Pro-inflammatory cytokine network in peripheral inflammation response to cerebral ischemia

The key circulating pro-inflammatory cytokines and their interaction in peripheral inflammation after acute cerebral ischemia are poorly understood. CD40L, IFN-γ, IL-1α, IL-1β, IL-6, IL-8, IL-17 and TNF-α were determined using multi-ELISA kit in stroke patients within 72 h of an acute ischemic attack. Leukocyte mRNAs were determined using real-time polymerase chain reactions (PCR). Stroke severity and clinical outcomes were evaluated by National Institutes of Health Stroke Scores (NIHSS) and modified Rankin Scale (mRS). Plasma/mRNA cytokine interactions were analyzed using the Bayesian network learning procedure. Compared to controls, stroke patients had higher IL-6, IL-8 and TNFα protein in plasma and lower IL-6, IL-8, TNFα, IL-1α, and IL-1β mRNA in leukocyte within 72 h after stroke. However, only the elevation of IL-6 correlated with the severity and prognosis of their stroke. This was associated with a decreased IL-6 mRNA in leukocyte. Further study showed that Bayesian network analysis revealed that changes in the other cytokines were subsequent to IL-6 leukocyte cytokine RNA. The change of other cytokines in plasma proteins after ischemic brain injury appeared secondary to IL-6. Pro-inflammatory cytokines up-regulation in plasma and compensatory immunity depression in leukocyte involve in peripheral inflammation response to cerebral ischemia. IL-6 appears to be the key mediator of circulating pro-inflammatory cytokines network.

Rarer in a rare

Though moya moya disease is a disease of Asian origin, it is one of the very rare causes of stroke in India. It is a rare disease mainly characterized by progressive cerebrovascular episode due to the slowly progressive stenosis of supraclinoid segment of bilateral internal carotid arteries, the anterior and the middle cerebral arteries, and very rarely, posterior cerebral arteries. We hereby report a case of a young female who presented to us with the psychiatric complaints and refractory headache since her childhood. Therefore, we are reporting rarer (headache and neuropsychiatric) manifestations in the rare (moya moya) disease.

Changes in hemodynamic responses in chronic stroke survivors do not affect fMRI signal detection in a block experimental design

The use of canonical functions to model BOLD-fMRI data in people post-stroke may lead to inaccurate descriptions of task-related brain activity. The purpose of this study was to determine whether the spatiotemporal profile of hemodynamic responses (HDRs) obtained from stroke survivors during an event-related experiment could be used to develop individualized HDR functions that would enhance BOLD-fMRI signal detection in block experiments. Our long term goal was to use this information to develop individualized HDR functions for stroke survivors that could be used to analyze brain activity associated with locomotor-like movements. We also aimed to examine the reproducibility of HDRs obtained across two scan sessions in order to determine whether data from a single event-related session could be used to analyze block data obtained in subsequent sessions. Results indicate that the spatiotemporal profile of HDRs measured with BOLD-fMRI in stroke survivors was not the same as that observed in individuals without stroke. We observed small between-group differences in the rates of rise and decline of HDRs that were more apparent in individuals with cortical as compared to subcortical stroke. There were no differences in the peak or time to peak of HDRs in people with and without stroke. Of interest, differences in HDRs were not as substantial as expected from previous reports and were not large enough to necessitate the use of individualized HDR functions to obtain valid measures of movement-related brain activity. We conclude that all strokes do not affect the spatiotemporal characteristics of HDRs in such a way as to produce inaccurate representations of brain activity as measured by BOLD-fMRI. However, care should be taken to identify individuals whose BOLD-fMRI data may not provide an accurate representation of underlying brain activation when canonical models are used. Examination of HDRs need not be done for each scan session, as our data suggest that the characteristics of HDRs in stroke survivors are reproducible across days.

Neuroprotective effect of agmatine in rats with transient cerebral ischemia using MR imaging and histopathologic evaluation

PURPOSE

This study aimed to further investigate the effects of agmatine on brain edema in the rats with middle cerebral artery occlusion (MCAO) injury using magnetic resonance imaging (MRI) monitoring and biochemical and histopathologic evaluation.

MATERIALS AND METHODS

Following surgical induction of MCAO for 90min, agmatine was injected 5min after beginning of reperfusion and again once daily for the next 3 post-operative days. The events during ischemia and reperfusion were investigated by T2-weighted images (T2WI), serial diffusion-weighted images (DWI), calculated apparent diffusion coefficient (ADC) maps and contrast-enhanced T1-weighted images (CE-T1WI) during 3h-72h in a 1.5T Siemens MAGNETON Avanto Scanner. Lesion volumes were analyzed in a blinded and randomized manner. Triphenyltetrazolium chloride (TTC), Nissl, and Evans Blue stainings were performed at the corresponding sections.

