysis set defined as all participants who were enrolled in the roll-in phase and had undergone the RF delivery with the study catheters. Main study arm: mITT analysis set defined as enrolled participants who met eligibility criteria and had insertion of the Biosense Webster HELIOSTAR catheter. Here, N (overall number of participants analyzed) signifies number of participants evaluable for this outcome measure.

Effectiveness success was defined as freedom from documented asymptomatic and symptomatic atrial fibrillation (AF), atrial tachycardia (AT), or atrial flutter (AFL; of unknown origin) episodes based on electrocardiographic data (greater than equal to \[\>=\] 30 seconds on arrhythmia monitoring device) through the effectiveness evaluation period (Day 91 through Day 365 post index procedure) and freedom from the following failure modes : freedom from acute procedural failure, freedom from non-study catheter failure, freedom from repeat ablation failure, freedom from direct Current (DC) cardioversion failure, freedom from recurrence (captured on 12-lead electrocardiogram \[ECG\]) failure, and freedom from anti-arrhythmic drug failure. AFL of unknown origin was defined as all AFL except those Cavo-Tricuspid Isthmus (CTI) dependent AFL as confirmed by accepted electrophysiology (EP) maneuvers (example, entrainment or activation mapping) in an EP study.

Outcome measures

Outcome measures
Measure	Roll-in Phase n=94 Participants Participants enrolled in the roll-in phase with drug refractory, symptomatic paroxysmal atrial fibrillation (PAF) and were treated with the HELIOSTAR catheter in conjunction with the LassoStar catheter and Mutli-Channel radiofrequency (RF) Generator.	Main Study n=250 Participants Participants enrolled in the main phase with drug refractory, symptomatic PAF, met eligibility criteria and had insertion of the HELIOSTAR catheter (with or without delivery of RF) in conjunction with the LassoStar catheter and Multi-Channel RF Generator.
Number of Participants With Effectiveness Success	62 Participants	170 Participants

SECONDARY outcome

Timeframe: Day 0 (day of procedure)

Population: Roll-in arm: Roll-in analysis set defined as all participants who were enrolled in the roll-in phase and had undergone the RF delivery with the study catheters. Main study arm: mITT analysis set defined as enrolled participants who met eligibility criteria and had insertion of the Biosense Webster HELIOSTAR catheter. Here, 'N' (number of participants analyzed) signifies participants evaluable for this outcome measure.

Acute procedural success is defined as confirmation of entrance block in clinically relevant pulmonary veins (PVs) (all PVs except those that were silent and/or could not be cannulated) after adenosine and/or isoproterenol challenge (with or without the use of a focal catheter).

Outcome measures

Outcome measures
Measure	Roll-in Phase n=94 Participants Participants enrolled in the roll-in phase with drug refractory, symptomatic paroxysmal atrial fibrillation (PAF) and were treated with the HELIOSTAR catheter in conjunction with the LassoStar catheter and Mutli-Channel radiofrequency (RF) Generator.	Main Study n=256 Participants Participants enrolled in the main phase with drug refractory, symptomatic PAF, met eligibility criteria and had insertion of the HELIOSTAR catheter (with or without delivery of RF) in conjunction with the LassoStar catheter and Multi-Channel RF Generator.
Percentage of Participants With Acute Procedural Success	100 percentage of participants	98.8 percentage of participants

SECONDARY outcome

Timeframe: From Day 91 up to Day 365 post-procedure (Day of procedure = Day 0)

Population: Roll-in arm: Roll-in analysis set defined as all participants who were enrolled in the roll-in phase and had undergone the RF delivery with the study catheters. Main study arm: mITT analysis set defined as enrolled participants who met eligibility criteria and had insertion of the Biosense Webster HELIOSTAR catheter. Here, 'N' (number of participants analyzed) signifies participants evaluable for this outcome measure.

