Sinus Node Function in Patients With Brugada-Type ECG

Abstract

n 1992 Brugada et al reported 8 patients with right bundle branch block and persistent ST segment elevation in the right precordial leads. 1 These patients experienced episodes of syncope, and polymorphic ventricular tachycardia or VF was induced by programmed electrical stimulation (PES). It has been reported that 10-20% of cases of Brugada syndrome are caused by cardiac sodium channel mutation, 2-4 and impaired sodium channel function can explain the characteristic ST segment morphology and the occurrence of ventricular arrhythmia. [5][6][7] If mutation of the cardiac ion channel causes BS, there might be abnormal supraventricular electrophysiology. In fact, we found that patients with BS have abnormal atrial vulnerability, 8 and moreover, recent studies have shown that some cases of BS are associated with supraventricular tachyarrhythmia and sinus node dysfunction. 9-13 The present study was therefore designed to determine the characteristics of the conduction function of the sinus node and atrioventricular (AV) node in patients with a Brugada-type ECG. Methods PatientsThe subjects of this study were 59 male patients and 1 female patient with a Brugada-type ECG (13 symptomatic and 47 asymptomatic patients). The mean age of the patients was 47±10 years. Brugada-type ECG was defined as J wave (higher than 0.2 mV) and a coved-type or saddle

Atrial Electrophysiological Abnormality in Patients With Brugada Syndrome Assessed by P-Wave Signal-Averaged ECG and Programmed Atrial Stimulation

“…In 10 of these 11 patients, ventricular fibrillation was also induced by 2 or 3 right ventricular extrastimuli. 17 In 1 patient, Wolff-Parkinson-White (WPW) syndrome and atrioventricular nodal re-entrant tachycardia (AVNRT) were first diagnosed, and BS was diagnosed after accessory pathway ablation. BS was accompanied by AVNRT in another patient.…”

“…There is evidence that some patients with BS exhibit paroxysmal atrial fibrillation (AF) and/or sick sinus syndrome. [12][13][14][15][16][17] However, only a few studies have reported on the mechanisms that explain the association of BS with AF. 12,18 Thus, in this study, we evaluated the electrical abnormalities of the atrial myocardium based on the filtered P-wave duration (FPD) using the P-wave triggered signalaveraged ECG and on atrial vulnerability tested by atrial premature stimulation.…”

Prevalence of the Brugada-Type Electrocardiogram and Incidence of Brugada Syndrome in Patients With Sick Sinus Syndrome

“…9,10 There are several clinical reports of BS with sinus node dysfunction. [9][10][11][30][31][32][33] Genetic analysis could be examined in only 1 of the 4 patients with SSS and Brugada-type ECG, which was negative in our study population.…”

The Brugada Syndrome-An Update-

“…VF is more easily induced by the programmed electrical stimulation from the RV outflow tract than that from the RV apex. Prolonged sinus node recovery time and sino-atrial conduction time as well as slowed atrial conduction and atrial standstill have been reported in association with the syndrome (40).…”