Pulsed-Field Ablation for Recurrent Atypical Atrial Flutter

NCT07362134 | Enrolling By Invitation DMC

• 1 other identifier: 2025-09-005C
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Recurrent atypical atrial flutter (AFL) after prior atrial fibrillation or flutter ablation remains challenging to treat, and conventional radiofrequency ablation may be limited by incomplete lesion formation and risk of collateral damage. Pulsed-field ablation (PFA) uses non-thermal electric fields to create myocardial lesions with relative sparing of surrounding tissues and may improve the safety and efficacy of ablation for atypical AFL. This prospective, non-randomized, single-arm study will enroll approximately 30 patients with clinically documented recurrent atypical AFL who are referred for elective catheter ablation using a point-by-point pulsed-field ablation system. During the index procedure, detailed electroanatomic mapping will be performed to identify the critical isthmus or circuit, followed by linear or focal PFA and confirmation of bidirectional conduction block. The primary safety endpoint is the incidence of procedure- and device-related primary adverse events. The primary effectiveness endpoint is acute procedural success, defined as termination of atypical AFL and establishment of bidirectional block across the targeted lesion set at the end of the procedure. Secondary endpoints include recurrence of any atrial arrhythmia during 12-month follow-up, durability of the linear lesions assessed by repeat electroanatomic mapping at 3 months, changes in atrial scar on cardiac MRI, peri-procedural changes in blood biomarkers, and the rate of serious adverse events related to the procedure or study device.

Conditions

Atypical Atrial Flutter; Atrial Flutter

Keywords

Atypical atrial flutter; Recurrent atrial flutter; Pulsed field ablation; Non-thermal catheter ablation; Catheter ablation; Electrophysiology study

Outcome Measures

Primary Outcomes (2)

• Incidence of primary adverse events within 7 days of the index ablation procedure

  Proportion of subjects experiencing one or more predefined primary adverse events (PAEs) related to the procedure and/or investigational dual-energy ablation system within 7 days after the index ablation procedure. PAEs include major complications such as cardiac tamponade, stroke or transient ischemic attack, major vascular complications, atrioesophageal injury, pulmonary vein stenosis, and procedure- or device-related death, as defined in the protocol.

  Within 7 days after the index ablation procedure

• Acute procedural success of atypical atrial flutter ablation

  Proportion of subjects in whom acute procedural success is achieved at the end of the index ablation procedure. Acute procedural success is defined as termination and non-inducibility of the clinical atypical atrial flutter and achievement of bidirectional conduction block across the targeted ablation line, confirmed by differential pacing. Cases requiring additional radiofrequency ablation because pulsed-field ablation alone cannot terminate the arrhythmia or achieve bidirectional block will be classified as acute treatment failures.

  At the end of the index ablation procedure

Secondary Outcomes (1)

• Freedom from recurrent atrial arrhythmias

  From the end of the 3-month blanking period through 12 months after the index ablation procedure.

Other Outcomes (11)

• Durability of pulsed-field linear lesions on repeat electroanatomic mapping

  Approximately 3 months (± 4 weeks) after the index ablation procedure.

• Change in left atrial scar burden on cardiac MRI with late gadolinium enhancement

  Baseline, 3 months, and 12 months after the index ablation procedure.

• Serial changes in serum cardiac troponin I/T levels

  Baseline, within 24 hours after the index ablation procedure, and at 3, 6, 9, and 12 months after the index ablation procedure.

Study Arms (1)

Point-by-Point Pulsed-Field Ablation (PFA)

EXPERIMENTAL

All participants in this experimental arm will undergo catheter ablation for recurrent atypical atrial flutter using a point-by-point pulsed-field ablation strategy with the Biosense Webster Dual Energy system (TRUPULSE™ generator and Dual Energy THERMOCOOL SMARTTOUCH™ SF catheter) guided by CARTO™ 3 electroanatomic mapping. Linear or focal lesions will be created along the critical isthmus or scar-related circuit to achieve termination of atypical flutter and bidirectional conduction block. If bidirectional block cannot be achieved with pulsed-field ablation alone, radiofrequency energy using the same system may be applied as a bail-out at the operator's discretion.

