Hemodynamic role of the circle of Willis in stenoses of internal carotid arteries. An analytical solution of a linear model

2000 ◽  
Vol 33 (4) ◽  
pp. 395-405 ◽  
Author(s):  
F. Cassot ◽  
M. Zagzoule ◽  
J.-P. Marc-Vergnes
2018 ◽  
Vol 124 (5) ◽  
pp. 1326-1332 ◽  
Author(s):  
Erika Iwamoto ◽  
Joshua M. Bock ◽  
Darren P. Casey

Shear-mediated dilation in peripheral conduit arteries is blunted with sympathetic nervous system (SNS) activation; however, the effect of SNS activation on shear-mediated dilation in carotid arteries is unknown. We hypothesized that SNS activation reduces shear-mediated dilation in common and internal carotid arteries (CCA and ICA, respectively), and this attenuation is greater in the ICA compared with the CCA. Shear-mediated dilation in the CCA and ICA were measured in nine healthy men (24 ± 1 yr) with and without SNS activation. Shear-mediated dilation was induced by 3 min of hypercapnia (end‐tidal partial pressure of carbon dioxide +10 mmHg from individual baseline); SNS activity was increased with lower body negative pressure (LBNP; −20 mmHg). CCA and ICA measurements were made using Doppler ultrasound during hypercapnia with (LBNP) or without (Control) SNS activation. LBNP trials began with 5 min of LBNP with subjects breathing hypercapnic gas during the final 3 min. Shear-mediated dilation was calculated as the percent rise in peak diameter from baseline diameter. Sympathetic activation attenuated shear-mediated dilation in the ICA (Control vs. LBNP, 5.5 ± 0.7 vs. 1.8 ± 0.4%, P < 0.01), but not in the CCA (5.1 ± 1.2 vs. 4.2 ± 1.0%, P = 0.31). Moreover, absolute reduction in shear-mediated dilation via SNS activation was greater in the ICA than the CCA (−3.6 ± 0.7 vs. −0.9 ± 0.8%, P = 0.02). Our data indicate that shear-mediated dilation is attenuated during LBNP to a greater extent in the ICA compared with the CCA. These results potentially provide insight into the role of SNS activation on cerebral perfusion, as the ICA is a key supplier of blood to the brain. NEW & NOTEWORTHY We explored the effect of acute sympathetic nervous system (SNS) activation on shear-mediated dilation in the common and internal carotid arteries (CCA and ICA, respectively) in young healthy men. Our data demonstrate that hypercapnia-induced vasodilation of the ICA is attenuated during lower body negative pressure to a greater extent than the CCA. These data may provide novel information related to the role of SNS activation on cerebral perfusion in humans.


2020 ◽  
Vol 39 (8) ◽  
pp. 1527-1535
Author(s):  
Mucize Eric Ozdemir ◽  
Oya Demirci ◽  
Hatice Akay Ozturkmen ◽  
Nuray Bakal Ulusoy ◽  
Karolin Ohanoglu ◽  
...  

Author(s):  
Akmal Zahra ◽  
Hanan Al-Abboh ◽  
Yousif Habeeb ◽  
Adekunle Adekile

Moyamoya is a progressive cerebrovascular disease associated with stenosis or occlusion of the arteries of the Circle of Willis. It is uncommon in thalassemia. We present a 9-year-old girl, with HbEβ-thalassemia, who presented with headache, vomiting and episodes of transient hemiparesis with complete occlusion internal carotid arteries.


2018 ◽  
Author(s):  
Bruno Bandeira ◽  
Roberto Lages ◽  
Zeferino Demartini Júnior ◽  
Gelson Koppe ◽  
Luana Gatto

Author(s):  
Novikova I.N. ◽  
Popova T.F. ◽  
Gribacheva I.A. ◽  
Petrova E.V. ◽  
Marushchak A.A. ◽  
...  

