Ablation for the treatment of Brugada syndrome: current status and future prospects

ABSTRACT

Introduction: Brugada syndrome (BrS) is an inherited disease characterized by an increased risk of sudden cardiac death (SCD). Therapeutic options in symptomatic patients are limited to implantable cardioverter defibrillator (ICD) and quinidine, but catheter ablation of the right ventricular outflow tract (RVOT) offers a potential cure. Different ablation strategies have been used to treat patients with symptomatic Brugada syndrome. Epicardial radiofrequency substrate ablation of the RVOT/right ventricle (RV) has emerged as a promising tool for the management of the disease.

Areas covered: The historical management of BrS, endocardial and epicardial ablation techniques, the use of sodium channel blockers (SCB) and complications are summarized here.

Expert opinion: Ventricular fibrillation (VF)-triggering premature ventricular contractions (PVCs) in patients with BrS are unpredictable, spontaneous ones are rarely present to be mapped, making this approach impractical. Furthermore, endocardial mapping for BrS substrates does not seem effective due to the epicardial pathological substrate localization. The size variation of the BrS substrate areas during SCB infusion suggests a dynamic process as arrhythmogenic basis and SCB infusion should guide BrS epicardial ablation of all abnormal potentials areas. If BrS epicardial ablation can truly provide long-term prevention of ventricular arrhythmias it may potentially become an alternative to ICD therapy.

KEYWORDS:

• Brugada syndrome
• sudden cardiac death
• ICD
• catheter radiofrequency ablation
• ventricular fibrillation triggers
• right ventricle outflow tract conduction delay
• epicardial substrate ablation
• sodium channel blockers
• hybrid thoracoscopic ablation

Article highlights

• Brugada syndrome is an inherited disease characterized by an increased risk of sudden cardiac death in the absence of structural heart anomalies.

• The cellular mechanisms underlying Brugada syndrome remain debatable. Two principal hypotheses have been proposed: the repolarization hypothesis and the depolarization hypothesis.

• Quinidine is the only drug that has been proven to be effective. ICD is the only therapeutic option found to be effective in preventing death from VF recurrences and it is recommended in BrS symptomatic patients for the prevention of SCD

• Epicardial radiofrequency substrate ablation over the RVOT/RV has emerged as a promising tool for the management of Brugada syndrome.

• Endocardial substrates mapping and VF-triggering PVCs targeting do not seem effective due to the prevalent epicardial pathological substrate localization in the majority of the patients; BrS substrate is almost exclusively located in the epicardium of the RVOT/RV body and rarely present in the endocardium.

• Drug provocation with a sodium channel blocker increases the area of abnormal conduction, which may improve substrate identification and guide ablation strategies

Declaration of interest

GB Chierchia receives compensation for teaching purposes and proctoring from AF solutions Medtronic and Biotronik. P Brugada receives fees from Biotronik and Medtronic. C de Asmundis receives compensation for teaching purposes and proctoring from AF solutions Medtronic, Abbott, Biotronik, Atricure and research grants on behalf of the center from Biotronik, Medtronic, St. Jude Medical Abbott, Livanova, Boston Scientific Biosense Webster. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

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Funding

This paper was not funded.