The dual role of cerebral autoregulation and collateral flow in the circle of willis after major vessel occlusion
Journal
IEEE Transactions on Biomedical Engineering
Journal Volume
64
Journal Issue
8
Pages
1793-1802
Date Issued
2017
Author(s)
Abstract
Objective: Ischaemic stroke is a leading cause of death and disability. Autoregulation and collateral blood flow through the circle of Willis both play a role in preventing tissue infarction. To investigate the interaction of these mechanisms a one-dimensional steady-state model of the cerebral arterial network was created. Methods: Structural variants of the circle of Willis that present particular risk of stroke were recreated by using a network model coupled with: 1) a steady-state physiological model of cerebral autoregulation; and 2) one wherein the cerebral vascular bed was modeled as a passive resistance. Simulations were performed in various conditions of internal carotid and vertebral artery occlusion. Results: Collateral flow alone is unable to ensure adequate blood flow (>90% normal flow) to the cerebral arteries in several common variants during internal carotid artery occlusion. However, compared to a passive model, cerebral autoregulation is better able to exploit available collateral flow and maintain flows within 10% of baseline. This is true for nearly all configurations. Conclusion: Hence, autoregulation is a crucial facilitator of collateral flow through the circle of Willis. Significance: Impairment of this response during ischemia will severely impact cerebral blood flows and tissue survival, and hence, autoregulation should be monitored in this situation. ? 2016 IEEE.
Subjects
Blood
Hemodynamics
Physiological models
Tissue
Arterial stenosis
Autoregulations
Cerebral hemodynamics
Collateral flow
Ischemia
Blood vessels
anterior communicating artery
artery blood flow
Article
autoregulation
blood flow velocity
brachial artery
brain artery
brain blood flow
brain circulation
brain circulus arteriosus
brain vascular resistance
cerebral autoregulation
collateral circulation
external carotid artery
feedback system
hemodynamics
internal carotid artery occlusion
mathematical model
posterior communicating artery
simulation
thoracic aorta
tissue survival
vertebral artery stenosis
biological model
computer simulation
homeostasis
human
internal carotid artery
pathophysiology
peripheral occlusive artery disease
vertebral artery
Arterial Occlusive Diseases
Blood Flow Velocity
Carotid Artery, Internal
Cerebrovascular Circulation
Circle of Willis
Collateral Circulation
Computer Simulation
Homeostasis
Humans
Models, Cardiovascular
Vertebral Artery
SDGs
Type
journal article