Invasive and Clinical Features in Patients With Brugada Syndrome Undergoing Catheter Ablation

Study Overview
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Brief Summary
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This clinical trial aims to learn about the electrophysiological and clinical effects of radiofrequency catheter ablation in patients with Brugada syndrome. The main questions it seeks to answer are: What are the immediate effects of catheter radiofrequency ablation in cardiac electrophysiology? What is the relation between invasive and clinical features in patients with Brugada syndrome undergoing ablation? Researchers will compare ablation and control groups to see if there is a difference in clinical and invasive markers of the disease in one year of follow-up.

Detailed Description
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Brugada syndrome (BS) is an electric cardiac disorder characterized by a typical electrocardiographic pattern and an increased risk of cardiac arrhythmias and sudden death. Most arrhythmic events occur during rest, fever or under circumstances of increased vagal activity. In the last decade, catheter ablation has emerged as a valuable and potentially curative therapy for patients with BS. However, little is known about its mechanisms or long-term effects on clinical and invasive markers. This prospective, single-centre, randomized, sham-controlled, and masked pilot study will investigate the impact of catheter ablation in 20 patients with Brugada syndrome, who will be randomized to ablation or control group, with a 1:1 allocation ratio and clinically followed for 12 months.

Official Title
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Invasive and Clinical Features in Patients With Brugada Syndrome Undergoing Catheter Ablation: a Prospective, Single-centre, Randomized, Sham-controlled, and Masked Pilot Study

Conditions
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Brugada Syndrome

Intervention / Treatment
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* Device: Radiofrequency catheter ablation
* Device: Sham procedure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with a type 1 Brugada ECG pattern, as characterized by ST-segment elevation (≥2mm) with upward concavity associated with T-wave inversion, in at least one of the right precordial leads, positioned at the second, third or fourth intercostal space, either spontaneously or induced by a provocative test with Class I anti-arrhythmic drugs according to Vaughan Williams Patients clinically stable for at least six months before the enrollment Able to cope with follow-up visits up to one year after the intervention Patients who have signed the written informed consent Exclusion Criteria: Pregnant women Patients with structural heart disease Patients with a known cardiac or systemic autonomic disorder Patients with a history of previous right ventricular outflow tract ablation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Prospective, single-centre, randomized, sham-controlled, and masked pilot study with two parallel arms, with a 1:1 allocation ratio to ablation or control group.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Ablation<br>Radiofrequency catheter ablation of the abnormal - prolonged and fragmented - electrophysiologic substrate of Brugada syndrome | Device: Radiofrequency catheter ablation<br>* Radiofrequency application via catheter to burn the electroanatomic substrate implicated in Brugada syndrome<br>|
| Sham Comparator: Control<br>Femoral venous punctions, catheter insertion, programmed electrical stimulation and electroanatomic mapping, with a similar duration to the ablation procedure | Device: Sham procedure<br>* Venous and epicardial punctions, catheter insertions, programmed electrical stimulation and electroanatomical mapping<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Area of abnormal potentials | Electroanatomic duration map | first 30 minutes after the intervention | 
| Induction of sustained ventricular arrhythmias by programmed electrical stimulation | Programmed electrical stimulation (PES) performed on two sites (right ventricular apex and right ventricular outflow tract, unless the patient had inducible ventricular tachycardia at the first location), with energy of twice the diastolic threshold, using two drive cycles (S1: 600 and 430 ms) up to 3 extra stimuli (S2 to S4) with 200 ms as the shortest coupling time. The PVS result is considered positive if sustained ventricular fibrillation or polymorphic ventricular tachycardia is induced. | first 30 minutes after the intervention | 
| Maximum potential duration | Maximum length of ventricular signs on bipolar electrogram | first 30 minutes after the intervention | 
| Local activation time | Measured by unipolar catheters placed in the epicardial and endocardial ventricular surfaces | first 30 minutes after the intervention | 
| Activation recovery interval | Surrogate marker of the action potential duration, measured by unipolar catheters placed in the epicardial and endocardial ventricular surfaces | first 30 minutes after the intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Spontaneous type 1 Brugada electrocardiographic pattern in standard12 lead and superior leads electrocardiogram | Upward ST segment elevation ST-segment elevation ≥2 mm followed by a negative T wave (type 1 Brugada electrocardiographic pattern) in one or more right precordial leads V1 and/or V2 positioned in the second, third, or fourth intercostal spaces. | up to one year after the procedure | 
| Spontaneous type 1 Brugada electrocardiographic pattern in 12 lead 24 hour Holter monitoring | Upward ST segment elevation ST-segment elevation ≥2 mm followed by a negative T wave (type 1 Brugada electrocardiographic pattern) in one or more right precordial leads V1 and/or V2 positioned in the second, third, or fourth intercostal spaces during 12 lead 24h Holter ECG Monitoring | up to one year after the procedure | 
| Spontaneous type 1 Brugada electrocardiographic pattern during treadmill test | Upward ST segment elevation ST-segment elevation ≥2 mm followed by a negative T wave (type 1 Brugada electrocardiographic pattern) in one or more right precordial leads V1 and/or V2 positioned in the second, third, or fourth intercostal spaces, during treadmill test. | up to one year after the procedure | 
| Occurrence of life threatening arrhythmic events | Occurrence of at least one of the following: arrhythmic syncope, documented sustained ventricular tachycardia or ventricular fibrillation, sudden cardiac death or appropriate implantable cardiac defibrillator therapy | up to one year after the procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Brugada syndrome, Radiofrequency catheter ablation, Electroanatomic mapping, Invasive electrophysiological study