Moya-Moya disease is a rare progressive chronic cer-ebrovascular disease characterized by a narrowing of the lumen of the intracranial segments of the internal carotid arteries, as well as the initial segments of the anterior and middle cerebral arteries with the devel-opment of a network of small vascular anastomoses. Violations of blood supply due to occlusion lead to the development of ischemic strokes in the correspond-ing pools, and ruptures of vascular anastomoses - to the development of hemorrhagic strokes, causing a variety of neurological disorders. The article presents a clinical case of Moya-Moya disease in a 31-year-old patient. The disease was manifested by acute disorders of cerebral circulation in ischemic and hemorrhagic types. The diagnosis was made in accordance with the diagnostic criteria of the disease based on the data of endovascular cerebral angiography.


2001 ◽  
Vol 176 (1) ◽  
pp. 263-264 ◽  
Author(s):  
Rodolfo A. Ibarra ◽  
Prabhakar Kesava ◽  
John L. Fewins

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1119.3-1120
Author(s):  
L. Nacef ◽  
H. Ferjani ◽  
H. Riahi ◽  
Y. Mabrouk ◽  
E. Labbene ◽  
...  

Background:Patients with rheumatoid arthritis (RA) are at higher cardiovascular risk (CVR) than the general population due to chronic inflammation. Several factors, both modifiable and non-modifiable, can increase this risk. Intima-media thickness (IMT) was considered as a marker for atherosclerosis.Objectives:This study aimed to identify predictor factors of increasing IMT.Methods:The prospective study was carried out on patients with RA who met the 2010 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) classification criteria. These patients were followed in the rheumatology department of the Kassab Institute. The socio-demographic data, biological and immunological parameters were collected.Framingham’s score quantified the cardiovascular risk at 10-years. Carotid Ultrasonography (US) using a high resolution B mode carotid measured intima-media thickness (IMT) as a subclinical marker of atherosclerosis. Carotid US was performed in the supine position, according to American Society of Echocardiography guidelines. IMT was measured in the left (LCC) and right (RCC) common carotid arteries, the left (LIC) and right (RIC) internal carotid arteries, and the left (LEC) and right (RIC) internal carotid arteries. An increased IMT was defined as ≥0.9 mm.We analyzed data by the SPSS statistical package. A p-value <0.05 was considered significant.Results:Of the 47 patients surveyed, 78.7% were female. The mean age was 52.5 ±11.06 [32-76]. The duration disease was 86.25 ±63 months [5-288] and was erosive in 81.6% of cases. The rheumatoid factor (RF) was positive in 57.8% of patients, and citrullinated antipeptide antibodies (ACPA) were present in 62.2%. Eight patients had a previous CV history (hypertension, diabetes or dyslipidemia) and 16.4% were active smokers. Among women, 43.6% were postmenopausal. ITM was significantly higher in men at LIC (0.037) and LEC (0.025). Older age was associated with increased ITM in LIC (p=0.046; r=0.295), LEC (p=0.05; r=0.412), RCC (p=0.034; r=0.317), and REC (p=0.009; r=0.382). The ITM for LCC, LIC, LEC, RCC, RIC, and REC was higher in postmenopausal women, with no significant difference (p=0.782, p=0.208, p=0.877, r=0.734, p=0.808, p=0.437, respectively).Among the modifiable factors, active smoking was associated with a higher ITM at the REC level (p=0.047). However, weight was not associated with an increased ITM (LCC: p=0.092; LIC: p=0.985; LEC: p=0.952; RCC: p=0.744; RIC: p=0.210; REC: p=0.510). In our study, there was no significant association between DAS28 disease activity or inflammatory marks and ITM (LCC: p=0.784; LIC: p=0.316; LEC: p=0.420; RCC: p=0.784; RIC: p=0.484; REC: p=0.754).Conclusion:In our study, the non-modifiable factors associated with increased ITM were advanced age and male gender. The modifiable factor impacting ITM was primarily active smoking. Surprisingly, disease activity and biological inflammation did not influence ITM.References:[1]S. Gunter and al. Arterial wave reflection and subclinical atherosclerosis in rheumatoid arthritis. Clinical and experimental rheumatology 2018; 36: clinical e.xperimental.[2]Aslan and al. Assessment of local carotid stiffness in seronegative and seropositive rheumatoid Arthritis. Scandinavian cardiovascular journal, 2017.[3]Martin i. Wah-suarez and al, carotid ultrasound findings in rheumatoid arthritis and control subjects: a case-control study. Int j rheum dis. 2018;1–7.Disclosure of Interests:None declared


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