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Objectives: To evaluate the safety and feasibility of the use of covered stents for the treatment of extracranial carotid artery stenosis caused by highly embologenic plaques, and to study the long-term outcome of patients receiving such covered stents.Methods: Between 2002 and 2007, 46 patients (63% symptomatic, 78.3% male, 67 +/- 8.6 years old) with internal carotid artery stenosis caused by embologenic plaques or restenosis were treated with self-expanding covered stents (Symbiot, Boston Scientific). Pre-dilatation or protecting devices were not used. Post-dilatation was applied in every patient. Each patient was followed long-term. The outcome measures were the occurrence of neurological events, and the development of in-stent restenosis, as detected by clinical examination and duplex ultrasound.Results: The technical success rate of stenting was 100%. There were no neurological complications in the peri-procedural period. The mean follow-up period was 34.3 +/- 27.7 months (the rate of patients lost to follow-up was 15.2%) during which no stroke or stroke-related deaths occurred. Restenosis was detected in 3 patients (6.5%).Conclusion: Covered stents provide efficient peri- and post-procedural protection against neurological complications due to embolisation from high-risk plaques during carotid artery stenting. Restenosis of covered stents appears to be infrequent during long-term follow-up. [ABSTRACT FROM AUTHOR]

Background: Amyloid-β-related angiitis (ABRA) is a rare complication of cerebral amyloid angiopathy, characterized by amyloid-β deposition in the leptomeningeal and cortical vessels with associated angiodestructive granulomatous inflammation. The clinical presentation is variable, including subacute cognitive decline, behavioural changes, headaches, seizures and focal neurological deficits, which may mimic other conditions. Here, we present a case with fatal thrombolysis-related haemorrhage associated with ABRA in a middle-aged patient., Case Presentation: A 55-year-old man was admitted to hospital with sudden onset left-sided cheek, arm and hand sensory loss, blurred vision, and worsening headache, with a National Institutes of Health Stroke Scale (NIHSS) score of 3. An acute CT head scan showed no contraindications, and therefore the decision was made to give intravenous thrombolysis. Post-thrombolysis, he showed rapid deterioration with visual disturbances, headache and confusion, and a repeat CT head scan confirmed several areas of intracerebral haemorrhage. No benefit from surgical intervention was expected, and the patient died four days after the first presentation. Neuropathological examination found acute ischemic infarcts of three to five days duration in the basal ganglia, insular cortex and occipital lobe, correlating with the initial clinical symptoms. There were also extensive recent intracerebral haemorrhages most likely secondary to thrombolysis. Furthermore, the histological examination revealed severe cerebral amyloid angiopathy associated with granulomatous inflammatory reaction, consistent with ABRA., Conclusions: Presentation of ABRA in a middle-aged patient highlighted the difficulties in recognition and management of this rare condition. There is emerging evidence that patients with CAA may have increased risk of fatal intracerebral haemorrhages following thrombolysis. This may be further increased by a coexisting CAA-related inflammatory vasculopathy which is potentially treatable with steroid therapy if early diagnosis is made., (© 2022. Crown.)