RESULTS

Increased lesion volumes derived from T2WI, DWI, ADC, CE-T1WI, and TTC all were noted at 3h and peaked at 24h-48h after MCAO injury. TTC-derived infarct volumes were not significantly different from the T2WI, DWI-, and CE-T1WI-derived lesion volumes at the last imaging time (72h) point except for significantly smaller ADC lesions in the MCAO model (P<0.05). Volumetric calculation based on TTC-derived infarct also correlated significantly stronger to volumetric calculation based on last imaging time point derived on T2WI, DWI or CE-T1WI than ADC (P<0.05). At the last imaging time point, a significant increase in Evans Blue extravasation and a significant decrease in Nissl-positive cells numbers were noted in the vehicle-treated MCAO injured animals. The lesion volumes derived from T2WI, DWI, CE-T1WI, and Evans blue extravasation as well as the reduced numbers of Nissl-positive cells were all significantly attenuated in the agmatine-treated rats compared with the control ischemia rats (P<0.05).

CONCLUSION

Our results suggest that agmatine has neuroprotective effects against brain edema on a reperfusion model after transient cerebral ischemia.

Apraxia of speech in healthy 36-year-old man

A 36-year-old healthy man presented with sudden onset speech difficulty. Thorough clinical examination revealed interesting deficits suggestive of apraxia of speech. He was found to have an infarct in his frontal region explaining the deficits. We have undertaken clinical evaluation and differential diagnoses of this condition.

Implementing clinical guidelines in stroke: a qualitative study of perceived facilitators and barriers

BACKGROUND

Clinical guidelines are frequently used as a mechanism for implementing evidence-based practice. However research indicates that health professionals vary in the extent to which they adhere to these guidelines. This study aimed to study the perceptions of stakeholders and health professionals on the facilitators and barriers to implementing national stroke guidelines in Ireland.

METHODS

Qualitative interviews using focus groups were conducted with stakeholders (n=3) and multidisciplinary team members from hospitals involved in stroke care (n=7). All focus group interviews were semi-structured, using open-ended questions. Data was managed and analysed using NVivo 9 software.

RESULTS

The main themes to emerge from the focus groups with stakeholders and hospital multidisciplinary teams were very similar in terms of topics discussed. These were resources, national stroke guidelines as a tool for change, characteristics of national stroke guidelines, advocacy at local level and community stroke care challenges. Facilitators perceived by stakeholders and health professionals included having dedicated resources, user-friendly guidelines relevant at local level and having supportive advocates on the ground. Barriers were inadequate resources, poor guideline characteristics and insufficient training and education.

CONCLUSIONS

This study highlights health professionals' perspectives regarding many key concepts which may affect the implementation of stroke care guidelines. The introduction of stroke clinical guidelines at a national level is not sufficient to improve health care quality as they should be incorporated in a quality assurance cycle with education programmes and feedback from surveys of clinical practice.

Intravenous rt-PA in patients with ischaemic stroke and renal dysfunction

OBJECTIVE

Renal dysfunction (RD) increases risk for ischaemic stroke (IS). The impact of RD on the effects of iv-thrombolysis in the Caucasian population has not been fully determined.

AIMS

To evaluate the associations between RD and the outcome of iv-thrombolysis in Caucasian patients with IS.

METHODS

The observational, multicentre study included 404 patients with IS who were treated with iv-thrombolysis. RD was defined as estimated glomerular filtration rate ≤ 60 ml/min/1.73 m(2). Outcome was assessed with modified Rankin Score at 3 months after the stroke onset.

RESULTS

Medians baseline NIHSS score did not differ between groups of patients with and without RD (12.0 vs. 11.0 pts, p=0.33). Unfavourable outcome was found in 52.1% of patients with and in 41.2% of patients without RD (p=0.05), mortality was higher in patients with RD (29.9% vs. 14.3%, p<0.001), and the presence of haemorrhagic transformation (HT) did not differ between the groups (17.1% vs. 17.1% respectively, p=0.996). A multivariate analysis showed no impact of RD on the unfavourable outcome (OR 0.98; 95%CI 0.88-1.10), mortality (OR 0.92; 95%CI 0.81-1.05) or presence of HT (OR 1.03; 95%CI 0.90-1.18).

CONCLUSIONS

We found no impact of RD on the safety and efficacy of iv-thrombolysis in Caucasian patients with IS.

