Dynamics of Critical Closing Pressure Explain Cerebral Autoregulation Impairment in Acute Cerebrovascular Disease.
Cerebrovasc Dis
; : 1-9, 2024 Jul 22.
Article
en En
| MEDLINE
| ID: mdl-38964310
ABSTRACT
INTRODUCTION:
Cerebral autoregulation (CA) is impaired in acute ischemic stroke (AIS) and is associated with worse patient outcomes, but the underlying physiological cause is unclear. This study tests whether depressed CA in AIS can be linked to the dynamic responses of critical closing pressure (CrCP) and resistance area product (RAP).METHODS:
Continuous recordings of middle cerebral blood velocity (MCAv, transcranial Doppler), arterial blood pressure (BP), end-tidal CO2 and electrocardiography allowed dynamic analysis of the instantaneous MCAv-BP relationship to obtain estimates of CrCP and RAP. The dynamic response of CrCP and RAP to a sudden change in mean BP was obtained by transfer function analysis. Comparisons were made between younger controls (≤50 years), older controls (>50 years), and AIS patients.RESULTS:
Data from 24 younger controls (36.4 ± 10.9 years, 9 male), 38 older controls (64.7 ± 8.2 years, 20 male), and 20 AIS patients (63.4 ± 13.8 years, 9 male) were included. Dynamic CA was impaired in AIS, with lower autoregulation index (affected hemisphere 4.0 ± 2.3, unaffected 4.5 ± 1.8) compared to younger (right 5.8 ± 1.4, left 5.8 ± 1.4) and older (right 4.9 ± 1.6, left 5.1 ± 1.5) controls. AIS patients also demonstrated an early (0-3 s) peak in CrCP dynamic response that was not influenced by age.CONCLUSION:
These early transient differences in the CrCP dynamic response are a novel finding in stroke and occur too early to reflect underlying regulatory mechanisms. Instead, these may be caused by structural changes to cerebral vasculature.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Idioma:
En
Revista:
Cerebrovasc Dis
Asunto de la revista:
ANGIOLOGIA
/
CEREBRO
Año:
2024
Tipo del documento:
Article