Recent reports have highlighted rare, and sometimes fatal, cases of cerebral venous sinus thrombosis (CVST) and thrombocytopenia following the Vaxzevria vaccine. An underlying immunological mechanism similar to that of spontaneous heparin-induced thrombocytopenia (HIT) is suspected, with the identification of antibodies to platelet factor-4 (PF4), but without previous heparin exposure. This unusual mechanism has significant implications for the management approach used, which differs from usual treatment of CVST. We describe the cases of two young males, who developed severe thrombocytopenia and fatal CVST following the first dose of Vaxzevria. Both presented with a headache, with subsequent rapid neurological deterioration. One patient underwent PF4 antibody testing, which was positive. A rapid vaccination programme is essential in helping to control the COVID-19 pandemic. Hence, it is vital that such COVID-19 vaccine-associated events, which at this stage appear to be very rare, are viewed through this lens. However, some cases have proved fatal. It is critical that clinicians are alerted to the emergence of such events to facilitate appropriate management. Patients presenting with CVST features and thrombocytopenia post-vaccination should undergo PF4 antibody testing and be managed in a similar fashion to HIT, in particular avoiding heparin and platelet transfusions., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background and Purpose: Diagnosis of coronavirus disease 2019 (COVID-19) relies on clinical features and reverse-transcriptase polymerase chain reaction testing, but the sensitivity is limited. Carotid CTA is a routine acute stroke investigation and includes the lung apices. We evaluated CTA as a potential COVID-19 diagnostic imaging biomarker., Materials and Methods: This was a multicenter, retrospective study ( n  = 225) including CTAs of patients with suspected acute stroke from 3 hyperacute stroke units (March-April 2020). We evaluated the reliability and accuracy of candidate diagnostic imaging biomarkers. Demographics, clinical features, and risk factors for COVID-19 and stroke were analyzed using univariate and multivariate statistics., Results: Apical ground-glass opacification was present in 22.2% (50/225) of patients. Ground-glass opacification had high interrater reliability (Fleiss κ = 0.81; 95% CI, 0.68-0.95) and, compared with reverse-transcriptase polymerase chain reaction, had good diagnostic performance (sensitivity, 75% [95% CI, 56-87]; specificity, 81% [95% CI, 71-88]; OR = 11.65 [95% CI, 4.14-32.78]; P  < .001) on multivariate analysis. In contrast, all other contemporaneous demographic, clinical, and imaging features available at CTA were not diagnostic for COVID-19. The presence of apical ground-glass opacification was an independent predictor of increased 30-day mortality (18.0% versus 5.7%, P  = .017; hazard ratio = 3.51; 95% CI, 1.42-8.66; P  = .006)., Conclusions: We identified a simple, reliable, and accurate COVID-19 diagnostic and prognostic imaging biomarker obtained from CTA lung apices: the presence or absence of ground-glass opacification. Our findings have important implications in the management of patients presenting with suspected stroke through early identification of COVID-19 and the subsequent limitation of disease transmission., (© 2021 by American Journal of Neuroradiology.)

Acute basilar artery occlusion (BAO) is a rare but potentially life-threatening neurological condition. While endovascular therapy (EVT) has been shown to improve outcome, there is limited knowledge about prognostic factors beyond early recanalization. We studied whether blood pressure (BP) exceeds or falls below suggested thresholds during intervention and whether these changes are associated with complications and outcome. BP measurements mostly with one-minute intervals were available in 39 patients. An individual systolic blood pressure (SBP) reference value was defined as the median of the first five intra-procedural measurements. Half of the patients (51.3%) received drugs for BP augmentation and two a BP lowering drug (5.1%). Thrombolysis in cerebral infarction grade 2b and 3 (TICI) was achieved in 29 (74.4%) and 23 patients (58.9%) had good outcome at three months. We observed a continuous intra-procedural increase of median SBP (+11%) and mean arterial pressure (MAP, +10%, both p < 0.001), and a unique temporal pattern of intermittent peaks and troughs. Successful recanalization was more common in patients whose intra-procedural duration with SBP under 140 mmHg was shorter (p = 0.009). Patients with isolated tip of basilar artery (TBA) occlusion had significantly more BP excursion of 20% below the reference SBP and required more frequent use of sympathomimetic drugs compared to vertebrobasilar occlusion (p = 0.008 and p = 0.041, respectively). Brain hemorrhage was more prevalent in patients who experienced SBP excursions at least 20% above the individual reference value (p = 0.038) and a longer duration of time spent with SBP above 180 mmHg (p = 0.029). Patients with higher pre-procedural mean SBP had a greater chance of a good outcome (p = 0.03). This study using high resolution BP monitoring suggests a relationship between intra-procedural BP characteristics and recanalization, hemorrhagic complications and outcome in patients receiving EVT for acute posterior circulation cerebrovascular syndromes. Differences with regard to BP regulation during recanalization therapy for vertebrobasilar and TBA occlusion deserves further attention.