The effect of a hand-stretching device during the management of spasticity in chronic hemiparetic stroke patients

Objective

To describe a hand-stretching device that was developed for the management of hand spasticity in chronic hemiparetic stroke patients, and the effects of this device on hand spasticity.

Methods

Fifteen chronic hemiparetic stroke patients with finger flexor spasticity were recruited and randomly assigned to an intervention group (8 patients) or a control group (7 patients). The stretching device consists of a resting hand splint, a finger and thumb stretcher, and a frame. In use, the stretched state was maintained for 10 minutes per exercise session, and the exercise was performed twice daily for 4 weeks. Spasticity of finger flexor muscles in the two groups was assessed 3 times, 4 weeks apart, using the Modified Ashworth Scale (MAS). Patients in the intervention group were assessed twice (pre-1 and pre-2) before and once (post-1) after starting the stretching program.

Results

Mean MAS (mMAS) scores at initial evaluations were not significantly different at pre-1 in the intervention group and at 1st assessment in the control group (p>0.05). In addition, no significant differences were observed between mMAS scores at pre-1 and pre-2 in the intervention group (p>0.05). However, mMAS scores at post-1 were significantly lower than that at pre-2 in the intervention group (p<0.05). Within the control group, no significant changes in mMAS scores were observed between 1st, 2nd, and 3rd assessments (p>0.05). In addition, mMAS scores at post-1 in the intervention group were significantly decreased compared with those at the 3rd assessment in the control group (p<0.05).

Conclusion

The devised stretching device was found to relieve hand spasticity effectively in chronic hemiparetic stroke patients.

The sitting-unsupported balance score as an early predictor of functional prognosis in stroke patients: a pilot study

OBJECTIVE

To evaluate the impact of initial "sitting-unsupported" Berg Balance Scale (SUB), the specific trunk control parameter, on patients' functional outcome, Korean version of Modified Barthel Index (K-MBI) at 6 months.

METHODS

The charts of 30 patients retrospectively reviewed reviewed. The initial Korean version of Berg Balance Scale (K-BBS) including SUB along with patients' Korean version of Mini-Mental State Examination (K-MMSE), Glasgow Coma Scale (GCS), and other functional parameters that affect functional outcome were recorded. Cases were divided into low (group I) and high (group II) initial SUB score groups. Correlation and regression analysis were performed to assess the relationship between the initial SUB on the K-MBI at 6 months.

RESULTS

The mean±standard deviation score of initial SUB/K-MBI at 6 months of groups I and II were 0.056±0.236/26.89±32.48, 3.58±0.515/80.25±18.78, respectively, and showed statistical significant differences to each other (p<0.05). K-MBI at 6 months was highly correlated with initial GCS, SUB, K-BBS, K-MMSE, and initial K-MBI (p<0.05). In multiple linear regression analysis, initial SUB and GCS scores remained significantly associated with K-MBI at 6 months. A logistic regression model revealed that initial SUB (p=0.004, odds ratio=16), initial K-MBI, GCS, and K-MMSE were all significant predictors of K-MBI scores at 6 months.

CONCLUSION

Initial SUB scores could be helpful in predicting patient's potential functional recovery at 6 months. Further studies with concurrent controls and a larger sample group are required to fully establish this tool.

A multicentre Spanish study for multivariate prediction of perioperative in-hospital cerebrovascular accident after coronary bypass surgery: the PACK2 score

OBJECTIVES

To develop a multivariate predictive risk score of perioperative in-hospital stroke after coronary artery bypass grafting (CABG) surgery.

METHOD

A total of 26 347 patients were enrolled from 21 Spanish hospital databases. Logistic regression analysis was used to predict the risk of perioperative stroke (ictus or transient ischaemic attack). The predictive scale was developed from a training set of data and validated by an independent test set, both selected randomly. The assessment of the accuracy of prediction was related to the area under the ROC curve. The variables considered were: preoperative (age, gender, diabetes mellitus, arterial hypertension, previous stroke, cardiac failure and/or left ventricular ejection fraction<40%, non-elective priority of surgery, extracardiac arteriopathy, chronic kidney failure and/or creatininemia≥2 mg/dl and atrial fibrillation) and intraoperative (on/off-pump).

RESULTS

Global perioperative stroke incidence was 1.38%. Non-elective priority of surgery (priority; OR=2.32), vascular disease (arteriopathy; OR=1.37), cardiac failure (cardiac; OR=3.64) and chronic kidney failure (kidney; OR=6.78) were found to be independent risk factors for perioperative stroke in uni- and multivariate models in the training set of data; P<0.0001; AUC=0.77, 95% CI 0.73-0.82. The PACK2 stroke CABG score was established with 1 point for each item, except for chronic kidney failure with 2 points (range 0-5 points); AUC=0.76, 95% CI 0.72-0.80. In patients with PACK2 score≥2 points, off-pump reduced perioperative stoke incidence by 2.3% when compared with on-pump CABG.