Alternative 12-month success is defined as freedom from documented symptomatic AF/AT/AFL (of unknown origin) episodes based on electrocardiographic data (\>=30 seconds on arrhythmia monitoring device) through the effectiveness evaluation period (Day 91 through Day 365) and freedom from the following failure modes: freedom from acute procedural failure, freedom from non-study catheter failure, freedom from repeat ablation failure, freedom from DC Cardioversion failure, freedom from recurrence (captured on 12-lead ECG) failure, and freedom from anti-arrhythmic drug failure. AFL of unknown origin is defined as all AFL except those CTI dependent AFL as confirmed by accepted EP maneuvers (e.g. entrainment or activation mapping) in an EP study.

Outcome measures

Outcome measures
Measure	Roll-in Phase n=93 Participants Participants enrolled in the roll-in phase with drug refractory, symptomatic paroxysmal atrial fibrillation (PAF) and were treated with the HELIOSTAR catheter in conjunction with the LassoStar catheter and Mutli-Channel radiofrequency (RF) Generator.	Main Study n=250 Participants Participants enrolled in the main phase with drug refractory, symptomatic PAF, met eligibility criteria and had insertion of the HELIOSTAR catheter (with or without delivery of RF) in conjunction with the LassoStar catheter and Multi-Channel RF Generator.
Percentage of Participants With Alternative 12-Month Success	67.7 percentage of participants	69.6 percentage of participants

SECONDARY outcome

Timeframe: From Day 91 up to Day 365 post-procedure (Day of procedure = Day 0)

Population: Roll-in arm: Roll-in analysis set defined as all participants who were enrolled in the roll-in phase and had undergone the RF delivery with the study catheters. Main study arm: mITT analysis set defined as enrolled participants who met eligibility criteria and had insertion of the Biosense Webster HELIOSTAR catheter. Here, 'N' (number of participants analyzed) signifies participants evaluable for this outcome measure.

12-month symptomatic recurrence endpoint is defined as freedom from documented symptomatic AF/AT/AFL (of unknown origin) episodes based on electrocardiographic data (\>=30 seconds on arrhythmia monitoring device) through the effectiveness evaluation period (Day 91 through Day 365) in participants regardless of antiarrhythmic drug (AAD) use and freedom from the following failure modes: freedom from acute procedural failure, freedom from non-study catheter failure, freedom from repeat ablation failure, freedom from DC Cardioversion failure, and freedom from recurrence (captured on 12-lead ECG) failure. AFL of unknown origin is defined as all AFL except those CTI dependent AFL as confirmed by accepted EP maneuvers (e.g. entrainment or activation mapping) in an EP study.

Outcome measures

Outcome measures
Measure	Roll-in Phase n=93 Participants Participants enrolled in the roll-in phase with drug refractory, symptomatic paroxysmal atrial fibrillation (PAF) and were treated with the HELIOSTAR catheter in conjunction with the LassoStar catheter and Mutli-Channel radiofrequency (RF) Generator.	Main Study n=249 Participants Participants enrolled in the main phase with drug refractory, symptomatic PAF, met eligibility criteria and had insertion of the HELIOSTAR catheter (with or without delivery of RF) in conjunction with the LassoStar catheter and Multi-Channel RF Generator.
Percentage of Participants With 12-Month Symptomatic Recurrence	75.3 percentage of participants	74.3 percentage of participants

SECONDARY outcome

Timeframe: Baseline, Month 12

Population: Roll-in arm: Roll-in analysis set defined as all participants who were enrolled in the roll-in phase and had undergone the RF delivery with the study catheters. Main study arm: mITT analysis set defined as enrolled participants who met eligibility criteria and had insertion of the Biosense Webster HELIOSTAR catheter. Here, 'N' (number of participants analyzed): participants evaluable for this outcome measure.