Procedure: Point-by-point pulsed-field catheter ablation

Interventions

Point-by-point pulsed-field catheter ablation PROCEDURE

Point-by-point pulsed-field catheter ablation delivered with a dual-energy pulsed field/radiofrequency ablation system. The procedure is guided by 3D electroanatomic mapping to identify the critical isthmus or scar-related circuit responsible for recurrent atypical atrial flutter. Linear or focal lesions are created with point-by-point pulsed-field applications along the targeted line to achieve arrhythmia termination and durable bidirectional conduction block. Radiofrequency energy using the same catheter and generator may be applied only as a bail-out strategy if pulsed-field ablation alone fails to achieve the acute endpoint.

Point-by-Point Pulsed-Field Ablation (PFA)

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients with clinically documented recurrent atypical AFL (based on ECG findings or electrophysiological study findings) after previous ablation for pulmonary vein isolation or atypical AFL within 5 years. The use of oral anticoagulation will follow current guidelines before and after the ablation procedure. In brief, oral anticoagulation will be administered for at least 4 weeks before the procedure.
• Patients undergoing elective AFL ablation using point-by-point PFA (BWI PFA/RFA ablation system), for any of the following types of atypical AFL: gap reentrant, perimetral, roof-dependent, bi-atrial, or scar-related atypical AFL.
• Patients aged ≥18 and \<80.
• Patient is willing and capable of providing informed consent.
• Patient is willing and capable of participating in all follow-up assessments and testing associated with this clinical investigation at an approved clinical investigation center.

You may not qualify if:

• those with AFL due to reversible conditions (e.g., thyroid disorders, acute alcohol intoxication, or recent major surgeries),
• those who had acute coronary syndrome, underwent percutaneous coronary intervention, or had valve or coronary bypass grafting surgery in the 90 days preceding the procedure, or receiving surgical interventions with mechanical valve implants, and
• those with documented cardiac thrombus before the procedure, a history of cardiac thrombus, stroke, or transient ischemic attack in the previous 90 days.
• Categorized as vulnerable population and requires special treatment with respect to safeguards of well being.
• Any of the following atrial conditions:
• Left atrial anteroposterior diameter ≥ 5.5 cm, or if LA diameter not available, non-indexed volume \>100 ml (physician note or imaging)
• Current atrial myxoma
• Any PV abnormality, stenosis, or stenting (common and middle PVs are admissible)
• Any of the following CV conditions:
• History of sustained ventricular tachycardia or any ventricular fibrillation
• Current or anticipated pacemaker, implantable cardioverter defibrillator or cardiac resynchronization therapy devices, or implantable loop recorder.
• Prior interatrial baffle, atrial septal patch, atrial septal defect closure device, patent foramen ovale occluder, Amulet devices, or other left atrial appendage closure device if implanted within 90 days of enrollment
• Presence of any of the following:
• Moderate to severe mitral valve stenosis
• More than moderate mitral regurgitation (\>3+)；

Sponsors & Collaborators

• Taipei Veterans General Hospital, Taiwan: lead
• Biosense Webster, Inc.: collaborator

Study Sites (1)

Taipei Veterans General Hospital

Taipei, 112, Taiwan

Location

MeSH Terms

Conditions

Atrial Flutter

Condition Hierarchy (Ancestors)

Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Masking Details: This is an open-label, single-arm study. All participants and investigators are aware of the treatment assignment, and no masking or blinding procedures are implemented.
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER GOV
• Responsible Party: SPONSOR

Model Details: Single-center, prospective, non-randomized, single-arm study in which all enrolled subjects undergo catheter ablation with point-by-point pulsed-field ablation using the Biosense Webster Dual Energy system, with standardized electroanatomic mapping and protocol-driven follow-up including repeat electrophysiology study and imaging.

Study Record Dates

• First Submitted: December 23, 2025
• First Posted: January 23, 2026
• Study Start: January 9, 2026
• Primary Completion (Estimated): December 31, 2028
• Study Completion (Estimated): December 31, 2028
• Last Updated: February 17, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

TW (1)