Driver-guided Ablation of Persistent Atrial Fibrillatiom

Study Overview
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Brief Summary
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This is a prospective, single-center, study. A targeted number of 181patients with persistent AF will be included according to pre-defined criteria. The ablation procedure consists on the identification of the arrhythmic substrate using a novel integrated mapping technique. We hypothesize that such approach may potentially lead to a mechanisms-targeted ablation strategy of persistent AF.

Detailed Description
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This is a prospective, single-center, study enrolling a total of 181patients with persistent AF according to well defined inclusion and exclusion criteria. The ablation procedure consists on the identification of the arrhythmic substrate using a novel integrated 3D mapping technique followed by standard CPVA at the end of the procedure. We will ablate substrates showing fast and regular electrical activities, starting from areas with the fastest mean cycle length and/or areas that have consistent rotational or focal propagation pattern and/or areas that comprise the slow conduction zone of possible arrhythmia circuits. After substrate ablation and AF termination, arrhythmia inducibility will be assessed and, if not inducible, the procedure will be completed by standard CPVA. If AF is still inducible, a new 3D map will be performed to identify further targets to be eliminated. Electrical cardioversion may be done at the end of the procedure. We hypothesized that such approach may potentially lead to a mechanisms-targeted ablation strategy leading to elimination of arrhythmic sources in individual patients, thus improving their clinical outcome. We will also characterize, identify and target the real pathophysiological substrates. After ablation, AF recurrence will be assessed by implantable loop recorder or thans-telephonic ECG recording from the end of the 3 months blanking period to 12 months following the procedure.The duration of this study is expected to be 24 months, from the first patient enrollment to the last patient follow-up.

Official Title
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Driver-guided Ablation in the Treatment of Persistent Atrial Fibrillation

Conditions
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Persistent Atrial Fibrillation

Intervention / Treatment
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* Procedure: Catheter ablation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age (18-85 years), persistent AF according to ESC/EHRA guidelines, first or second ablation procedure, ability to provide informed written consent. - Exclusion Criteria: Secondary AF, Hyperthyroidism, LVEF<30%, NYHA functional class IV, uncorrected valvular heart diseases, contraindication to anticoagulation, left atrial thrombus, recent (<6 months) myocardial infarction, thoracic surgery for congenital, valvular diseases, History of cerebrovascular events, pregnancy, cancer or other significant comorbidities. -

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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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Procedure: Catheter ablation|Driver-guided catheter ablation of persistent atrial fibrillation|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Freedom from any AF or atrial tachycardia assessed from the end of the months blanking period to 12 months after ablation. | AF recurrences will be documented by implantable loop recorder or trns-telephonic ECG recording | 12 months after ablation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Identification of electrophysiological substrate | Areas with fast but regular activities or with consistent wave front propagation pattern, or with low P-P voltage, or complex fractionated electrograms | during the procedure | 
| inducibility of AF after the procedure | programmed atrial stimulation before and after isoproterenol | during the procedure | 
| AF burden | Assessment of AF burden by trans-telephonic ECG recording or implantable loop recorder | 12 months after ablation |