Bilateral vertebral artery disease: transcranial Doppler assessment of the hemodynamic vulnerability to changes in posture.
Ultrasound Med Biol
; 32(10): 1485-91, 2006 Oct.
Article
em En
| MEDLINE
| ID: mdl-17045868
ABSTRACT
Posture changes may cause hemodynamic ischemic events, particularly in severe vertebrobasilar artery disease. It may be difficult and not without risk to prove this vulnerability to changes in posture during angiography. Therefore, TCD monitoring with passive tilting (PT) was used to evaluate cerebral hemodynamics distally to severe bilateral vertebral artery disease (BVAD). PCA flow velocity changes and dynamic cerebral autoregulation (DCA) were analyzed in supine and upright position. Despite a significant autoregulatory deficit distally to BVAD, the posterior cerebral blood supply seemed to be sufficiently maintained as long as systemic blood pressure changes were within normal limits. Posterior cerebral flow velocities, however, were significantly diminished when PT detected a systemic hypotension in upright position. This study proves the feasibility to combine PT and TCD monitoring of the PCA in patients with BVAD. In vertebrobasilar artery disease, the examination of spontaneous and tilt-induced autoregulatory responses could support the evaluation of a risk for hemodynamic ischemia.
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Bases de dados:
MEDLINE
Assunto principal:
Postura
/
Insuficiência Vertebrobasilar
/
Circulação Cerebrovascular
/
Ultrassonografia Doppler Transcraniana
Limite:
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Ultrasound Med Biol
Ano de publicação:
2006
Tipo de documento:
Article
País de afiliação:
Alemanha