The contribution of lipids, including low- and high-density lipoprotein cholesterol (LDL-C and HDL-C, respectively) and triglycerides (TG), to stroke outcomes is still debated. We sought to determine the impact of LDL-C concentrations on the outcome of patients with ischemic stroke in the anterior circulation who received treatment with endovascular thrombectomy (EVT). We performed a retrospective analysis of consecutive patients with acute ischemic stroke treated at a tertiary center between 2012 and 2016. Patients treated with EVT for large artery occlusion in the anterior circulation were selected. The primary endpoint was functional outcome at 3 months as measured with the modified Rankin Scale (mRS). Secondary outcome measures included hospital death and final infarct volume (FIV). Blood lipid levels were determined in a fasting state, 1 day after admission. We studied a total of 174 patients (44.8% men) with a median age of 74 years (interquartile range [IQR] 61-82) and median National Institutes of Health Stroke Scale at admission of 18 (14-22). Bridging therapy with intravenous tissue-plasminogen activator (t-PA) was administered in 122 (70.5%). The median LDL-C was 90 mg/dl (72-115). LDL-C demonstrated a U-type relationship with FIV (p = 0.036). Eighty-three (50.0%) patients had an mRS of 0-2 at 3 months. This favorable outcome was independently associated with younger age (OR 0.944, 95% CI 0.90-0.99, p = 0.012), thrombolysis in cerebral infarction 2b-3 reperfusion (OR 5.12, 95% CI 1.01-25.80, p = 0.015), smaller FIV (0.97 per cm 3 , 95% CI 0.97-0.99, p < 0.001), good leptomeningeal collaterals (OR 5.29, 95% CI 1.48-18.9, p = 0.011), and LDL-C more than 77 mg/dl (OR 0.179, 95% CI 0.04-0.74, p = 0.018). A higher LDL-C concentration early in the course of a stroke caused by large artery occlusion in the anterior circulation is independently associated with a favorable clinical outcome at 3 months. Further studies into the pathophysiological mechanisms underlying this observation are warranted.

Ischemic stroke related to tandem internal carotid and middle cerebral artery (TIM) occlusion is a challenging condition where endovascular treatment (EVT) is an emerging revascularization option. The identification of factors influencing clinical outcomes can assist in creating appropriate therapeutic algorithms for such patients. This study aimed to evaluate prognostic factors in the context of EVT for TIM occlusion. We performed a retrospective study of consecutive patients with TIM occlusion admitted within 6 h from symptom onset to two tertiary stroke centers. We recorded the etiology of stroke, clinical deficits at stroke onset and discharge, details of EVT, final infarct volume (FIV), in-hospital mortality, and outcome at three months. Among 73 patients with TIM occlusion, 53 were treated with EVT. The median age was 75.9 years (interquartile range (IQR) 64.6⁻82.6), with the most common etiology of cardioembolism (51.9%). Intravenous thrombolysis with tissue-plasminogen activator (t-PA) was performed in the majority (69.8%) of cases. EVT achieved successful recanalization with a thrombolysis in cerebral infarction (TICI) grade of 2b or 3 in 67.9%. A good outcome (modified Rankin score of 0⁻2 at three months) was observed in 37.7%. After adjustment for age, the National Institutes of Health Stroke Scale (NIHSS) at admission, and success of recanalization, smaller final infarct volume (odds ratio (OR) 0.021 for FIV above 25th percentile (95% CI 0.001⁻0.332, p = 0.005)) and administration of intravenous t-PA (OR 12.04 (95% CI 1.004⁻144.392, p = 0.049)) were associated with a good outcome at three months. Our study demonstrates that bridging with t-PA is associated with improved outcomes in the setting of tandem ICA and MCA occlusions treated with EVT and should therefore not be withheld in eligible patients., Competing Interests: The authors declare no conflicts of interest.

