Prevalence of Right Bundle-Branch Block and Right Precordial ST-Segment Elevation (Brugada-Type Electrocardiogram) in Japanese Children

Abstract

n 1992, Brugada et al described 8 cases of aborted sudden death in patients without demonstrable structural heart disease, but with a peculiar electrocardiogram (ECG) pattern consisting of right bundle-branch block (RBBB) and ST-segment elevation in leads V1 to V3. 1 Three of 8 patients in this report were children, and familial occurrence was recognized. Since then, a few case reports have been published on this syndrome in young populations. [2][3][4] Brugada syndrome may cause sudden death in children, even in the first few months of life where it may be misdiagnosed as sudden infant death syndrome. The Brugada-type ECG is not rare in the adult Japanese population (0.14 to 0.70%). [5][6][7] However, the prevalence of this type of ECG in schoolchildren remains unclear. We evaluated the prevalence of Brugada-type ECG, incomplete RBBB (IRBBB) and complete RBBB (CRBBB) in Japanese schoolchildren stratified according to age. Circulation Journal Vol.68, April 2004 Methods ECG DefinitionsAll ECGs were recorded at standard gain (1 mV/10 mm) and paper speed (25 mm/s). An ECG was considered to be Brugada-type when the 12-lead ECG fully met the criteria for the Brugada syndrome as recently published in a consensus report. 8 To compare the prevalence with previous reports of healthy populations, we defined "Brugada-like" ECG as follows. The 12-lead ECG showed RBBB (rsR' or Rsr' pattern in V1 lead) and ST-segment elevation in the right precordial leads. The ST-segment elevation was defined as an elevation of the J point of ≥0.1 mV in leads V1 through V3. According to the configuration, ST-segment elevations were designated as either coved or saddle-back.Complete RBBB was defined as a QRS duration ≥0.12 s, with an RsR' configuration and IRBBB was defined as a QRS duration <0.12 s, with an rSr' configuration in the right precordial leads.The ECG records of all study subjects were reviewed by Yamakawa, without any information about the subjects including age, sex, or family history of sudden death. Ishikawa and Sumita reviewed those records on which judgments had been made, and they concurred with the judgments. Study SubjectsThe study population consisted of 20,387 young We considered right bundle-branch block and ST-segment elevation of the J point of ≥0.1 mV in leads V1 through V3 as Brugada-like ECG, and an ECG was considered to be Brugada-type when the 12-lead ECG fully meet the criteria for the Brugada syndrome as recently published in a consensus report. Only 2 children (0.0098%, 95% confidence interval (CI): 0 to 0.023%) completely conformed to the criteria for Brugada-type ECG. Brugada-like ECG was found in 11 (10 male) of 20,387 children (0.054%, 95% CI: 0.022 to 0.086%). The prevalence in males was significantly higher than that in females, even in children (0.096% vs 0.010%, p=0.012). Stratified according to age, there was tendency for the prevalence of Brugada-like ECG to increase up to puberty (first graders, 0.01%; fourth graders, 0.05%; seventh graders, 0.08%; tenth graders, 0.23%; p=0.068). ConclusionThe pre...

Bradycardia-Dependent ECG Changes in Brugada Syndrome

“…Although the prevalence of BS is higher in Asian countries, [28][29][30][31][32] the prevalence of Brugada-type ECGs in Japan is only 0.14-1.22%. [29][30][31][32] All patients in the present study were recruited from only 1 institute. Therefore, further prospective studies using a large number of patients are needed to validate the present findings.…”

The genetic basis of Brugada syndrome: A mutation update

“…The prevalence of the disease is difficult to estimate, as asymptomatic patients are only identified by accidental ECG recording, but it is estimated to be approximately 5:10,000 [Blangy et al, 2005;Bozkurt et al, 2006;GervacioDomingo et al, 2008;Ito et al, 2006] and higher in South East Asia, where BrS occurs endemically [Nademanee, 1997]. Among children, the occurrence is much lower than in adults, but the gender difference is still evident with more boys being affected than girls [Yamakawa et al, 2004].…”

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

“…The typical Brugada-type (type 1) ECG is reported to be more prevalent in adults (0.05-0.28%) [15][16][17][18][19][20] than in adolescents (0.005-0.06%). 15,[21][22][23] Our results in SSS patients, which included only adult patients, showed more prevalence (0.82%) than in the general population of adults ( Table 2). Genetic factors might influence the expression of both phenotypes; BS and SSS.…”

“…[15][16][17][18][19][20][21][22][23] However, this prevalence is different depending on the age of the population. The typical Brugada-type (type 1) ECG is reported to be more prevalent in adults (0.05-0.28%) [15][16][17][18][19][20] than in adolescents (0.005-0.06%).…”