Heart rate variability and repolarization characteristics in symptomatic and asymptomatic Brugada syndrome.
Europace
; 19(10): 1730-1736, 2017 Oct 01.
Article
em En
| MEDLINE
| ID: mdl-27738060
ABSTRACT
AIM:
Modulation of ST-segment elevation (STE) and tachyarrhythmic events by the autonomic nervous system (ANS) has been reported in patients with Brugada syndrome (BS). This study examined and compared the autonomic characteristics and STE in symptomatic vs. asymptomatic patients with BS. METHODS ANDRESULT:
We studied 40 symptomatic and 78 asymptomatic patients (mean age = 46.1 ± 13.7 years; 88 men) who underwent 24 h, 12-lead electrocardiograms, and exercise and a head-up tilt tests. Heart rate variability was examined and STE was measured at 5 points between 100 and 140 ms after the onset of 1 min averaged QRS complexes, and the type 1 Brugada pattern was automatically identified. 'Type 1 Brugada burden' was the percentage of averaged type 1 complexes. All measurements were made over 24 h, and during day and night times. During daytime, the variation coefficients of standard deviation of normal-to-normal intervals were 39.0 ± 12.3 vs. 34.1 ± 14.5 ms (P< 0.05) and high frequency normalized units were 39.9 ± 16.9 vs. 33.9 ± 16.2% (P< 0.05) in symptomatic vs. asymptomatic patients, respectively. ST-segment elevation was similar in symptomatic and asymptomatic patients at all time points. The type 1 Brugada burden in V2 was 38.7 ± 33.6% in the symptomatic vs. 24.3 ± 35.2% in the asymptomatic sample, a statistically non-significant difference.CONCLUSION:
This analysis of ANS did not identify sensitive predictors of arrhythmic events in patients with BS. We observed, however, greater fluctuations in sinus node response to ANS in symptomatic patients. The type 1 Brugada electrocardiographic pattern was not as reliable a predictor of arrhythmic risk as previously reported.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sistema Nervoso Autônomo
/
Potenciais de Ação
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Síndrome de Brugada
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Coração
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Sistema de Condução Cardíaco
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Frequência Cardíaca
Tipo de estudo:
Diagnostic_studies
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Observational_studies
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Prognostic_studies
Limite:
Adult
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Europace
Assunto da revista:
CARDIOLOGIA
/
FISIOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
França
País de publicação:
ENGLAND
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ESCOCIA
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GB
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GREAT BRITAIN
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INGLATERRA
/
REINO UNIDO
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SCOTLAND
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UK
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UNITED KINGDOM