Background: Intracerebral hemorrhage and ischemic stroke are increasingly recognized complications of central nervous system (CNS) infection by herpes simplex virus (HSV)., Aim of the Study: To analyze clinical, imaging, and laboratory findings and outcomes of cerebrovascular manifestations of HSV infection., Methods: Systematic literature review from January 2000 to July 2018., Results: We identified 38 patients (median age 45 years, range 1-73) comprising 27 cases of intracerebral hemorrhage, 10 of ischemic stroke, and 1 with cerebral venous sinus thrombosis. Intracerebral hemorrhage was predominantly (89%) a complication of HSV encephalitis located in the temporal lobe. Hematoma was present on the first brain imaging in 32%, and hematoma evacuation was performed in 30% of these cases. Infarction was frequently multifocal, and at times preceded by hemorrhage (20%). Both a stroke-like presentation and presence of HSV encephalitis in a typical location were rare (25% and 10%, respectively). There was evidence of cerebral vasculitis in 63%, which was exclusively located in large-sized vessels. Overall mortality was 21% for hemorrhage and 0% for infarction. HSV-1 was a major cause of hemorrhagic complications, whereas HSV-2 was the most prevalent agent in the ischemic manifestations., Conclusion: We found a distinct pathogenesis, cause, and outcome for HSV-related cerebral hemorrhage and infarction. Vessel disruption within a temporal lobe lesion caused by HSV-1 is the presumed mechanism for hemorrhage, which may potentially have a fatal outcome. Brain ischemia is mostly related to multifocal cerebral large vessel vasculitis associated with HSV-2, where the outcome is more favorable.

Background: The development of intracranial hemorrhage (ICH) in acute ischemic stroke is associated with a higher neutrophil to lymphocyte ratio (NLR) in peripheral blood. Here, we studied whether the predictive value of NLR at admission also translates into the occurrence of hemorrhagic complications and poor functional outcome after endovascular treatment (EVT)., Methods: We performed a retrospective analysis of consecutive patients with anterior circulation ischemic stroke who underwent EVT at a tertiary care center from 2012 to 2016. Follow-up scans were examined for non-procedural ICH and scored according to the Heidelberg Bleeding Classification. Demographic, clinical, and laboratory data were correlated with the occurrence of non-procedural ICH., Results: We identified 187 patients with a median age of 74 years (interquartile range [IQR] 60-81) and a median baseline National Institutes of Health Stroke scale (NIHSS) score of 18 (IQR 13-22). A bridging therapy with recombinant tissue-plasminogen activator (rt-PA) was performed in 133 (71%). Of the 31 patients with non-procedural ICH (16.6%), 13 (41.9%) were symptomatic. Patients with ICH more commonly had a worse outcome at 3 months (p = 0.049), and were characterized by a lower body mass index, more frequent presence of tandem occlusions, higher NLR, larger intracranial thrombus, and prolonged rt-PA and groin puncture times. In a multivariate analysis, higher admission NLR was independently associated with ICH (OR 1.09 per unit increase, 95% CI (1.00-1.20, p = 0.040). The optimal cutoff value of NLR that best distinguished the development of ICH was 3.89., Conclusions: NLR is an independent predictor for the development of ICH after EVT. Further studies are needed to investigate the role of the immune system in hemorrhagic complications following EVT, and confirm the value of NLR as a potential biomarker.

