Adjunctive Ganglionated Plexus Ablation in Redo-Pulmonary Vein Isolation

Study Overview
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Brief Summary
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The investigator propose to test the efficacy of adjunctive ET-GP ablation in patients undergoing redo PVI for paroxysmal AF.

Detailed Description
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Patients with ongoing paroxysmal arrhythmias after pulmonary vein isolation (PVI) for paroxysmal and persistent atrial fibrillation (AF) get incrementally less benefit with redo-PVI. This implies non-pulmonary vein (PV) triggers, which are more challenging to locate. The autonomic nervous system is implicated in the multifactorial pathogenesis of AF but few studies have attempted neural targeting as a therapeutic intervention. We have demonstrated that stimulation of specific left atrial ganglionated plexi (GPs) triggers both AF and atrial ectopy and importantly stimulation of these sites may not induce AV block, the 'conventional' marker used to locate GPs. Having shown that these ectopy-triggering GP (ET-GP) sites are anatomically stable and can be rendered inactive by either ablation at the site or by ablation between the site and the adjacent PV, a single centre study suggests that ET-GP ablation can prevent recurrent AF in some patients.

Official Title
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Adjunctive GP Ablation In Redo-PVI: Paroxysmal Atrial Arrhythmias After Pulmonary Vein Isolation Are Driven By Ectopy-Triggering Left Atrial Ganglionated Plexus

Conditions
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Atrial Fibrillation, Paroxysmal Atrial Fibrillation

Intervention / Treatment
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* Procedure: Radiofrequency ablation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Males or females eighteen (18) to eighty five (85) years old Paroxysmal atrial fibrillation Previous pulmonary vein isolation Suitable candidate for catheter ablation Signed informed consent Exclusion Criteria: Contraindication to catheter ablation Presence of a cardiac thrombus Valvular disease that is grade moderate or greater Any form of cardiomyopathy On amiodarone therapy Patients who lack capacity Active gastrointestinal bleeding Active infection or fever Renal failure (Creatinine >200µmol/L) Life expectancy shorter than the duration of the trial Bleeding or clotting disorders or inability to receive heparin Pregnant

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomised, controlled, prospective study
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Redo pulmonary vein isolation<br> | Procedure: Radiofrequency ablation<br>* RF application to achieve complete pulmonary vein isolation +/- ganglionated plexus ablation<br>|
| Active Comparator: Ganglionated plexus ablation + redo pulmonary vein isolation<br> | Procedure: Radiofrequency ablation<br>* RF application to achieve complete pulmonary vein isolation +/- ganglionated plexus ablation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Any atrial arrhythmia >30s documented on ECGs | After blanking period 3 months | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Symptom recurrence requiring repeat ablations |  | 12 months | 
| Complications |  | 12 months | 
| Radiofrequency time |  | Within ablation procedure |