Distinct Substrates of Idiopathic Ventricular Fibrillation Revealed by Arrhythmia Characteristics on Implantable Cardioverter-Defibrillator.

Background: Idiopathic ventricular fibrillation (IVF) can be associated with undetected distinct conditions such as microstructural cardiomyopathic alterations (MiCM) or Purkinje (Purk) activities with structurally normal hearts.

Objectives: This study sought to evaluate the characteristics of recurrent VF recorded on implantable defibrillator electrograms, associated with these substrates.

Methods: This was a multicenter collaboration study.

Brugada syndrome in Japan and Europe: a genome-wide association study reveals shared genetic architecture and new risk loci.

Background And Aims: Brugada syndrome (BrS) is an inherited arrhythmia with a higher disease prevalence and more lethal arrhythmic events in Asians than in Europeans. Genome-wide association studies (GWAS) have revealed its polygenic architecture mainly in European populations. The aim of this study was to identify novel BrS-associated loci and to compare allelic effects across ancestries.

Clinical Management of Brugada Syndrome: Commentary From the Experts.

Although there is consensus on the management of patients with Brugada Syndrome with high risk for sudden cardiac arrest, asymptomatic or intermediate-risk patients present clinical management challenges. This document explores the management opinions of experts throughout the world for patients with Brugada Syndrome who do not fit guideline recommendations. Four real-world clinical scenarios were presented with commentary from small expert groups for each case.

Sex differences in clinical characteristics, management, and outcomes in patients admitted for ventricular tachycardia: 2016-2018.

Introduction: The concurrent data on sex disparities in VT management and outcomes have remained unclear. Therefore, our objective was to determine the impact of sex on ventricular tachycardia (VT) management and outcomes in patients admitted with VT, dervied from the US National Inpatient Sample database (NIS).

Methods: We used data from the US NIS to identify hospitalized adult patients who were admitted with VT between 2016 and 2018.

A diverse ancestrally-matched reference panel increases genotype imputation accuracy in a underrepresented population.

Variant imputation, a common practice in genome-wide association studies, relies on reference panels to infer unobserved genotypes. Multiple public reference panels are currently available with variations in size, sequencing depth, and represented populations. Currently, limited data exist regarding the performance of public reference panels when used in an imputation of populations underrepresented in the reference panel.

Long-Term Outcomes of Brugada Substrate Ablation: A Report from BRAVO (Brugada Ablation of VF Substrate Ongoing Multicenter Registry).

Background: Treatment options for high-risk Brugada syndrome (BrS) with recurrent ventricular fibrillation (VF) are limited. Catheter ablation is increasingly performed but a large study with long-term outcome data is lacking. We report the results of the multicenter, international BRAVO (Brugada Ablation of VF Substrate Ongoing Registry) for treatment of high-risk symptomatic BrS.

Metagenomic analysis of viral genes integrated in whole genome sequencing data of Thai patients with Brugada syndrome.

Brugada syndrome (BS) is an autosomal dominant inheritance cardiac arrhythmia disorder associated with sudden death in young adults. Thailand has the highest prevalence of BS worldwide, and over 60% of patients with BS still have unclear disease etiology. Here, we performeda new viral metagenome analysis pipeline called VIRIN and validated it with whole genome sequencing (WGS) data of HeLa cell lines and hepatocellular carcinoma.

Brugada syndrome in Thailand: Three decades of progress.

Our group began investigating the cause of sudden unexplained death syndrome in Thailand in 1994 and found that among sudden unexplained death syndrome patients, the Brugada phenotype was ubiquitous. Following this important observation, Brugada syndrome (BrS) became our main research focus and has galvanized our collaboration with several global prominent scientists over the past 30 years. Through this collaborative research, we made major progress toward better understanding of the syndrome and gained knowledge in genetic background, pathophysiology, and new management.

Advances in Ventricular Arrhythmia Ablation for Brugada Syndrome.