Background and Purpose: Current guidelines do not recommend the use of intravenous recombinant tissue plasminogen activator in patients with acute ischemic stroke who receive direct oral anticoagulants. While the humanized monoclonal antibody idarucizumab can quickly reverse the anticoagulant effects of the thrombin inhibitor dabigatran, safety data for subsequent tissue plasminogen activator treatment are sparse. Here, we review current knowledge about dabigatran reversal prior to systemic reperfusion treatment in acute ischemic stroke., Methods: We performed a systematic review of all published cases of intravenous tissue plasminogen activator treatment following the administration of a dabigatran antidote up to June 2017 and added five unpublished cases of our own. We analyzed clinical and radiological outcomes, symptomatic post-thrombolysis intracranial hemorrhage, and other serious systemic bleeding. Additional endpoints were allergic reaction to idarucizumab, and venous thrombosis in the post-acute phase., Results: We identified a total of 21 patients (71% male) with a median age of 76 years (interquartile range 70-84). The median National Institute of Health Stroke Scale score at baseline was 10 (n = 20, interquartile range 5-11) and 18/20 patients (90%) had mild or moderate stroke severity. The time from symptom onset to start of tissue plasminogen activator was 155 min (n = 18, interquartile range 122-214). The outcome was unfavorable in 3/19 patients (16%). There was one fatality as a result of a symptomatic post-thrombolysis intracranial hemorrhage, and two patients experienced an increase in the National Institute of Health Stroke Scale compared with baseline. One patient had a recurrent stroke. No systemic bleeding, venous thrombosis, or allergic reactions were reported., Conclusion: Experience with idarucizumab administration prior to tissue plasminogen activator treatment in acute ischemic stroke is limited. Initial clinical experience in less severe stroke syndromes and short time windows seems favorable. Larger cohorts are required to confirm safety, including bleeding complications and the risk of thrombosis.

Background: Multimodal CT or MR imaging may be helpful in guiding reperfusion therapy for stroke. However, access to multimodal imaging may frequently be limited. We hypothesised that certain clinical and non-enhanced CT (NECT) findings at initial assessment can potentially predict mismatch on CT perfusion (CTP) in patients with acute ischaemic stroke., Methods: We undertook an analysis of prospectively collected clinical and imaging data of consecutive patients with anterior circulation ischaemic stroke who underwent CTP during their initial assessment. NECT was read for early ischaemic change as measured by the Alberta Stroke Program Early CT Score (ASPECTS), and for hyperdense middle cerebral artery sign (HMCAS). CTP images were evaluated for mismatch. Independent clinical and imaging predictors of a CTP mismatch were identified using stepwise logistic regression., Results: Of the 202 patients, 92 (46%) demonstrated a mismatch, 23 (11%) a matched deficit, and 87 (43%) no perfusion deficit. HMCAS on NECT (OR 13.65, 95% CI 6.04-30.81, p<0.001), female gender (OR 2.37, 95% CI 1.19-4.72, p = 0.015), atrial fibrillation (OR 2.05, 95% CI 1.02-4.11, p = 0.044), and absence of a history of hypertension (OR 0.46, 95% CI 0.22-0.96, p = 0.037) were independent predictors of a CTP mismatch. HMCAS had 58% sensitivity, 91% specificity, 84% positive predictive value and 72% negative predictive value., Conclusions: A HMCAS on the initial NECT is associated with a high probability of mismatch in acute ischaemic stroke, and may identify patients most likely to benefit from recanalisation treatments when access to multimodal CT or MR facilities is limited., (© 2013 Elsevier B.V. All rights reserved.)

Recent meta-analyses have indicated that patients with vascular disease demonstrated by laboratory tests to be aspirin or clopidogrel-resistant are at an increased risk of major vascular events. The suggested mechanisms of aspirin resistance include genetic polymorphism, alternative pathways of platelet activation, aspirin-insensitive thromboxane biosynthesis, drug interactions, or a low aspirin dose. Clopidogrel resistance is likely to develop as a result of a decreased bioavailability of the active metabolite, due to genetic variation or concomitant drug treatment. Additional work is required to improve and validate laboratory tests of platelet function, so that they may become useful tools for selection of the most appropriate antiplatelet therapy for an individual patient. Improvements in antiplatelet treatment strategies in the future should lead to a reduction in premature vascular events.

