Sympathetic alternans. Evidence for arterial baroreflex control of muscle sympathetic nerve activity in congestive heart failure.
Circulation
; 95(2): 316-9, 1997 Jan 21.
Article
em En
| MEDLINE
| ID: mdl-9008442
ABSTRACT
Alternation in the amplitude of muscle sympathetic nerve activity (MSNA) was documented in three patients with severe heart failure. In the index patient with pulsus alternans, the amplitude of MSNA was inversely related to changes in the preceding diastolic pressure with a lag time of 1.2 to 1.3 seconds, indicating that oscillations in burst amplitude are determined primarily by changes in this component of blood pressure. Spectral analysis of the blood pressure and MSNA signals identified two spectral peaks, one at the cardiac frequency and a second peak, with greater spectral power, at the alternans frequency (ie, at half the heart rate). The latter peak for both blood pressure and MSNA disappeared when alternans was abolished by nitroglycerin. The presence of sympathetic alternans in synchrony with pulsus alternans and the rapid transduction of changes in the diastolic blood pressure afferent signal to the amplitude of sympathetic outflow indicate that the arterial baroreflex control of MSNA must be active and rapidly responsive in human heart failure.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Artérias
/
Sistema Nervoso Simpático
/
Barorreflexo
/
Insuficiência Cardíaca
/
Músculos
Tipo de estudo:
Prognostic_studies
Limite:
Adult
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Circulation
Ano de publicação:
1997
Tipo de documento:
Article
País de afiliação:
Canadá