Combined Study of ATrial Strain and Voltage by High Density Mapping in Young Patients With Atrial Fibrillation.

Study Overview
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Brief Summary
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Atrial The treatment of atrial fibrillation (AF) includes 2 axes: the prevention of the cardio-embolic risk and rhythm control. The possibilities for this control are antiarrhythmic drugs and, above all, catheter ablation, an interventional cardiology technique which consists in treating the areas responsible for the initiation and perpetuation of AF by applying radiofrequency energy or cryotherapy to the myocardial tissue. Limited research has been done on the combination of different parameters to manage AF, especially during the initial stage of the disease. A translational and multimodal approach could make it possible to better characterize this pathology and thus, help to adjust the therapeutic management for the patients. The combined analysis of regional electrophysiological, morphological, and functional parameters of the left atrium could make it possible to better detect early atrial cardiomyopathy and predict recurrences of atrial fibrillation.

Detailed Description
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The electrophysiological substrate for patients with persistent atrial fibrillation is heterogeneous with areas of atrial myocardium of low voltage amplitudes and areas of rapid fragmented signals in arrhythmia. The targets of ablation treatment in these cases are currently poorly defined. Several promising strategies have emerged, such as the isolation of fibrotic areas, low voltage. An integration analysis of regional electrophysiological, morphological, and functional parameters of the left atrium, therefore, open up a new area of research that has not been studied to date and could help to better guide the therapeutic management of patients with AF. The study aims to assess the association between regional and global myocardial strain abnormalities on magnetic resonance imaging (MRI) and the amplitude of the atrial intracardiac electrical potential, in young subjects with symptomatic AF.

Official Title
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Combined Study of ATrial Strain and Voltage by High Density Mapping in Young Patients With Atrial Fibrillation.

Conditions
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Paroxysmal Atrial Fibrillation, Persistent Atrial Fibrillation, Catheter Ablation, Atrial Cardiomyopathy

Intervention / Treatment
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* Diagnostic Test: MRI (with injection of contrast product)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient aged 18 to 60 years Established diagnosis of paroxysmal or persistent symptomatic atrial fibrillation (AF) for at least 3 months with indication of catheter ablation AF episode documented by ECG in the last 12 months Structurally healthy heart, with an LVEF> 50%, an interventricular septum <12 mm and an OG volume <40mL / m ² by TTE Having given their informed consent in writing Affiliated with or entitled to a French social security scheme Exclusion Criteria: Mitral valve disease with grade 2 to 4 insufficiency Heart failure (NYHA stage II to IV in sinus rhythm and LVEF < 50%), hypertrophic heart disease or congenital heart disease Contraindication to oral anticoagulation Intracardiac thrombus History of ablation of the left atrium History of heart surgery Contraindication to performing MRI or using the DOTAREM™ contrast medium (pacemaker, defibrillator, prosthesis, old generation heart valves, old generation ferromagnetic vascular surgical clips, treatment type endocranial aneurysms, neurosimulator, cochlear implants, automated injection device such as insulin pump, and more generally any non-removable electronic medical device or equipment, kidney disease with GFR < 30 mL/min, hypersensitivity to gadoteric acid or to excipients) History of myocardial infarction or coronary angioplasty within the last three months Chronic obstructive pulmonary disease Under guardianship or curatorship Women who are pregnant, breastfeeding or of childbearing age in the absence of effective contraception Participation in another interventional research involving a health product

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 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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Design Details

Primary Purpose: Prevention
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Patients with diagnosed Atrial fibrillation and an indication of catheter ablation<br> | Diagnostic Test: MRI (with injection of contrast product)<br>* All patients included in the study will undergo two MRI examinations (with injection of contrast product) before and after the ablation procedure.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between the regional and global longitudinal strain peaks (percent (%)) and voltage (millivoltage(mV)) of the left atrium measured by MRI and catheter ablation |  | 1 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Localization in the left atrium and area of low amplitude electrogram areas (<0.5 mV, <0.3 mV and <0.1 mV) measured during the ablation procedure |  | 1 month | 
| Localization in the left atrium and areas of fragmented atrial complexes measured during the ablation procedure |  | 1 months | 
| Local atrial impedance measured by ablation catheter |  | 1 months | 
| Contact force measured by ablation catheter |  | 1 month | 
| Local impedance drop measured during radiofrequency delivery |  | 1 month | 
| Duration of the ablation for each radiofrequency delivery |  | 1 month | 
| Localization of the segmental and regional alteration of the myocardium in the left atrium measured during MRI |  | 3 months | 
| Localization of zones with impaired 4D flow in the left atrium measured during MRI |  | 3 months | 
| Left atrium volume (milliliter (mL)) measured during MRI |  | 3 months | 
| Localization of areas of late enhancement in the left atrium |  | 3 months | 
| Lesion transmurality performed by ablation in each segment of the pulmonary veins |  | 3 months | 
| Subcutaneous measurement (AGE Reader) which combines aging and accumulation of glycated proteins in the subcutaneous tissue measured during MRI |  | 3 months | 
| Volumes (milliliter (ml)) of the left atrium: in the basal state and after passive filling measured during echocardiography |  | 1 month | 
| Analysis of the longitudinal deformation (strain) in speckle tracking in the basal state and after passive measured during echocardiography |  | 1 month | 
| Absence of atrial fibrillation occurrence |  | 12 months | 
| Absence of persistent atrial fibrillation occurrence |  | 12 months | 
| Absence of atrial tachycardia or atrial flutter occurrence after catheter ablation |  | 12 months | 
| Absence of palpitation occurrence after catheter ablation |  | 12 months | 
| 6-minute walking test to assess exercise capacity |  | 1 month | 
| Differences in the volumes (milliliter (ml)) of the left atrium (maximum, minimum, atrial pre-systole) between the segmentation performed manually and the segmentation obtained by learning transfer |  | 3 months | 
| Distance between areas of low voltages identified by the cartography and areas of late 3D enhancement identified by MRI, measurement based on the volume (milliliter (ml)) resulting from CT-scan and MRI fusion |  | 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Atrial Fibrillation, Atrial strain, High density electrical mapping, Catheter ablation