NCT03683030: STELLAR

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

Completed Phase 3 Results posted Last updated 20 October 2025

What this trial tests

Phase 3 trial testing Multi-Electrode RF Balloon Catheter in Atrial Fibrillation in 397 participants. Completed in 18 February 2022.

Timeline

22 October 2018

Primary endpoint
18 February 2022

18 February 2022

Quick facts

Lead sponsor	Biosense Webster, Inc.
Phase	Phase 3
Status	Completed
Study type	INTERVENTIONAL
Allocation	na
Design	single group
Masking	none
Primary purpose	treatment
Enrollment	397
Start date	22 October 2018
Primary completion	18 February 2022
Estimated completion	18 February 2022
Sites	41 locations across China, Italy, United States

Drugs / interventions tested

• Multi-Electrode RF Balloon Catheter

Conditions studied

• Atrial Fibrillation — all drugs for Atrial Fibrillation →

Sponsor

Biosense Webster, Inc. — full company profile →

Who can join

Adults 18 to 75, any sex, with Atrial Fibrillation. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Number of Participants With Any Primary Adverse Events (PAE) That Occurred Within 7 Days Following Atrial Fibrillation (AF) Ablation Procedure Using HELIOSTAR Catheter Primary · Within 7 days post-procedure (Day of procedure = Day 0)

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.

Group	Value	95% CI
Roll-in Phase	4
Main Study	13

Number of Participants With Effectiveness Success Primary · From Day 91 up to Day 365 post-procedure (Day of procedure = Day 0)

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) cardiover

Group	Value	95% CI
Roll-in Phase	62
Main Study	170

Percentage of Participants With Acute Procedural Success Secondary · Day 0 (day of procedure)

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).

Group	Value	95% CI
Roll-in Phase	100
Main Study	98.8

Percentage of Participants With Alternative 12-Month Success Secondary · From Day 91 up to Day 365 post-procedure (Day of procedure = Day 0)

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

Group	Value	95% CI
Roll-in Phase	67.7
Main Study	69.6

Percentage of Participants With 12-Month Symptomatic Recurrence Secondary · From Day 91 up to Day 365 post-procedure (Day of procedure = Day 0)

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) f

Group	Value	95% CI
Roll-in Phase	75.3
Main Study	74.3

Change From Baseline in Quality of Life as Assessed by Atrial Fibrillation Effect on Quality-of-Life (AFEQT) Scale Score Secondary · Baseline, Month 12

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

Group	Value	95% CI
Roll-in Phase	33.37	± 23.275
Main Study	35.90	± 21.754

Percentage of Participants With 12-Month Single Procedure Success Secondary · From Day 91 up to Day 365 post-procedure (Day of procedure = Day 0)

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 o

Group	Value	95% CI
Roll-in Phase	67.7
Main Study	68.4

Adverse events — posted to ClinicalTrials.gov

Time frame: From pre-procedure on Day 0 up to Month 12. Reporting threshold: 0%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

Roll-in Phase

Serious: 19/94 (20%)

Deaths: 0/117

Main Study

Serious: 50/260 (19%)

Deaths: 2/280

Serious adverse events (70 terms)

Reaction	System	Roll-in Phase	Main Study
Atrial fibrillation	Cardiac disorders	—	—
Atrial flutter	Cardiac disorders	—	—
Pericarditis	Cardiac disorders	—	—
Pericardial effusion	Cardiac disorders	—	—
Gastrointestinal haemorrhage	Gastrointestinal disorders	—	—
Nerve injury	Injury, poisoning and procedural complications	—	—
Electrocardiogram ST segment elevation	Investigations	—	—
Anaemia	Blood and lymphatic system disorders	—	—
Acute myocardial infarction	Cardiac disorders	—	—
Arrhythmia supraventricular	Cardiac disorders	—	—
Atrial tachycardia	Cardiac disorders	—	—
Cardiac failure	Cardiac disorders	—	—
Cardiac failure acute	Cardiac disorders	—	—
Sinus node dysfunction	Cardiac disorders	—	—
Myocardial infarction	Cardiac disorders	—	—
Diarrhoea	Gastrointestinal disorders	—	—
Gastric polyps	Gastrointestinal disorders	—	—
Melaena	Gastrointestinal disorders	—	—
Oesophageal ulcer	Gastrointestinal disorders	—	—
Rectal haemorrhage	Gastrointestinal disorders	—	—
Vomiting	Gastrointestinal disorders	—	—
Non-cardiac chest pain	General disorders	—	—
Pyrexia	General disorders	—	—
Chest pain	General disorders	—	—
Cholelithiasis	Hepatobiliary disorders	—	—