Aspirin and clopidogrel are well established as antiplatelet medication in the treatment of atherothrombotic vascular disease. However, despite treatment, a substantial number of patients experience recurrent ischemic episodes, referred to as aspirin or clopidogrel treatment failure. Various laboratory techniques are available with which to evaluate the effectiveness of antiplatelet drugs. Interestingly, the agreement between the results of the different tests may be poor. The term aspirin or clopidogrel resistance denotes those conditions in which an inadequate inhibitory efficacy of the given antiplatelet agent is detected by an in vitro assay of platelet function. It has been estimated that on average some 30% of patients treated with aspirin, and 20% on clopidogrel, do not achieve an appropriate level of efficacy as concerns platelet activity.

Objectives and Methods: Genetic predisposition of the inflammatory host response may affect the development of stroke. On the basis of the theory of infectious burden and risk of stroke, we considered it of interest to investigate the relevance of the single-nucleotide polymorphisms (SNPs) in the DEFB1 gene and the copy number variant (CNV) of the DEFB4 genes in ischemic stroke., Results: There were no significant differences in the genotype frequencies of the three SNPs of the DEFB1 gene between the patients with stroke (n = 312) and the healthy blood donors (n = 221). However, a higher frequency of a lower (<4) copy number of the DEFB4 gene was observed in the patients with ischemic stroke as compared with the healthy controls (40% vs 24%, respectively). Additionally, low plasma concentrations of hBD-2 (187 ± 20 pg/ml) were characteristic of the patients with fewer than four copy numbers relative to those with more than four copy numbers (385 ± 35 pg/ml)., Conclusions: The low copy number of the DEFB4 gene, involving a weakened antimicrobial defense of the host, might be important in the pathogenesis of stroke., (© 2011 John Wiley & Sons A/S.)

Objective: It may be possible to thrombolyse ischaemic stroke (IS) patients up to 6 h by using penumbral imaging. We investigated whether a perfusion CT (CTP) mismatch can help to select patients for thrombolysis up to 6 h., Methods: A cohort of 254 thrombolysed IS patients was studied. 174 (69%) were thrombolysed at 0-3 h by using non-contrast CT (NCCT), and 80 (31%) at 3-6 h (35 at 3-4.5 h and 45 at 4.5-6 h) by using CTP mismatch criteria. Symptomatic intracerebral haemorrhage (SICH), the mortality and the modified Rankin Score (mRS) were assessed at 3 months. Independent determinants of outcome in patients thrombolysed between 3 and 6 h were identified., Results: The baseline characteristics were comparable in the two groups. There were no differences in SICH (3% v 4%, p = 0.71), any ICH (7% v 9%, p = 0.61), or mortality (16% v 9%, p = 0.15) or mRS 0-2 at 3 months (55% v 54%, p = 0.96) between patients thrombolysed at 0-3 h (NCCT only) or at 3-6 h (CTP mismatch). There were no significant differences in outcome between patients thrombolysed at 3-4.5 h or 4.5-6 h. The NIHSS score was the only independent determinant of a mRS of 0-2 at 3 months (OR 0.89, 95% CI 0.82-0.97, p = 0.007) in patients treated using CTP mismatch criteria beyond 3 h., Conclusions: The use of a CTP mismatch model may help to guide thrombolysis decisions up to 6 h after IS onset.

The European Association of Young Neurologists and Trainees (EAYNT) is a non-profit organization which acts on behalf of young neurologists in Europe and concertedly exerts influence on the formation of a new generation of neurologists [Struhal et al.: Eur J Neurol 2009;16:e146-e148]. This concerns particularly the Generation Y (Gen Y), also known as Millennial Generation, Digital Natives or Generation Next, a demographic cohort defined by birth between 1981 and 1999 [Elkind: Neurology 2009;72:657-663]. A unifying feature is the increased use and familiarity with online media and digital technologies. Online social networks and interactive communication have not only shaped this cohort but necessitate a different approach towards educational matters. This position paper aims to address the changing needs for Gen Yers in the context of education., (Copyright © 2011 S. Karger AG, Basel.)

