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Objective: To investigate the working memory of patients with cervicocerebral artery stenosis and its change after stenting., Methods: 35 patients with cervicocerebral artery stenosis (≥50% with related symptoms of cerebral ischemia, or ≥70% with or without related symptoms of cerebral ischemia) underwent endovascular stenting. Working memory of all 35 patients before and within 3 weeks of stenting was evaluated by memory quotient (MQ) scores. Change in regional cerebral blood flow (rCBF) was assessed by single photon emission CT (SPECT) for 13 of the patients. MQ scores were compared according to location and degree of stenosis for all patients, as well as changes in rCBF for the 13 patients., Results: Mean MQ scores were significantly lower than normal for patients with carotid artery stenosis alone and for patients with carotid stenosis in addition to vertebrobasilar and/or subclavical stenosis, but not for patients with vertebrobasilar and/or subclavical stenosis. MQ scores were significantly increased after stenting for all patients, especially those with carotid stenosis. There was no significant difference between patients with moderate stenosis and those with severe (>70%) stenosis in MQ increments pre- and post-stenting (p=0.085). Nine of the 13 patients who received SPECT showed an improvement in rCBF after stenting, and their MQ increments were significantly higher than those without an improvement in rCBF (p=0.020)., Conclusions: Working memory impairment can be observed in patients with cervicocerebral artery stenosis, especially those with carotid stenosis. Endovascular stenting of stenosis might improve the impairment by alleviating cerebral perfusion deficit.

Objective: Whether small vessel infarction (SVI) correlates with large arterial lesion is under debate. The aim of the present study was to analyze the relationship between the single SVI in carotid territory by diffusion weight imaging (DWI) and arterial lesion by contrast enhanced magnetic resonance angiography (CEMRA)., Methods: Sixty patients with acute cerebral infarction underwent DWI within 7 days and CEMRA within 2 weeks after onset. They were divided into 2 groups of patients with and without single SVI. The clinical and magnetic resonance image features were compared between two groups., Results: Lesions of ipsilateral extracranial carotid artery were detected in 10 patients of SVI groups (36%) versus 8 patients (25%) of non-SVI group (P = 0.54). Incidence of intracranial vascular lesion in single SVI group (32%) was slightly lower than that of non-SVI group (47%) (P = 0.52). And 46 patients (77%) were assessed on plaque of carotid artery. Incidence of ipsilateral carotid artery plaque (44%) was higher in single SVI group than that of non-SVI group (35%) (P = 0.76). And the incidence of vulnerable plaque in single SVI group (26%) was similar to that of non-SVI group (22%) (P = 0.73)., Conclusion: SVI has not a single underlying mechanism of stroke. However, further studies with a large number of patients are warranted.

Objectives: To study the relationship between serum levels of some inflammatory markers and stability of carotid plaques in the patients with carotid plaques and evaluate the ability of each serum marker in identifying vulnerable carotid plaques., Methods: The study included 65 consecutive patients with carotid plaques confirmed by imaging examinations from March 2008 to March 2010. All the patients were classified as stable plaques group (n = 21) and unstable plaques group (n = 44) according to the characteristic findings of the plaques in MRI such as the thickness of fibrous cap, the existence of large lipid core and the intra-plaque hemorrhage. The patients of unstable plaques group were further classified as unruptured plaques group (n = 29) and rupture plaques group (n = 15) according to the integrity of fibrous cap. Serum levels of soluble cluster of differentiation 40 ligand (sCD40L), matrix metalloproteinase 9 (MMP-9) and pregnancy-associated plasma protein A (PAPP-A) were determined by ELISA., Results: Serum levels of sCD40L and MMP-9 in patients of unstable plaques group, unruptured plaques group and rupture plaques group were all significantly enhanced compared to individuals of stable plaques group (SCD40L: χ(2) = 6.45, 12.04 and 16.23, P < 0.01; MMP-9; F = 2.55, 5.10 and 4.69, P < 0.05). Serum levels of PAPP-A in patients of unstable plaques group and rupture plaques group were all significantly enhanced compared to individuals of stable plaques group (χ(2) = 11.71 and 13.55, P < 0.05). Serum levels of PAPP-A in patients of rupture plaques group were significantly enhanced compared to individuals of unruptured plaques group (χ(2) = 13.19, P = 0.000). sCD40L ≥ 673.22 ng/L (OR = 22.47, 95%CI: 2.11 - 239.81, P = 0.010), MMP-9 ≥ 84.09 µg/L (OR = 10.01, 95%CI: 1.74 - 57.78, P = 0.010) and PAPP-A ≥ 0.101 µg/L (OR = 14.29, 95%CI: 2.69 - 75.90, P = 0.002) were all significantly correlated with the vulnerability of carotid plaques., Conclusions: There appear to be a relationship between the serum levels of sCD40L, MMP-9 and PAPP-A and the stability of carotid plaques in patients with carotid plaques. High serum levels of the above-mentioned markers may indicate that the plaques were vulnerable or ruptured.

