Atrial Fibrillation Stratification Based on the Arrhythmia Perpetuation Mechanisms

Study Overview
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Brief Summary
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Atrial fibrillation treatments have a limited efficacy and often cause long-term side effects. This study aims to develop and validate an ECGI system to risk stratification in patients with persistent AF, identifying the mechanisms responsible for the maintenance and the best treatment for ending it.

Detailed Description
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The MAIN GOAL of this project is to clinically validate the technology for the noninvasive identification of the mechanisms responsible for maintenance of AF using ECGI. To achieve this goal, the investigators will analyze the efficacy of different treatment options in persistent AF patients as a function of the results of the ECGI. Mainly, patients will be evaluated attending to the complexity of the patterns obtained. Moreover, the investigators will evaluate the treatment benefit of performing guided-ablation in conjunction with pulmonary vein isolation as compared to pulmonary vein isolation only. These analyses will be performed in patients with persistent AF arriving at the clinic to determine treatment options. AF outcomes following the treatment assigned therapy will be evaluated at 6 months and 1 year after. These parameters are obtained from the ECGI map: histogram of rotors (number of rotors and location), Highest and Lowest Dominant Frequency (Hz), rotor duration (ms), simultaneous rotors (number of rotors) and signal entropy (normalized). Wide antrum circumferential pulmonary vein isolation with demonstration of bidirectional block will be performed using standard cooled-tip radiofrequency catheters or cryoballoon catheters.

Official Title
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STRATIFY TRIAL: Atrial Fibrillation Stratification Based on the Arrhythmia Perpetuation Mechanisms.

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Other: diagnostic strategy using ECGI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with paroxysmal AF symptomatic and refractory to at least one antiarrhythmic medication arriving in atrial fibrillation to the AF clinic. Patients with paroxysmal AF undergoing AF ablation in whom AF was induced at the EP laboratory. Patients with persistent AF or long-term persistent AF attending the AF clinic. Patients must be able and willing to provide written informed consent to participate in the study. Prior anticoagulation for> 4 weeks or transesophageal echocardiogram excluding intracardiac thrombi. Exclusion Criteria: Inclusion Criteria: Patients with paroxysmal AF symptomatic and refractory to at least one antiarrhythmic medication arriving in atrial fibrillation to the AF clinic. Patients with paroxysmal AF undergoing AF ablation in whom AF was induced at the EP laboratory. Patients with persistent AF or long-term persistent AF attending the AF clinic. Patients must be able and willing to provide written informed consent to participate in the study. Prior anticoagulation for> 4 weeks or transesophageal echocardiogram excluding intracardiac thrombi. Exclusion Criteria: Patients with inadequate anticoagulation levels, left atrial thrombus, tumor, or another abnormality which precludes catheter introduction on TEE prior to the procedure. Patients with moderate-to-severe mitral regurgitation. Patients with contraindications to systemic anticoagulation with heparin or coumadin. Patients who are or may potentially be pregnant. Current enrollment in another investigational drug or device study. Pacemaker or Implantable Cardioverter Defibrillator.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 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 |
| --- |
|Other: diagnostic strategy using ECGI|Procedure: Drug treatment, CVE, Pulmonary vein ablation isolation according to treatment guidelines and investigators discretion. ECGI: customized body surface mapping (57 electrodes) at the inclusion in the study, after treatment assignment and prior to AF ablation procedure.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ECGI calculation of frecuency maps(Hz) | Freedom from atrial fibrillation treated according to the ESC/AHA Atrial Fibrillation Guidelines in relation to the ECGI AF complexity score | 12 months post-first intervention | 
| ECGI calculation of frecuency of rotor maps | number of rotors mesasured Atrial Fibrillation Guidelines in relation to the ECGI AF complexity score | 12 months post-first intervention | 
| ECGI AF complexity score calculated from the results of 1 and 2 to evaluate AF freedom from atrial fibrilation | score calculated from the results of 1 and 2 to evaluate AF freedom from atrial fibrilation Atrial Fibrillation Guidelines in relation to the ECGI AF complexity score | 12 months post-first intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Freedom from atrial fibrillation treated according to the ESC/AHA atrial fibrillation Guidelines evaluated in binary(0:AF Freedom;1:AF) |  | 12 months post-first intervention | 
| Freedom from atrial fibrillation in patients undergoing rhythm control drug treatment. |  | at 6 and 12 months | 
| Freedom from atrial fibrillation and other atrial arrhythmias in patients undergoing surgical AF ablation. |  | at 6 and 12 months | 
| ECGI calculations of Highest Dominant Frecuency(Hz) |  | during ablation procedure and 12 months after | 
| ECGI calculations of Lowest Dominant Frecuency(Hz) |  | during ablation procedure and 12 months after | 
| ECGI calculations of Rotor duration from rotor maps(ms) |  | during ablation procedure and 12 months after | 
| ECGI calculations of simultaneus number of rotors from rotor maps(ms) |  | during ablation procedure and 12 months after | 
| Ablation procedure duration |  | Duration of ablation procedure | 
| Electrophysiological characteristics of the Atrial fibrillation complexity | Atrial fibrillation characteristics will be assesed according to the parameters obtained from ECGi calculations. These parameters are obtained from the frecuency maps(Hz) and histogram of rotors(number of rotors and location) and include : Highest and Lowest Dominant Frecuency(Hz), rotor duration(ms) and simultaneous rotors(number of rotors) | Inclusion, rhythm vs rate treatment, ablation | 
| Electroanatomic reconstruction and recordings of electrical activity | a three-dimensional reconstruction of atrium and coronary sinus is obtained using high density catheters and an electroanatomic navigation system. | During ablation procedure | 
| Fluoroscopy time |  | During ablation procedure, in minutes | 
| Trained Neural Network based on ECGI signals |  | 6 and 12 month post-ablation outcome prediction |