Other adverse events (175 terms — click to expand)

Reaction	System	Roll-in Phase	Main Study
Chest pain	General disorders	—	—
Atrial flutter	Cardiac disorders	—	—
Dyspnoea	Respiratory, thoracic and mediastinal disorders	—	—
Pyrexia	General disorders	—	—
Nausea	Gastrointestinal disorders	—	—
Corona virus infection	Infections and infestations	—	—
Headache	Nervous system disorders	—	—
Haematoma	Vascular disorders	—	—
Hypertension	Vascular disorders	—	—
Atrial fibrillation	Cardiac disorders	—	—
Diarrhoea	Gastrointestinal disorders	—	—
Blood pressure increased	Investigations	—	—
Hypokalaemia	Metabolism and nutrition disorders	—	—
Dysuria	Renal and urinary disorders	—	—
Atrial tachycardia	Cardiac disorders	—	—
Palpitations	Cardiac disorders	—	—
Sinus arrest	Cardiac disorders	—	—
Abdominal pain	Gastrointestinal disorders	—	—
Vomiting	Gastrointestinal disorders	—	—
Chest discomfort	General disorders	—	—
Fatigue	General disorders	—	—
Vessel puncture site haemorrhage	General disorders	—	—
Upper respiratory tract infection	Infections and infestations	—	—
Urinary tract infection	Infections and infestations	—	—
Vascular access site pain	Injury, poisoning and procedural complications	—	—
Oropharyngeal pain	Respiratory, thoracic and mediastinal disorders	—	—
Atrioventricular block first degree	Cardiac disorders	—	—
Pericardial effusion	Cardiac disorders	—	—
Sinus tachycardia	Cardiac disorders	—	—
Supraventricular tachycardia	Cardiac disorders	—	—
Supraventricular extrasystoles	Cardiac disorders	—	—
Conjunctival haemorrhage	Eye disorders	—	—
Visual impairment	Eye disorders	—	—
Chronic gastritis	Gastrointestinal disorders	—	—
Constipation	Gastrointestinal disorders	—	—
Sinusitis	Infections and infestations	—	—
Nerve injury	Injury, poisoning and procedural complications	—	—
Oesophageal injury	Injury, poisoning and procedural complications	—	—
Heart rate increased	Investigations	—	—
Back pain	Musculoskeletal and connective tissue disorders	—	—

Most-reported serious reactions: Atrial fibrillation, Atrial flutter, Pericarditis, Pericardial effusion, Gastrointestinal haemorrhage, Nerve injury, Electrocardiogram ST segment elevation, Anaemia.

Data from ClinicalTrials.gov NCT03683030 adverse events section.

Sponsor's own description

The primary objective of this clinical investigation is to demonstrate safety and effectiveness of the Multi-Electrode RF Balloon catheter for the treatment of drug refractory symptomatic paroxysmal atrial fibrillation.

Publications & conference data

2 peer-reviewed publications reference this trial (live from Europe PMC):

1. The Cutting Edge of Atrial Fibrillation Ablation.
   Verma MS, Terricabras M, Verma A. · · 2021 · cited 7× · PMID 34401182 · DOI 10.15420/aer.2020.40
2. Multielectrode Radiofrequency Balloon Catheter for Paroxysmal Atrial Fibrillation: Results From the Global, Multicenter, STELLAR Study.
   Goyal SK, Pappone C, Grimaldi M, Lee SW, et al · · 2025 · PMID 39686569 · DOI 10.1111/jce.16524