Objective: To study the necessity, feasibility, security of carotid angioplasty and stenting (CAS) for symptomatic carotid stenosis combined with kinking., Methods: Twelve patients with symptomatic carotid stenosis and kinking demonstrated by digital subtraction angiography (DSA) received CAS from December 2003 to December 2009. There were 9 male and 3 female patients, age ranged from 59 to 77 years (mean 69.3 years). All the patients' clinical, imaging, intervention and follow up data were collected and analyzed., Results: All CAS procedures were successfully performed with 14 self-expandable stents placed. The mean degree of stenosis was reduced from 85.6% before stenting to 11.2% after stenting, the angle of kinking, according to Metz' category, were improved from less than 90° to more than 120° in each case. No perioperative procedure related stroke and transient ischemic attack (TIA) occurred. The clinical symptoms and signs of cerebral ischemia were improved or disappeared for all patients. During follow-up of these 12 patients for 6 to 72 months, one patient experienced ipsilateral carotid territory TIA and another patient experienced contralateral carotid territory TIA. DSA follow up of 5 patients demonstrated 1 case with in-stent restenosis and arterial kinking remote to the stent of internal carotid artery. CAS were performed again and CT angiography follow up demonstrated no kinking and restenosis 2 years after the intervention. Duplex scan of the other 7 patients demonstrated neither kinking nor restenosis., Conclusions: CAS seems to be feasible and safe for the patients with symptomatic kinking and stenosis, and maybe helpful to lower the risk of cerebral ischemia, but further study is needed.

We investigated serial changes of circulation platelet activation markers in 40 patients undergoing carotid artery stenting under the protection of dual antiplatelet therapy and filter devices. Monocyte-platelet aggregates and PAC-1 (a marker specific for activated glycoprotein IIb/IIIa) analyzed by flow cytometry were determined in patients with symptomatic stenosis undergoing elective carotid artery stenting. Blood samples were obtained immediately before stent implantation and 0.5 hours, 18 hours, and 6 days after the procedure, respectively. All patients were already on dual antiplatelet therapy of aspirin and clopidogrel before carotid artery stenting, and all were stented with embolic protection devices. Both circulation monocyte-platelet aggregates and PAC-1 did not change significantly at the various time points after the procedure. Serial changes of monocyte-platelet aggregates and PAC-1 analyzed by flow cytometry fail to indicate the occurrence of platelet activation after carotid artery stenting under the treatment with dual antiplatelet therapy before carotid artery stenting and the application of embolic protection devices during the procedure.

Objective: To observe the changes of nitric oxide (NO) and endothelin (ET) serum level in the Guangxi BA-MA minipigs whose carotid arteries were injured by balloon denudation and in the patients with carotid stent assisted angioplasty., Methods: Twelve Guangxi BA-MA minipigs were chosen. High fat/cholesterol feeding and endovascular balloon denudation were used to create a carotid artery atherosclerotic stenosis animal model. Blood samples were collected from peripheral veins before starting the procedure, and again, at 2 and 3 weeks after the procedure, respectively. Serum NO and ET concentrations of blood samples were tested. Nineteen patients with carotid artery stenosis who underwent stent assisted angioplasty were randomly selected, and their serum NO and ET were tested using the same methods as above., Results: In the animal group, there was a significant decrease of mean NO concentration at 2 weeks after carotid injury (t-test, P < 0.05), however, no significant change of ET was observed. A very significant increase of ET was observed at 3 weeks after the procedure (t-test, P < 0.01). In the patient group, there were no significant differences among serum NO or ET concentration of peripheral vein blood before, immediately after, and 6 h after the endovascular treatment., Conclusions: In this study, a decrease of NO concentration and an increase of ET concentration of peripheral vein blood are found in BA-MA minipigs after carotid arteries are injured by balloon denudation, which might be a cue for the formation of atherosclerosis. However, no significant changes are observed in this group of patients who underwent carotid angioplasty treatment. Therefore, further studies are needed.

