An interventional study of VARIPULSE Pulsed Field Ablation System and Pulmonary Vein Isolation in Atrial Fibrillation (AF), sponsored by China National Center for Cardiovascular Diseases. Not yet recruiting at 1 site in China. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-11-09.
Sponsored by China National Center for Cardiovascular Diseases · Not applicable, Interventional, and Treatment
UNI-PFA is a multicenter, randomized, open-label, superiority trial evaluating whether adding unipolar voltage-guided individualized substrate modification to pulsed field ablation (PFA)-based pulmonary vein isolation (PVI) improves outcomes in patients with persistent atrial fibrillation and a left atrial low-voltage area (LVA) burden of at least 10% of the post-PVI left atrial surface area. Participants are randomized 1:1 to PFA-PVI plus individualized substrate modification (homogenization, box isolation, linear ablation, or a combination) or PFA-PVI alone. The primary endpoint is treatment success at 12 months, defined as freedom from documented atrial fibrillation, atrial tachycardia, or atrial flutter lasting more than 30 seconds after a 90-day blanking period while off class I/III antiarrhythmic drugs. Follow-up includes 14-day continuous ECG patch monitoring at 3, 6, and 12 months, symptom-triggered single-lead ECG, and quality-of-life assessments.
Background: Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation for atrial fibrillation, but outcomes in persistent atrial fibrillation remain suboptimal, with approximately 50% freedom from recurrence in unselected patients. Left atrial low-voltage areas (LVAs) are an electrical surrogate for atrial fibrosis and predict recurrence after PVI. Unipolar voltage mapping may detect intramural or epicardial fibrosis that bipolar mapping misses. Pulsed field ablation (PFA) provides preferential myocardial ablation with a favorable safety profile. Whether adding unipolar voltage-guided individualized substrate modification to PFA-PVI improves outcomes in patients with a substantial LVA burden is unknown.
Design: UNI-PFA is a multicenter, randomized, open-label, superiority trial. Approximately 294 participants with persistent or long-standing persistent atrial fibrillation and a unipolar LVA burden of at least 10% of the post-PVI left atrial surface area (excluding the pulmonary vein antra, left atrial appendage, and fossa ovalis) will be randomized 1:1. Randomization is stratified by sex and LVA proportion category (10-20%, 20-30%, and >30%). The experimental arm receives PFA-PVI plus individualized substrate modification selected according to LVA location (homogenization, box isolation, linear ablation, or a combination); the active comparator arm receives PFA-PVI alone. All participants receive 14-day continuous ECG patch monitoring at 3, 6, and 12 months, symptom-triggered single-lead ECG, and unscheduled ECG/Holter/telemetry when clinically indicated.
Endpoints: The primary endpoint is treatment success at 12 months, defined as freedom from documented atrial fibrillation, atrial tachycardia, or atrial flutter lasting more than 30 seconds after a 90-day blanking period while off class I/III antiarrhythmic drugs, allowing up to one repeat ablation within 6 months of the index procedure. Patients who remain on class I/III antiarrhythmic drugs at 12 months are counted as treatment failures. Twelve prespecified secondary endpoints include arrhythmia-free survival, quality of life (AFEQT), arrhythmia burden, repeat ablation, procedure duration, and fluoroscopy time. Sixteen prespecified safety endpoints are adjudicated by an independent, blinded clinical events committee.
Eligibility: Adults aged 18 years or older with symptomatic persistent or long-standing persistent atrial fibrillation, suitable for catheter ablation, who have tried at least one class I/III antiarrhythmic drug or are unwilling to do so, and who meet the intraoperative unipolar LVA criterion. Key exclusions include left atrial diameter >55 mm, recent acute coronary syndrome or coronary artery bypass grafting, severe valvular disease, prior atrial fibrillation ablation or left atrial surgery, NYHA class IV heart failure, contraindication to oral anticoagulation, dialysis-dependent renal failure, and pregnancy.
4,009 studies on the registry are indexed under Atrial Fibrillation; 961 are open to participants now.
This study's planned enrollment of 294 is above the median of 150 across 2,476 interventional studies indexed under Atrial Fibrillation.
Browse Atrial Fibrillation studies →China National Center for Cardiovascular Diseases is the lead sponsor of 269 studies on the registry; 141 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Pulsed field ablation (PFA)-based pulmonary vein isolation plus unipolar voltage-guided individualized substrate modification. Substrate modification is selected according to low-voltage area location and may include homogenization, box isolation, linear ablation, or a combination.
Device: VARIPULSE Pulsed Field Ablation System · Procedure: Pulmonary Vein Isolation · Procedure: Individualized Substrate Modification
Pulsed field ablation (PFA)-based pulmonary vein isolation alone, without substrate or prophylactic ablation.
Device: VARIPULSE Pulsed Field Ablation System · Procedure: Pulmonary Vein Isolation
Pulsed field ablation catheter and generator used to perform pulmonary vein isolation in both study arms.
Pulsed field ablation-based pulmonary vein antral isolation with confirmation of entrance and exit block in all pulmonary veins; performed in both arms.
Unipolar voltage-guided individualized substrate modification selected according to low-voltage area location, including homogenization, box isolation, linear ablation, or a combination. Performed in the experimental arm only.
Treatment Success at 12 Months After the Index Ablation Procedure
Freedom from documented atrial fibrillation, atrial tachycardia, or atrial flutter lasting more than 30 seconds after a 90-day blanking period while off class I/III antiarrhythmic drugs, allowing up to one repeat ablation within 6 months of the index procedure (1-2 procedures total). Patients who remain on class I/III antiarrhythmic drugs at 12 months are counted as treatment failures; missing primary outcome data are counted as treatment failures.
Time frame: 12 months after the index ablation procedure
Time to First Recurrence After a Single Procedure Off Antiarrhythmic Drugs
Time frame: 12 months after the index procedure
Change in AFEQT Quality-of-Life Score From Baseline to 12 Months
Time frame: Baseline and 12 months
Incidence of Prespecified Procedure-Related Complications
Time frame: 90 days after ablation; all-cause mortality at 12 months
Freedom From Atrial Arrhythmia at 12 Months After a Single Procedure Off Antiarrhythmic Drugs
Time frame: 12 months
Freedom From Atrial Arrhythmia at 12 Months After a Single Procedure With or Without Antiarrhythmic Drugs
Time frame: 12 months
Freedom From Atrial Arrhythmia at 12 Months After 1-2 Procedures With or Without Antiarrhythmic Drugs
Time frame: 12 months
Freedom From Atrial Fibrillation at 12 Months After 1-2 Procedures Off Antiarrhythmic Drugs
Time frame: 12 months
Atrial Arrhythmia Burden at 3, 6, and 12 Months
Time frame: 14-day period before each follow-up visit
Time to First Recurrence After Any Number of Procedures
Time frame: 12 months
Number of Repeat Ablations Within 12 Months
Time frame: 12 months after the index procedure
Procedure Duration
Time frame: Index procedure
Total Fluoroscopy Time
Time frame: Index procedure
Plan to share: No — Individual participant data will not be shared. Aggregate study results will be published and presented. The informed consent and institutional data-governance approvals do not permit public deposition of individual participant data.
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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