Electrocardiographic variables associated with underlying Brugada syndrome or drug-induced Type 1 Brugada pattern in patients with slow/fast atrioventricular nodal reentrant tachycardia.

Background: The coexistence of clinical atrioventricular nodal reentrant tachycardia (AVNRT) and drug-induced type 1 Brugada pattern (DI-Type 1 BrP) has been previously reported. The present study was designed to determine the 12-lead ECG characteristics at baseline and during AVNRT and to identify a subset of 12-lead ECG variables of benefit associated with underlying Brugada syndrome (BrS)/DI-Type 1 BrP among patients with slow/fast AVNRT.

Methods: A total of 40 (11 numerical/29 categorical) 12-lead ECG parameters were analyzed and compared between patients with ( = 69) and without ( = 104) BrS/DI-Type1-BrP matched for age, female gender, body mass index, left ventricular ejection fraction and comorbid conditions.

Frequency of Irritable Bowel Syndrome in Patients with Brugada Syndrome and Drug-Induced Type 1 Brugada Pattern.

Irritable bowel syndrome (IBS) is one of the most widely recognized functional bowel disorders (FBDs) with a genetic component. SCN5A gene and SCN1B loci have been identified in population-based IBS cohorts and proposed to have a mechanistic role in the pathophysiology of IBS. These same genes have been associated with Brugada syndrome (BrS).

Recognition and clinical implications of high prevalence of migraine in patients with Brugada syndrome and drug-induced type 1 Brugada pattern.

Introduction: We have previously reported high 1-year prevalence of migraine in patients with atrial arrhythmias associated with DI-type 1 BrP. The present study was designed to determine the lifetime prevalence of migraine in patients with Brugada syndrome (BrS) or drug-induced type 1 Brugada pattern (DI-type 1 BrP) and control group, to investigate the demographic and clinical characteristics, and to identify clinical variables to predict underlying BrS/DI-type 1 BrP among migraineurs.

Methods And Results: Lifetime prevalence of migraine and migraine characteristics were compared between probands with BrS/DI-type 1 BrP (n = 257) and control group (n = 370).

Susceptibility to Ventricular Arrhythmias Resulting from Mutations in , , and Evaluated in hiPSC Cardiomyocytes.

Background: We report an inherited cardiac arrhythmia syndrome consisting of Brugada and Early Repolarization Syndrome associated with variants in , , and . The proband inherited the 3 mutations and exhibited palpitations and arrhythmia-mediated syncope, whereas the parents and sister, who carried one or two of the mutations, were asymptomatic.

Methods And Results: We assessed the functional impact of these mutations in induced pluripotent stem cell cardiomyocytes (hiPSC-CMs) derived from the proband and an unaffected family member.

Coexistence of atrioventricular accessory pathways and drug-induced type 1 Brugada pattern.

Background: Atrial arrhythmias, particularly atrioventricular nodal reentrant tachycardia, can coexist with drug-induced type 1 Brugada electrocardiogram (ECG) pattern (DI-Type1-BrP). The present study was designed to determine the prevalence of DI-Type1-BrP in patients with atrioventricular accessory pathways (AV-APs) and to investigate the clinical, electrocardiographic, electrophysiologic, and genetic characteristics of these patients.

Methods: One-hundred twenty-four consecutive cases of AV-APs and 84 controls underwent an ajmaline challenge test to unmask DI-Type1-BrP.

Lack of genotype-phenotype correlation in Brugada Syndrome and Sudden Arrhythmic Death Syndrome families with reported pathogenic SCN1B variants.

Background: There is limited evidence that Brugada Syndrome (BrS) is due to SCN1B variants (BrS5). This gene may be inappropriately included in routine genetic testing panels for BrS or Sudden Arrhythmic Death Syndrome (SADS).

Objective: We sought to characterize the genotype-phenotype correlation in families who had BrS and SADS with reportedly pathogenic SCN1B variants and to review their pathogenicity.

Swallow-induced syncope in 5 patients: Electrophysiologic evaluation during swallowing.

Background: We sought to characterize a cohort of participants with swallow-induced syncope (SIS) with clinical and electrophysiologic evaluations.

Methods: Using electrocardiographic monitoring and neurophysiologic methods of swallowing, we evaluated a cohort of 5 patients with SIS, 4 of whom had longitudinal follow-up.

Results: We determined electrophysiologically that the duration between the onset of swallow and a bradyarrhythmia or asystole is extremely short (2-3 seconds) in SIS.

Andersen-Tawil syndrome: Clinical presentation and predictors of symptomatic arrhythmias - Possible role of polymorphisms K897T in KCNH2 and H558R in SCN5A gene.

Background: Andersen-Tawil syndrome (ATS) is rare channelopathy caused by KCNJ2 mutation and probably KCNJ5. It is characterized by arrhythmias, neurological symptoms, and dysmorphic features. The present study retrospectively examined the characteristics of 11 unrelated families with ATS.

Atrial arrhythmias in inherited arrhythmogenic disorders.

Atrial arrhythmias are being increasingly recognized in inherited arrhythmogenic disorders particularly in patients with Brugada syndrome and short QT syndrome. Atrial arrhythmias in inherited arrhythmogenic disorders have significant epidemiologic, clinical, and prognostic implications. There has been progress in the understanding of underlying genetic characteristics and the mechanistic link between atrial arrhythmias and inherited arrhythmogenic disorders.

Female gender as independent risk factor of torsades de pointes during acquired atrioventricular block.

Background: Female gender increases the risk of torsades de pointes (TdP) in the long QT syndrome, and this increased risk is assumed to be due to their longer QT interval.

Objective: The purpose of this study was to study the interplay between gender, duration of the QT interval, and risk of TdP during AV block.

Methods: We studied 250 patients (48% women) with AV block.

Disappearance of Idiopathic Outflow Tract Premature Ventricular Contractions After Catheter Ablation of Overt Accessory Pathways.

Background: Multiple mechanisms have been proposed for idiopathic premature ventricular contractions (PVCs) originating from the outflow tracts (OTs). Recent observations such as the coexistence of these arrhythmias with atrioventricular nodal reentrant tachycardias and the association between discrete prepotentials and successful ablation sites of ventricular arrhythmias (VAs) from the OTs suggest a common link.

Objective: In this case series we draw attention to a unique association between accessory pathways (APs) and idiopathic PVCs from the OTs, disappearing after AP ablation.

Genome-Wide Association Study of Copy Number Variations in Patients with Familial Neurocardiogenic Syncope.

Neurocardiogenic syncope (NCS) is the most frequent type of syncope characterized by a self-limited episode of systemic hypotension. In this study, we conducted the first genome-wide association study testing copy number variations for association with NCS. Study population consisted of 107 consecutive patients with recurrent syncope and positive head-up tilt table testing.

High prevalence of concealed Brugada syndrome in patients with atrioventricular nodal reentrant tachycardia.

Background: Atrioventricular nodal reentrant tachycardia (AVNRT) may coexist with Brugada syndrome (BrS).

Objectives: The present study was designed to determine the prevalence of drug-induced type 1 Brugada ECG pattern (concealed BrS) in patients presenting with clinical spontaneous AVNRT and to investigate their electrocardiographic, electrophysiological, and genetic characteristics.

Methods: Ninety-six consecutive patients without any sign of BrS on baseline electrocardiogram undergoing electrophysiological study and ablation for symptomatic, drug-resistant AVNRT and 66 control subjects underwent an ajmaline challenge to unmask BrS.