Objectives: To explore influencing factors of regional cerebral blood flow (rCBF) in geriatric carotid stenosis, and to analyze changes of rCBF and clinical symptoms after carotid stenting., Methods: During August 2005 and April 2008, 68 geriatric patients of carotid stenosis having SPECT examination in our hospital were retrospectively studied, whose diagnosis was approved by angiography. Correlated rCBF was compared separately in different stenotic degrees of carotid stenosis, in unilateral or bilateral stenosis, accompanied with vertebrobasilar stenosis (VBS) or not, with collateral circulation or not, before and after carotid stenting., Results: When patients of unilateral carotid stenosis were grouped by different clinical factors, cases of patients with reduced rCBF were compared using chi(2) test: the P value was 0.046 and 0.020 when comparing group of stenotic degree 90% - 99% with group 70% - 89% and group 50% - 69%; the P value was 0.927 between group accompanied with VBS and group without; the P value was 0.222 between group with collateral circulation and group without. When comparing reduced rCBF cases between unilateral and bilateral carotid stenosis, the P value was 0.046. After carotid stenting, 76% of patients had their rCBF improved, and also the scores of presenting symptoms evaluated by modified Rankin scale were elevated from 1.4 +/- 0.7 on admission to 0.4 +/- 0.3 postoperatively (P < 0.001)., Conclusions: The research indicates that higher stenotic degree and bilateral carotid stenosis may cause rCBF decrease in geriatric carotid stenosis. Carotid stenting may improve rCBF and change clinical symptoms significantly.

Objectives: To establish a theoretical model for the tortuosity of internal carotid artery and summarize the hemodynamic rule of blood flow in a tortuous artery. To explore the relationship of cerebral ischemia and tortuous internal carotid artery., Methods: Taking the internal carotid artery as a prototype, a geometric model of a tortuous artery was constructed according to the normal physiological and anatomical parameters of internal carotid artery. The boundary conditions and calculation conditions of blood flow are proposed. The numerical simulation of the blood flow in the tortuous artery is carried out with finite element method. Hemodynamic parameters of internal carotid artery were measured in 15 cases with the tortuosity of internal carotid artery and in 15 cases of normal control group. Blood pressure was measured by microcatheter connecting a pressure transducer at internal carotid artery, pre-tortuous and post-tortuous artery. The diameter and length of the above artery were measured and calculated by DSA machine., Results: Numerical simulation results indicated pressure drop of blood flow and elongated length of artery is increased with diminution of the angle of tortuous artery. Clinical measurement data disclosed the same trend in the same curve as numerical simulation., Conclusion: The elongation and tortuosity of internal carotid artery results in decrease of blood pressure in the distal segment of tortuous internal carotid artery, kinking of internal carotid artery may be one of factors related to attack of cerebral ischemia on certain conditions.

Background Carotid endarterectomy (CEA) is currently the preferred treatment for severe carotid kinking and stenosis. Kinking is generally believed to be a relative contraindication for endovascular stent placement. This article aims to study the necessity, feasibility and security of carotid angioplasty and stenting (CAS) for symptomatic carotid kinking combined with stenosis, and summarize clinical experience of this disease according to therapeutic results. Methods Twenty - two cases with symptomatic carotid kinking and high-grade stenosis demonstrated by digital subtraction angiography (DSA) were performed CAS. Their clinical manifestations, imaging features, procedure safety and follow-up data were collected and retrospectively analyzed. All patients understood CEA and voluntarily received CAS. Results Twenty - two cases with carotid kinking and stenosis were all successfully performed CAS (the success rate was 100%) without stent-related disability or mortality. Twenty-four self-expandable stents were implanted. The mean degree of stenosis was reduced from 85.63% before stenting to 11.25% after stenting and the angles of kinking were improved from < 90° to > 120° (Metz' category). During the period of hospitalization, no transient ischemic attack (TIA) or cerebral infarction occurred, and the clinical symptoms and signs of ischemia, such as dizziness and headache, were improved or disappeared. Besides, no permenant complications or deaths happened. All cases were followed up from 6 to 72 months, among whom 1 patient experienced contralateral carotid TIA, and 2 patients experienced ipsilateral carotid TIA (one indicated aspirin resistance in platelet aggregation test and the other showed restenosis in DSA). Computed tomography angiography (CTA) of 10 patients and Duplex scan of 7 patients during the follow-up demonstrated carotid in good morphology and fluent blood flow, without kinking or restenosis. Conclusion CAS is a feasible and safe therapeutic method and maybe helpful to lower the risk of cerebral ischemia for the patients with symptomatic kinking and stenosis. However, further study is still needed. [ABSTRACT FROM AUTHOR]