An interventional study of Pulse field ablation and Radiofrequency ablation in Persistent Atrial Fibrillation and Longstanding Persistent Atrial Fibrillation, sponsored by University Medical Centre Ljubljana. Active, not recruiting at 1 site in Slovenia. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-02-11.
Sponsored by University Medical Centre Ljubljana · Not applicable, Interventional, and Treatment
Comparison of pulmonary vein and left atrial posterior wall isolation durability and clinical outcome between radiofrequency and pulse field ablation in patients with persistent and longstanding persistent atrial fibrillation.
Patients with persistent and longstanding persistent atrial fibrillation will be randomized to control and investigational group.
In control group they will receive pulmonary vein and posterior wall ("box lesion") isolation with point by point radiofrequency ablation utilizing the CLOSE protocol with predetermined interlesion distance of up to 6 mm and predetermined ablation index/lesion size index.
In investigational group they will receive pulmonary vein and posterior wall ("box lesion" and additional ablations inside the "box") isolation with point by point pulse field ablation with a predetermined interlesion distance of up to 6 mm and predetermined energy delivery settings.
30 minutes after the last ablation point a high-density mapping of the left atrium will be performed.
Preprocedurally all patients will undergo computer tomography angiography of the left atrium, which will be processed resulting in a three dimensional anatomy reconstruction that will be utilized during the procedures in conjunction with the three dimensional mapping system. Also, left atrial wall thickness will be determined and displayed on the three dimensional anatomy reconstruction.
Before and after radiofrequency and pulse field ablation a five minute bipolar and unipolar intracardiac electrogram recording will be performed at at least two predetermined locations according to wall thickness (at the thinest and at the thickest part of the wall) for later analysis of changes due to different modes of ablation with correlation to lesion durability at a three month re-mapping procedure.
Collection of full blood before and 24 and 48 hours after the procedure to analyse activation of inflammation, coagulation, and also nevral tissue injury and endotelial injury due to ablation. Deviation of markers from the baseline value before the procedure will serve as a measure of activation. Markers analysed: troponin (ng/ml), D dimer (mg/l fibrinogen equivalent units), protein S100 (ng/ml), protein NSE (ng/ml), NT proBNP (pg/ml), high sensitivity CRP (mg/l), interleukin (IL) 6 (pg/ml), procalcitonin (ng/ml), fibrinogen (g/l), P selectin /pg/ml).
Postprocedurally pateints will undergo a remapping procedure three months later to determine pulmonary vein and left atrial posterior wall isolation durability.
Pateints will be followed up with clinical checkup and 1-7 day ECG holters at 3, 6, 12 months.
3,870 studies on the registry are indexed under Atrial Fibrillation; 924 are open to participants now.
This study's planned enrollment of 50 is below the median of 144 across 2,380 interventional studies indexed under Atrial Fibrillation.
Browse Atrial Fibrillation studies →University Medical Centre Ljubljana is the lead sponsor of 284 studies on the registry; 71 are open to participants now.
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Exclusion Criteria:
Pulmonary vein and left atrial posterior wall isolation with point by point radiofrequency ablation.
Other: Radiofrequency ablation
Pulmonary vein and left atrial posterior wall isolation with point by point pulse field ablation.
Other: Pulse field ablation
Point by point isolation of pulmonary veins and left atrial posterior wall
Point by point isolation of pulmonary veins and left atrial posterior wall
Durability of isolation
Testing for durability of pulmonary vein and left atrial posterior wall isolation in both study arms with high density endocardial remapping. Absence of electrical activity or voltage inside ablation lines of less than 0.05 mV or presence of exit block upon pacing with local capture will be considered as proof of pulmonary vein and posterior left atrial wall isolation.
Time frame: 3 months
Freedom from atrial arrhythmias
Freedom from atrial tachycardia, atrial flutter and atrial fibrillation during the follow up as assessed with 12-lead ECG and 1-7 day holter ECG recordings at 3, 6, 12 months. With holter recordings any arrhythmia lasting at least 30 seconds will be considered as a recurrence.
Time frame: 12 months
Intracardiac electrograms analysis
Five minute recording of bipolar and unipolar intracardiac electrograms with a high density mapping catheter at predetermined locations in pulmonary vein antra and left atrial posterior wall before and after radiofrequency and pulse field ablation at the index procedure. Offline analysis of recorded signals and correlation of immediate changes with persistence of durable lesions (isolation) or conduction gaps.
Time frame: 1 day
Recording of complications
Postprocedural endoscopy of the esophagus and endoscopic ultrasound of the esophagus up to 72 hours after the procedure for detection of esophageal injury. Recording of any intra and postprocedural complications up to a 30 day period.
Time frame: 30 days
Plan to share: No
No publications or documents are linked to this record.
This study is active, not recruiting, as verified in Feb 2026. You cannot join it, but the record below documents what was studied.
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University Medical Centre Ljubljana