Brugada Syndrome as a Major Cause of Sudden Cardiac Death in Asians

Brugada syndrome (BrS) is one of the main inherited arrhythmia syndromes causing ventricular fibrillation (VF) and sudden cardiac death in young to middle-aged men, especially in Asians. The diagnosis of BrS is based on spontaneous or drug-provoked type 1 Brugada electrocardiogram. The current reliable therapy for BrS patients with VF history is the implantation of an implantable cardioverter-defibrillator. As for BrS patients without VF history, how asymptomatic BrS patients should effectively be treated is still uncertain because risk stratification of the BrS is still inadequate. Various parameters and combinations of several parameters have been reported for risk stratification of BrS. The SCN5A gene is believed to be the only gene that is responsible for BrS, and it has been reported to be useful for risk stratification. This review focuses on risk stratification of BrS patients, and focuses specifically on BrS patients of Asian descent.

ECG in an Athlete With Syncope: Innocuous Incomplete Right Bundle Branch Block or Brugada Pattern?

Abnormalities of an athlete's electrocardiogram may be the result of an underlying heart disease and may carry a risk of sudden death. It is important that electrocardiographic abnormalities are correctly distinguished. We present the case of a young marathon athlete presenting with syncope and incomplete right bundle block pattern suggestive of a type 2 Brugada pattern. (Level of Difficulty: Advanced.).

A Continuous Murmur as the Only Clinical Sign for Complex Coronary Artery Fistulas Diagnosis

An asymptomatic patient presented at our hospital exhibiting a Brugada electrocardiography pattern with coronary artery fistulas. Coronary artery fistula is a congenital or acquired rare abnormal condition with increased symptoms and complications over time. In the absence of the therapeutic consensus, we discuss the association and management for this condition. (Level of Difficulty: Advanced.).

The Brugada Type 1 Electrocardiogram and Ventricular Tachycardia With High-Dose Amitriptyline

A 32-year-old woman with anorexia nervosa experienced ventricular tachycardia while on therapeutic-dose amitriptyline despite normal blood tests, imaging, and intracardiac recordings. Electrocardiograms over several years featured the Type 1 Brugada pattern. Careful electrocardiogram monitoring should be made if using high doses of amitriptyline, especially in those with low body weight. (Level of Difficulty: Intermediate.).

Electrocardiographic "Northwest QRS Axis" in the Brugada Syndrome: A Potential Marker to Predict Poor Outcome

Conduction delay in the right ventricular outflow tract as manifested in the electrocardiogram constitutes a high-risk predictor of ventricular arrhythmias in patients with Brugada syndrome. We present a case with a right QRS axis between –90° and ±180°. This feature has never been reported in the context of Brugada syndrome. (Level of Difficulty: Advanced.)

Out-of-Hospital Cardiac Arrest Due to a Concealed Diagnosis

This case outlines the dynamic and often concealed electrocardiographic findings associated with Brugada syndrome and explores its important relationship with early repolarization syndrome as part of a spectrum of inherited J-wave syndromes. (Level of Difficulty: Beginner.).

Transient, Marked ST-Segment Elevation During Successful Epicardial Substrate Ablation in a Patient With Brugada Syndrome

A 37-year-old man with Brugada syndrome and frequent appropriate implantable cardioverter-defibrillator shocks received an epicardial substrate ablation. During the procedure to eliminate delayed potentials, transient, marked ST-segment elevation in lead V₂ was observed, particularly in the anterior right ventricle with a borderline between normal and low-voltage areas. (Level of Difficulty: Intermediate.).

Recent advances in genetic testing and counseling for inherited arrhythmias

Inherited arrhythmias, such as cardiomyopathies and cardiac ion channelopathies, along with coronary heart disease (CHD) are three most common disorders that predispose adults to sudden cardiac death. In the last three decades, causal genes in inherited arrhythmias have been successfully identified. At the same time, it has become evident that the genetic architectures are more complex than previously known. Recent advancements in DNA sequencing technology (next generation sequencing) have enabled us to study such complex genetic traits.

This article discusses indications for genetic testing of patients with inherited arrhythmias. Further, it describes the benefits and challenges that we face in the era of next generation sequencing. Finally, it briefly discusses genetic counseling, in which a multidisciplinary approach is required due to the increased complexity of the genetic information related to inherited arrhythmias.

Electrocardiographic methods for diagnosis and risk stratification in the Brugada syndrome

The Brugada syndrome (BrS) is a malignant, genetically-determined, arrhythmic syndrome manifesting as syncope or sudden cardiac death (SCD) in individuals with structurally normal hearts. The diagnosis of the BrS is mainly based on the presence of a spontaneous or Na + channel blocker induced characteristic, electrocardiographic (ECG) pattern (type 1 or coved Brugada ECG pattern) typically seen in leads V1 and V2 recorded from the 4th to 2nd intercostal (i.c.) spaces. This pattern needs to be distinguished from similar ECG changes due to other causes (Brugada ECG phenocopies). This review focuses mainly on the ECG-based methods for diagnosis and arrhythmia risk assessment in the BrS. Presently, the main unresolved clinical problem is the identification of those patients at high risk of SCD who need implantable cardioverter-defibrillator (ICD), which is the only therapy with proven efficacy. Current guidelines recommend ICD implantation only in patients with spontaneous type 1 ECG pattern, and either history of aborted cardiac arrest or documented sustained VT (class I), or syncope of arrhythmic origin (class IIa) because they are at high risk of recurrent arrhythmic events (up to 10% or more annually for those with aborted cardiac arrest). The majority of BrS patients are asymptomatic when diagnosed and considered to have low risk (around 0.5% annually) and therefore not indicated for ICD. The majority of SCD victims in the BrS, however, had no symptoms prior to the fatal event and therefore were not protected with an ICD. While some ECG markers such as QRS fragmentation, infero-lateral early repolarisation, and abnormal late potentials on signal-averaged ECG are known to be linked to increased arrhythmic risk, they are not sufficiently sensitive or specific. Potential novel ECG-based strategies for risk stratification are discussed based on computerised methods for depolarisation and repolarisation analysis, a composite approach targeting several major components of ventricular arrhythmogenesis, and the collection of large digital ECG databases in genotyped BrS patients and their relatives.