AFEQT questionnaire is an atrial fibrillation-specific health-related quality of life (HRQoL) questionnaire designed to assess the impact of atrial fibrillation on participant's HRQoL. The questionnaire includes 20 questions on a 7-point Likert scale. Questions 1 to 18 evaluated HRQoL and questions 19 to 20 related to participant's satisfaction with treatment. Overall scores ranged from 0 to 100, where 0 corresponds to complete disability (or responding "extremely" limited, difficult or bothersome to all questions answered), while a score of 100 corresponds to no disability (or responding "not at all" limited, difficult or bothersome to all questions answered). Therefore, a positive change in score corresponds to improvement in QoL. Total score was calculated using AFEQT formula: 100 minus (\[sum of severity for all questions answered minus number of questions answered\]\*100 / total number questions answered\*6).

Outcome measures

Outcome measures
Measure	Roll-in Phase n=94 Participants Participants enrolled in the roll-in phase with drug refractory, symptomatic paroxysmal atrial fibrillation (PAF) and were treated with the HELIOSTAR catheter in conjunction with the LassoStar catheter and Mutli-Channel radiofrequency (RF) Generator.	Main Study n=237 Participants Participants enrolled in the main phase with drug refractory, symptomatic PAF, met eligibility criteria and had insertion of the HELIOSTAR catheter (with or without delivery of RF) in conjunction with the LassoStar catheter and Multi-Channel RF Generator.
Change From Baseline in Quality of Life as Assessed by Atrial Fibrillation Effect on Quality-of-Life (AFEQT) Scale Score	33.37 score on a scale Standard Deviation 23.275	35.90 score on a scale Standard Deviation 21.754

SECONDARY outcome

Timeframe: From Day 91 up to Day 365 post-procedure (Day of procedure = Day 0)

Population: Roll-in arm: Roll-in analysis set defined as all participants who were enrolled in the roll-in phase and had undergone the RF delivery with the study catheters. Main study arm: mITT analysis set defined as enrolled participants who met eligibility criteria and had insertion of the Biosense Webster HELIOSTAR catheter. Here, 'N' (number of participants analyzed) signifies participants evaluable for this outcome measure.

12-month single procedure success is defined as freedom from documented symptomatic AF/AT/AFL (of unknown origin) episodes based on electrocardiographic data (\>=30 seconds on arrhythmia monitoring device) through the effectiveness evaluation period (Day 91 through Day 365) and freedom from the following failure modes: freedom from acute procedural failure, freedom from non-study catheter failure, freedom from repeat ablation failure, freedom from DC Cardioversion failure, freedom from recurrence (captured on 12-lead ECG) failure, and freedom from anti-arrhythmic drug failure. AFL of unknown origin is defined as all AFL except those CTI dependent AFL as confirmed by accepted EP maneuvers (e.g. entrainment or activation mapping) in an EP study.

Outcome measures

Outcome measures
Measure	Roll-in Phase n=93 Participants Participants enrolled in the roll-in phase with drug refractory, symptomatic paroxysmal atrial fibrillation (PAF) and were treated with the HELIOSTAR catheter in conjunction with the LassoStar catheter and Mutli-Channel radiofrequency (RF) Generator.	Main Study n=250 Participants Participants enrolled in the main phase with drug refractory, symptomatic PAF, met eligibility criteria and had insertion of the HELIOSTAR catheter (with or without delivery of RF) in conjunction with the LassoStar catheter and Multi-Channel RF Generator.
Percentage of Participants With 12-Month Single Procedure Success	67.7 percentage of participants	68.4 percentage of participants

Adverse Events

Roll-in Phase

Serious events: 19 serious events

Other events: 42 other events

Deaths: 0 deaths

Main Study

Serious events: 50 serious events

Other events: 97 other events

Deaths: 2 deaths

Serious adverse events

Other adverse events

Additional Information

Senior Director Clinical Research

Biosense Webster, Inc.

Phone: 844-434-4210

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee All information concerning the study, investigational medical device, sponsor operations, patent application, manufacturing processes, and basic scientific data supplied by the sponsor to the investigator and not previously published, are considered confidential and remain the sole property of the sponsor.
Publication restrictions are in place

Restriction type: OTHER