scholarly journals Relationship between haemodynamic impairment and collateral blood flow in carotid artery disease

2017 ◽  
Vol 38 (11) ◽  
pp. 2021-2032 ◽  
Author(s):  
Nolan S Hartkamp ◽  
Esben T Petersen ◽  
Michael A Chappell ◽  
Thomas W Okell ◽  
Maarten Uyttenboogaart ◽  
...  

Collateral blood flow plays a pivotal role in steno-occlusive internal carotid artery (ICA) disease to prevent irreversible ischaemic damage. Our aim was to investigate the effect of carotid artery disease upon cerebral perfusion and cerebrovascular reactivity and whether haemodynamic impairment is influenced at brain tissue level by the existence of primary and/or secondary collateral. Eighty-eight patients with steno-occlusive ICA disease and 29 healthy controls underwent MR examination. The presence of collaterals was determined with time-of-flight, two-dimensional phase contrast MRA and territorial arterial spin labeling (ASL) imaging. Cerebral blood flow and cerebrovascular reactivity were assessed with ASL before and after acetazolamide. Cerebral haemodynamics were normal in asymptomatic ICA stenosis patients, as opposed to patients with ICA occlusion, in whom the haemodynamics in both hemispheres were compromised. Haemodynamic impairment in the affected brain region was always present in symptomatic patients. The degree of collateral blood flow was inversely correlated with haemodynamic impairment. Recruitment of secondary collaterals only occurred in symptomatic ICA occlusion patients. In conclusion, both CBF and cerebrovascular reactivity were found to be reduced in symptomatic patients with steno-occlusive ICA disease. The presence of collateral flow is associated with further haemodynamic impairment. Recruitment of secondary collaterals is associated with severe haemodynamic impairment.

2020 ◽  
pp. 68-68
Author(s):  
Vladimir Manojlovic ◽  
Djordje Milosevic ◽  
Nebojsa Budakov ◽  
Dragan Nikolic

Introduction/Objective. Circle of Willis (CoW) provides the most significant collateral flow in the presence of significant stenosis or occlusion of internal carotid artery. In terms of collateral flow ?incomplete? type and ?complete? type of CoW can be recognized. Patients with carotid artery disease with incomplete CoW have lower cerebrovascular reactivity and higher risk for stroke. Cerebrovascular reactivity refers to the residual capacity of dilatation of cerebral blood vessels in the condition of insufficient blood flow. In this study we analyzed changes in cerebrovascular reactivity after carotid endarterectomy in asymptomatic patients with respect to complete and incomplete CoW morphology. Methods. In this study in 97 patients with asymptomatic carotid artery disease we measured cerebrovascular reactivity before and after carotid endarterectomy by using method of ?apnea test? and ? Breath Hold Index? (BHI). Patients were divided into two following groups: patients with ?complete? CoW and ?incomplete? CoW based on non-contrast magnetic resonance angio performed previously to the operation. Descriptive statistics, univariate analysis, and ANOVA for comparison of BHI values between groups were used. Results. Results showed significant increase in cerebrovascular reactivity at the side of stenosis in both groups of patients with complete CoW (BHI value increased from 0,897 to 1.090; F(1.65) = 30.788, p < 0.0005, parc. ?2 = 0.321) and incomplete CoW (BHI value increased from 0.690 to 1.010; F ( 1.27 ) = 62.318 , p < 0.0005, parc. ?2 = 0.698) and the more significant increase in the group of incomplete CoW compared to the group with complete CoW (F (1.92 ) = 4.557 , p =0.035 , parc. ?2 =0.047) Conclusion. In most asymptomatic patients, cerebrovascular reactivity restores to normal following carotid endarterectomy. Parameters of cerebrovascular reactivity are lower in patients with incomplete CoW and the increase after carotid endarterectomy is more significant in such patients.


2017 ◽  
Vol 44 (2) ◽  
pp. 143-150 ◽  
Author(s):  
Nolan S. Hartkamp ◽  
Reinoud P.H. Bokkers ◽  
M.J.P. van Osch ◽  
Gert J. de Borst ◽  
Jeroen Hendrikse

Ophthalmology ◽  
1991 ◽  
Vol 98 (4) ◽  
pp. 548-552 ◽  
Author(s):  
Wolfgang E. Lieb ◽  
Patrick M. Flaharty ◽  
Robert C. Sergott ◽  
Rickey D. Medlock ◽  
Gary C. Brown ◽  
...  

Neurology ◽  
2017 ◽  
Vol 90 (4) ◽  
pp. e307-e315 ◽  
Author(s):  
Simona Lattanzi ◽  
Luciano Carbonari ◽  
Gabriele Pagliariccio ◽  
Marco Bartolini ◽  
Claudia Cagnetti ◽  
...  

ObjectiveTo evaluate in patients with TIA and ipsilateral high-grade internal carotid artery (ICA) stenosis whether changes in cognitive performance and cerebral hemodynamics occurred after carotid endarterectomy (CEA) and to explore their relationship.MethodsParticipants were patients who underwent CEA, had TIA within the last 6 months, and had an ipsilateral severe ICA stenosis. Coloured Progressive Matrices (CPM) plus Complex Figure Copy Test (CFCT) and phonemic (ph) plus categorical (ca) Verbal Fluency (VF) tests were performed to assess right and left hemisphere cognitive functions, respectively. Hemodynamics was assessed with transcranial Doppler ultrasonography by means of the cerebral vasomotor reactivity (CVR) to hypercapnia.ResultsA total of 137 patients were included. Before CEA, patients with right ICA obtained lower scores on the CPM and CFCT; patients with left ICA stenosis performed worse on the phonemic and categorical VF tests. The CVR was decreased on the side of the stenosis. At 6 months from CEA, CVR and cognitive performance were significantly improved. The performance change in cognitive tests exploring the revascularized hemisphere was positively associated with the ipsilateral CVR variation (CPM: R2 for linear regression = 0.759, adjR2 = 0.737; CFCT: R2 = 0.734, adjR2 = 0.710; (ph)VF: R2 = 0.774, adjR2 = 0.749; (ca)VF: R2 = 0.732, adjR2 = 0.703).ConclusionCognitive performance was enhanced at 6 months since CEA, and the improvement was related to the CVR increase. Cerebral hemodynamics may be an independent and potentially reversible determinant of cognitive dysfunction in severe carotid artery disease.


Sign in / Sign up

Export Citation Format

Share Document