Identification of Risk Factors for Atrial Fibrillation After Ablation of an Atrial Flutter by Radiofrequency of the Cavotricuspid Isthmus.

Study Overview
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Brief Summary
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Atrial flutter is a common condition that is effectively treated by ablation using radiofrequency. Due to its feasibility, effectiveness and low procedural risk, radiofrequency ablation is a first-line treatment of atrial flutter. Several studies have been published concerning the factors associated with the occurrence of atrial fibrillation during or after flutter ablation, in patients with and without clinical history of atrial fibrillation. 26 to 46% of patients are likely to develop it, according to ECG or Holter diagnoses. The figure rises to more than 50% with a diagnosis with an implantable loop recorder. In patients without a prior history of atrial fibrillation before ablation, anticoagulants are routinely administered 4-6 weeks after flutter removal by most cardiologists. Although there are no specific guidelines for anticoagulation after flutter ablation, it is currently recommended to treat the patient as for atrial fibrillation. It is therefore crucial to identify in advance patients at high risk of atrial fibrillation after flutter ablation, in order to assess the appropriateness of maintaining oral anticoagulant therapy. The objectives of this study are: to evaluate the frequency and identify the factors predicting the occurrence of atrial fibrillation after flutter ablation to determine the risk of a stroke occurring in patients with atrial fibrillation after flutter ablation. The database consists in patients of the CHU Brugmann Hospital treated between 1996 and 2018.

Official Title
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Retrospective Study to Identify Risk Factors for Atrial Fibrillation After Ablation of Atrial Flutter by Radiofrequency of the Cavotricuspid Isthmus.

Conditions
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Flutter

Intervention / Treatment
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* Other: Medical Data extraction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients treated at the CHU Brugmann Hospital for flutter ablation by radiofrequency between 1996 and 2018. Exclusion Criteria: None

Ages Eligible for Study
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Minimum Age: 18 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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Control<br>No atrial arrhythmia post-ablation of a flutter by radiofrequency of the isthmus of the cavotricuspid valva. | Other: Medical Data extraction<br>* Data extraction from the patient's Medical Files<br>|
| Atrial fibrillation post ablation<br>Atrial arrhythmia (Atrial Fibrillation) post-ablation of a flutter by radiofrequency of the isthmus of the cavotricuspid valva. | Other: Medical Data extraction<br>* Data extraction from the patient's Medical Files<br>|
| Flutter recidive<br>Recidive of the flutter after ablation. | Other: Medical Data extraction<br>* Data extraction from the patient's Medical Files<br>|
| Atrial Fibrillation antecedents<br>Patients with atrial fibrillation after flutter ablation, with previous antecedents of atrial fibrillation. | Other: Medical Data extraction<br>* Data extraction from the patient's Medical Files<br>|
| No Atrial Fibrillation antecedents<br>Patients with atrial fibrillation after flutter ablation, without antecedents of atrial fibrillation. | Other: Medical Data extraction<br>* Data extraction from the patient's Medical Files<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Age at ablation | Age of the patient at the date of the flutter ablation | One day | 
| Gender | Gender of the patient at the date of the flutter ablation | One day | 
| Antecedents of ischemic cardiomyopathy | Antecedents of ischemic cardiomyopathy (yes/no) at the date of flutter ablation | One day | 
| Antecedents of cardiomyopathy | Antecedents of cardiomyopathy (yes/no) at the date of flutter ablation | One day | 
| Antecedents of dilated cardiomyopathy | Antecedents of dilated cardiomyopathy (yes/no) at the date of flutter ablation | One day | 
| Diabetes | Diabetes diagnosis (yes/no) at the date of flutter ablation | One day | 
| Chronic pulmonal disease | Chronic pulmonal disease diagnosed at the date of flutter ablation | One day | 
| Cardiac surgery antecedents | Presence of cardiac surgery antecedents at the date of flutter ablation | One day | 
| Atrial fibrillation antecedents | Antecedents of Atrial fibrillation at the date of flutter ablation | One day | 
| Beta-blockers post-ablation | Prescription of Beta-Blockers after the flutter ablation (yes/no) | One day | 
| Amiodarone post-ablation | Prescription of amiodarone after the flutter ablation (yes/no) | One year | 
| Class I antiarrhythmic drugs post-ablation | Prescription of Class I antiarrhythmic drugs post-ablation | One year | 
| Arterial hypertension | Presence of arterial hypertension on the day of flutter ablation | One day | 
| Antecedents of stroke | Antecedents of stroke | One day | 
| Stroke after flutter ablation | Occurence of stroke after the flutter ablation | One year | 
| Antecedents of peripheric thromboembolic events | Antecedents of thromboembolic events on the day of flutter ablation | One day | 
| Peripheric thromboembolic events after flutter ablation | Thromboembolic events after flutter ablation | One year | 
| Atrial Fibrillation apparition delay | Delay of apparition of atrial fibrillation after flutter removal | Up to one year | 
| Left ventricular ejection fraction of the heart | Left ventricular ejection fraction of the heart at the day of flutter removal (echographic data) | One day | 
| Left atrium size of the heart | Left atrium size of the heart at the day of flutter removal (echographic data) | One day | 
| Pulmonary arterial pressure | Pulmonary arterial pressure at the day of flutter removal (echographic data) | One day |