A New Approach to Target the Substrates of Persistent Atrial Fibrillation: The Sequential Substrate Ablation Approach

Study Overview
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Brief Summary
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This is a prospective randomized controlled trial that compares the conventional stepwise approach with a new sequential substrate ablation approach for persistent atrial fibrillation.

Detailed Description
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A total number of 100 patients with persistent AF were randomized to receive either conventional stepwise ablation (conventional group) or a sequential substrate ablation (substrate group), both with the endpoint of AF termination. All patients were in AF before the procedure. The sequential substrate ablation consisted of pulmonary vein isolation (PVI) followed by cardioversion and linear ablation at the mitral isthmus, left atrial roof and cavotricuspid isthmus in order to modify the AF substrate. After achievement of bidirectional block, AF was re-induced and electrogram-based ablation was performed to achieve AF termination to sinus rhythm (SR). Endpoints are single-procedure outcome and total amount of RF ablation time required to terminate AF by electrogram-guided ablation.

Official Title
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A New Approach to Target the Substrates of Persistent Atrial Fibrillation: The Sequential Substrate Ablation Approach

Conditions
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Persistent Atrial Fibrillation

Intervention / Treatment
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* Procedure: Ablation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: persistent atrial fibrillation lasting longer than 3 months no previous ablations at least 1 electrical cardioversion Exclusion Criteria: non-persistent atrial fibrillation previous ablation procedures
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

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
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Group A: stepwise ablation<br>Stepwise ablation of persistent atrial fibrillation (conventional treatment arm) In this arm, patients will be treated with the conventional stepwiese ablation approach | Procedure: Ablation<br>* In both arms, patients will undergo an ablation procedure for persistent atrial fibrillation. The sequence of ablation steps are different between both arms.<br>|
| Active Comparator: Group B: sequential substrate ablation<br>Sequential substrate ablation of persistent atrial fibrillation (novel procedure) In this arm, patients will undergo an ablation procedure that consist of PVI, cardioversion, linear ablation and atrial fibrillation re-induction after blocked lines, followed by electrogram-guided ablation | Procedure: Ablation<br>* In both arms, patients will undergo an ablation procedure for persistent atrial fibrillation. The sequence of ablation steps are different between both arms.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of patients without any arrhythmias during follow-up of 12 months |  | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Persistent atrial fibrillation, catheter ablation, outcome