Background and Purpose: Chronic infections with certain pathogens, such as Chlamydia pneumoniae, and genetic parameters that influence inflammatory reactions have been suggested to contribute to ischaemic stroke. NOD1 is a potent cytosolic receptor for C. pneumoniae. The aim of this study was to investigate the genetic polymorphism of NOD1 from the aspect of the development of stroke., Materials and Methods: A total of 280 patients with ischaemic stroke were enrolled in the study; 150 healthy blood donors served as controls. The G796A (E266K) NOD1 polymorphism was determined by restriction fragment length polymorphism. Chlamydia pneumoniae seropositivity was tested by ELISA., Results: There was a significant difference in NOD1 G796A genotype distribution between the controls and the stroke patients with C. pneumoniae seropositivity. The AA homozygote and GA heterozygote mutant variants were detected in 16% (25 of 152) and in 50% (77 of 152) of the C. pneumoniae-positive stroke patients, as compared with 8% (6 of 84), and 28% (24 of 84), respectively, in the C. pneumoniae-positive healthy controls. (OR = 2.559; 95% CI = 1.105-6.517, P = 0.04 and OR = 2.567; 95% CI = 1.451-4.540 P < 0.001, respectively). The stroke patients with the large vessel pathology exhibited the highest frequency of the mutant allele A (51%). In contrast, amongst the C. pneumoniae-negative subjects, no difference in genotype frequency was observed between the stroke patients and the controls., Conclusion: Polymorphism in NOD1 G796A alone did not prove to be a risk factor for stroke in general, but in association with C. pneumoniae infection it appeared to be accompanied by an increased risk of the development of stroke.

While stroke is a known cause of a cognitive impairment, the relationship between a carotid artery stenosis and the cognitive function in individuals without a history of stroke is less clear. A number of risk factors for vascular disease are related to a cognitive impairment. Hypertension, diabetes mellitus, cigarette smoking, and dyslipidemia are also associated with an increased risk of carotid artery disease. Some studies have suggested that a stenosis of the internal carotid artery may be an independent risk factor for a cognitive impairment. A high-grade stenosis of the internal carotid artery may be associated with a cognitive impairment even without evidence of infarction on magnetic resonance imaging. On the other hand, it is fairly common that patients display a normal cognition despite severe carotid artery disease, highlighting the important role of an efficient collateral blood supply. The possible pathomechanisms of a cognitive impairment include silent embolization and hypoperfusion. Carotid endarterectomy or stenting may lead to a decline in the cognitive function in consequence of microembolic ischemia or intraprocedural hypoperfusion. Conversely, perfusion restoration could improve a cognitive dysfunction that might have occurred from a state of chronic hypoperfusion. It is unclear whether these complex interactions ultimately result in a net improvement or a deterioration of the cognitive function. The evidence available at present does not seem strong enough to include consideration of a loss of cognition as a factor in determining the balance of the risks and benefits of therapy for a carotid stenosis.

Background and Purpose: Large multicenter trials have already evaluated the relative benefit of various types of antithrombotic medication in ischemic stroke. However, the application of the trial results still remains uncertain in some clinical situations. We set out to evaluate the various aspects of antithrombotic treatment use among clinical practitioners., Methods: A virtually nationwide survey was performed among Hungarian neurologists involved in stroke care, who responded to a questionnaire concerning the use of antiplatelet agents and anticoagulation in acute ischemic stroke and for secondary prevention., Results: The response rate was 65%. Most (69%) practitioners always wait for brain imaging before initiating antithrombotic treatment in acute stroke. Aspirin (100 mg/day) is the most frequently prescribed antiplatelet agent after a first ischemic episode. Common reasons for the prescription of alternative agents instead of aspirin after a first attack include high-risk cases and intolerance or allergy to aspirin. The results of in vitro platelet aggregation studies frequently influence drug selection. If an event recurs during a given antiplatelet treatment, most neurologists change the medication. Some participants reported the administration of anticoagulation, or of the combination of aspirin plus clopidogrel in certain situations that are not cardiological indications., Conclusions: This study provides information on the use of antithrombotic treatment in general neurological practice, including everyday clinical situations where no help is available from guidelines.