CONCLUSIONS

PACK2 risk scale shows good predictive accuracy in the data analysed and could be useful in clinical practice for decision making and patient selection.

Initial clinical experience with the ADAPT technique: a direct aspiration first pass technique for stroke thrombectomy

BACKGROUND

The development of new revascularization devices has improved recanalization rates and time but not clinical outcomes. We report our initial results with a new technique utilizing a direct aspiration first pass technique with a large bore aspiration catheter as the primary method for vessel recanalization.

METHODS

A retrospective evaluation of a prospectively captured database of 37 patients at six institutions was performed on patients where the ADAPT technique was utilized. The data represent the initial experience with this technique.

RESULTS

The ADAPT technique alone was successful in 28 of 37 (75%) cases although six cases had large downstream emboli that required additional aspiration. Nine cases required the additional use of a stent retriever and one case required the addition of a Penumbra aspiration separator to achieve recanalization. The average time from groin puncture to at least Thrombolysis in Cerebral Ischemia (TICI) 2b recanalization was 28.1 min, and all cases were successfully revascularized. TICI 3 recanalization was achieved 65% of the time. On average, patients presented with an admitting National Institutes of Health Stroke Scale (NIHSS) score of 16.3 and improved to an NIHSS score of 4.2 by the time of hospital discharge. There was one procedural complication.

DISCUSSION

This initial experience highlights the fact that the importance of the technique with which new stroke thrombectomy devices are used may be as crucial as the device itself. The ADAPT technique is a simple and effective approach to acute ischemic stroke thrombectomy. Utilizing the latest generation of large bore aspiration catheters in this fashion has allowed us to achieve excellent clinical and angiographic outcomes.

EHRA practical guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation: executive summary

New oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with non-valvular atrial fibrillation (AF). Both physicians and patients will have to learn how to use these drugs effectively and safely in specific clinical situations. This text is an executive summary of a practical guide that the European Heart Rhythm Association (EHRA) has assembled to help physicians in the use of the different NOACs. The full text is being published in EP Europace. Practical answers have been formulated for 15 concrete clinical scenarios: (i) practical start-up and follow-up scheme for patients on NOACs; (ii) how to measure the anticoagulant effect of NOACs; (iii) drug-drug interactions and pharmacokinetics of NOACs; (iv) switching between anticoagulant regimens; (v) ensuring compliance of NOAC intake; (vi) how to deal with dosing errors; (vii) patients with chronic kidney disease; (viii) what to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a risk of bleeding?; (ix) management of bleeding complications; (x) patients undergoing a planned surgical intervention or ablation; (xi) patients undergoing an urgent surgical intervention; (xii) patients with AF and coronary artery disease; (xiii) cardioversion in a NOAC-treated patient; (xiv) patients presenting with acute stroke while on NOACs; (xv) NOACs vs. VKAs in AF patients with a malignancy. Since new information is becoming available at a rapid pace, an EHRA web site with the latest updated information accompanies the guide (www.NOACforAF.eu). It also contains links to the ESC AF Guidelines, a key message pocket booklet, print-ready files for a proposed universal NOAC anticoagulation card, and feedback possibilities.

High sodium:potassium intake ratio increases the risk for all-cause mortality: the REasons for Geographic And Racial Differences in Stroke (REGARDS) study

Increased dietary Na intake and decreased dietary K intake are associated with higher blood pressure. It is not known whether the dietary Na:K ratio is associated with all-cause mortality or stroke incidence and whether this relationship varies according to race. Between 2003 and 2007, the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort enrolled 30 239 black and white Americans aged 45 years or older. Diet was assessed using the Block 98 FFQ and was available on 21 374 participants. The Na:K ratio was modelled in race- and sex-specific quintiles for all analyses, with the lowest quintile (Q1) as the reference group. Data on other covariates were collected using both an in-home assessment and telephone interviews. We identified 1779 deaths and 363 strokes over a mean of 4·9 years. We used Cox proportional hazards models to obtain multivariable-adjusted hazard ratios (HR). In the highest quintile (Q5), a high Na:K ratio was associated with all-cause mortality (Q5 v. Q1 for whites: HR 1·22; 95 % CI 1·00, 1·47, P for trend = 0·084; for blacks: HR 1·36; 95 % CI 1·04, 1·77, P for trend = 0·028). A high Na:K ratio was not significantly associated with stroke in whites (HR 1·29; 95 % CI 0·88, 1·90) or blacks (HR 1·39; 95 % CI 0·78, 2·48), partly because of the low number of stroke events. In the REGARDS study, a high Na:K ratio was associated with all-cause mortality and there was a suggestive association between the Na:K ratio and stroke. These data support the policies targeted at reduction of Na from the food supply and recommendations to increase K intake.