Three decades have passed since the Brugada syndrome (BrS) clinical entity was introduced in the early 1990s. During the first 2 decades, treatment of patients with BrS was challenging because there were limited treatment options, and an implantable cardioverter-defibrillator was the only choice for high-risk patients with BrS, that is, those who had aborted sudden cardiac death or had previous ventricular fibrillation episodes. In this article, the authors focus on these advances and how to treat patients with BrS with catheter ablation.

Mechanism of the effects of sodium channel blockade on the arrhythmogenic substrate of Brugada syndrome.

Background: The mechanisms by which sodium channel blockade and high-rate pacing modify electrogram (EGM) substrates of Brugada syndrome (BrS) have not been elucidated.

Objective: The purpose of this study was to determine the effect of ajmaline and high pacing rate on the BrS substrates.

Methods: Thirty-two patients with BrS (mean age 40 ± 12 years) and frequent ventricular fibrillation episodes underwent right ventricular outflow tract substrate electroanatomical and electrocardiographic imaging (ECGI) mapping before and after ajmaline administration and during high-rate atrial pacing.

2020 APHRS/HRS expert consensus statement on the investigation of decedents with sudden unexplained death and patients with sudden cardiac arrest, and of their families.

This international multidisciplinary document intends to provide clinicians with evidence-based practical patient-centered recommendations for evaluating patients and decedents with (aborted) sudden cardiac arrest and their families. The document includes a framework for the investigation of the family allowing steps to be taken, should an inherited condition be found, to minimize further events in affected relatives. Integral to the process is counseling of the patients and families, not only because of the emotionally charged subject, but because finding (or not finding) the cause of the arrest may influence management of family members.

Role of Catheter Ablation for Ventricular Arrhythmias in Brugada Syndrome.

Purpose Of Review: To discuss the role of catheter ablation in treating life-threatening ventricular arrhythmias associated with Brugada syndrome (BrS), by presenting recent findings of BrS arrhythmogenic substrate, mechanisms underlying ventricular arrhythmias, and how they can be treated with catheter ablation.

Recent Findings: Almost three decades ago when the clinical entity of Brugada syndrome (BrS) was described in patients who had abnormal coved-type ST elevation in the right precordial EKG leads in patients who had no apparent structural heart disease but died suddenly from ventricular fibrillation. Since its description, the syndrome has galvanized explosive research in this field over the past decades, driving major progress toward better understanding of BrS, gaining knowledge of the genetic pathophysiology and risk stratification of BrS, and creating significant advances in therapeutic modalities.

Phenotype prediction and characterization of 25 pharmacogenes in Thais from whole genome sequencing for clinical implementation.

Publicly available pharmacogenomics (PGx) databases enable translation of genotype data into clinically actionable information. As variation within pharmacogenes is population-specific, this study investigated the spectrum of 25 clinically relevant pharmacogenes in the Thai population (n = 291) from whole genome sequencing. The bioinformatics tool Stargazer was used for phenotype prediction, through assignment of alleles and detection of structural variation.

2020 APHRS/HRS expert consensus statement on the investigation of decedents with sudden unexplained death and patients with sudden cardiac arrest, and of their families.

This international multidisciplinary document intends to provide clinicians with evidence-based practical patient-centered recommendations for evaluating patients and decedents with (aborted) sudden cardiac arrest and their families. The document includes a framework for the investigation of the family allowing steps to be taken, should an inherited condition be found, to minimize further events in affected relatives. Integral to the process is counseling of the patients and families, not only because of the emotionally charged subject, but because finding (or not finding) the cause of the arrest may influence management of family members.

Mapping and Ablation of Ventricular Fibrillation Associated With Early Repolarization Syndrome.

Background: We conducted a multicenter study to evaluate mapping and ablation of ventricular fibrillation (VF) substrates or VF triggers in early repolarization syndromes (ERS) or J-wave syndrome (JWS).

Methods: We studied 52 patients with ERS (4 women; median age, 35 years) with recurrent VF episodes. Body surface electrocardiographic imaging and endocardial and epicardial electroanatomical mapping of both ventricles were performed during sinus rhythm and VF for localization of triggers, substrates, and drivers.