Objectives: To investigate whether the results of optical platelet aggregometry indicate the risk of recurrent ischemic events., Materials and Methods: Cerebro- and cardiovascular patients taking aspirin for at least 30 days were studied retrospectively. Ischemic vascular events occurring prior to testing and the presence of vascular risk factors were recorded., Results: 241 subjects were included. Among the 78 patients (32.4%) who displayed recurrent vascular episodes, the age (62.5 +/- 10.6 vs. 58.4 +/- 11.6, P = 0.009) and the proportion of hypertensives (80.8% vs. 68.1%, P = 0.040) were significantly higher when compared with the participants who exhibited single events. The degree of platelet aggregation did not differ significantly between the patients with and those without recurrent episodes. Logistic regression analysis identified only age (OR 1.033, 95% CI 1.008-1.058, P = 0.010), and not aggregation values, as a risk condition for recurrent vascular episodes., Conclusions: Results of optical platelet aggregometry were not indicative of the risk of recurrent vascular events. The role of conventional risk factors appeared to be more important.

Aspirin is a well-established medication in the treatment of atherothrombotic vascular disease. However, despite aspirin treatment a substantial number of patients experience recurring ischaemic episodes. Aspirin resistance denotes those situations when it is unable to protect individuals from thrombotic complications, or when it fails to produce an anticipated effect in laboratory tests of platelet function. There are various laboratory techniques with which to evaluate the effectiveness of aspirin and other antiplatelet drugs. It has been estimated that in 5-60% of patients, aspirin does not achieve adequate efficacy in various measures of platelet activity. Some studies have revealed that vascular patients shown by laboratory tests to be aspirin-resistant are at an increased risk of major vascular events. The suggested mechanisms of aspirin resistance, among others, include genetic polymorphisms, alternate pathways of platelet activation, aspirin-insensitive thromboxane biosynthesis, drug interactions, or low aspirin dose. An increase in the dosage of aspirin or conversion to clopidogrel or clopidogrel plus aspirin might be beneficial in the management of those patients who are aspirin resistant. Additional work is required to improve and validate laboratory tests of platelet function, so that they may become useful tools for selecting the most appropriate antiplatelet therapy for an individual patient. Improvements in antiplatelet treatment strategies in the future should lead to a reduction in premature vascular events.

Background and Purpose: Protection devices are increasingly used in carotid artery stenting. However, no randomized trial has been conducted to evaluate the efficacy of such devices, and arguments have also been formulated against their routine use. We set out to investigate the complication rates associated with carotid artery stenting performed without protection devices. Applicability of covered stents in the carotid system was also evaluated., Methods: Between January 2001 and July 2003, 245 consecutive patients (260 hemispheres) underwent carotid artery stenting. No protection devices were applied. Covered stents were implanted in 31 (12.1%) cases. The incidence of complications during the intervention and the subsequent 30-day follow-up period was recorded., Results: The technical success rate was 98.8%. One postprocedural nonneurological death (0.4%) occurred. Neurological complications (inclusive of transient ischemic attacks) were observed in 14 cases (5.4%). The rate of major complications (death, major stroke, and myocardial infarction) was 1.6% among the symptomatic and 1.5% among the asymptomatic cases. The rate of minor strokes was 3.2% in the symptomatic and 1.5% in the asymptomatic group. Of the neurological complications, 64.3% occurred postprocedurally. No ipsilateral neurological complications were detected in the subgroup treated with covered stents., Conclusions: Carotid artery stenting without protection devices appears to be safe. Most of the neurological complications could not have been prevented with protection devices, because they occurred after the intervention. The application of covered stents may reduce the rate of embolization-related complications in the periprocedural period.