Evaluation of white matter myelin water fraction in chronic stroke

Multi-component T2 relaxation imaging (MCRI) provides specific in vivo measurement of myelin water content and tissue water environments through myelin water fraction (MWF), intra/extra-cellular water fraction (I/EWF) and intra/extracellular and global geometric mean T2 (GMT2) times. Quantitative MCRI assessment of tissue water environments has provided new insights into the progression and underlying white matter pathology in neural disorders such as multiple sclerosis. It has not previously been applied to investigate changes in white matter in the stroke-affected brain. Thus, the purposes of this study were to 1) use MCRI to index myelin water content and tissue water environments in the brain after stroke 2) evaluate relationships between MWF and diffusion behavior indexed by diffusion tensor imaging-based metrics and 3) examine the relationship between white matter status (MWF and fractional anisotropy) and motor behavior in the chronic phase of stroke recovery. Twenty individuals with ischemic stroke and 12 matched healthy controls participated. Excellent to good test/re-test and inter-rater reliability was observed for region of interest-based voxelwise MWF data. Reduced MWF was observed in whole-cerebrum white matter (p < 0.001) and in the ipsilesional (p = 0.017) and contralesional (p = 0.037) posterior limb of internal capsule (PLIC) after stroke compared to whole-cerebrum and bilateral PLIC MWF in healthy controls. The stroke group also demonstrated increased I/EWF, I/E GMT2 and global GMT2 times for whole-cerebrum white matter. Measures of diffusion behavior were also significantly different in the stroke group across each region investigated (p < 0.001). MWF was not significantly correlated with specific tensor-based measures of diffusion in the PLIC for either group. Fractional anisotropy in the ipsilesional PLIC correlated with motor behavior in chronic stroke. These results provide novel insights into tissue-specific changes within white matter after stroke that may have important applications for the understanding of the neuropathology of stroke.

Vascular endothelial growth factor-B expression in postischemic rat brain

Background

Vascular endothelial growth factor-B (VEGF-B) protects against experimental stroke, but the effect of stroke on VEGF-B expression is uncertain.

Methods

We examined VEGF-B expression by immunohistochemistry in the ischemic border zone 1–7 days after middle cerebral artery occlusion in rats.

Results

VEGF-B immunoreactivity in the border zone was increased after middle cerebral artery occlusion and was associated with neurons and macrophages/microglia, but not astrocytes or endothelial cells.

Conclusions

These findings provide additional evidence for a role of VEGF-B in the endogenous response to cerebral ischemia.

Excellent rates of recanalization and good functional outcome after stent-based thrombectomy for acute middle cerebral artery occlusion. Is it time for a paradigm shift?

The natural history of untreated acute middle cerebral artery (MCA) occlusion is poor, with high rates of mortality (5-33%) and severe long-term disability (40-80% of survivors), despite therapy with intravenous tissue plasminogen activator. We analyzed outcomes in 31 consecutive patients with major ischemic stroke due to acute proximal MCA occlusion who were treated at the Hadassah-Hebrew University Medical Center from February 2010 to October 2012 by endovascular means, using the Solitaire stent (Covidien, Irvine, CA, USA) as a thrombectomy device. Patients had a mean age of 63.3±16.2 years (range, 26-92). The admission National Institutes of Health Stroke Scale score was 19.5±4.3 (median 20). Mean time from symptom onset to femoral artery puncture was 3.8±1.1 hours (median 4 hours). Mean time to recanalization was 46.9±11.1 minutes. Successful recanalization by means of stent-based thrombectomy alone was achieved in 90% of cases and reached 100% after combining definitive stent implantation in three patients. There was no arterial rupture or subarachnoid hemorrhage. Hemorrhagic transformation developed in seven patients (23%), but was symptomatic in only one. Post-procedure CT scan or MRI demonstrated >90% sparing of cortex at risk in all patients. Functional outcome at 90 day follow-up was modified Rankin Score 0-2 in 77% of all patients and 88% of patients younger than 80 years. Three patients (10%) died during hospitalization due to mesenteric event, sepsis, or pulmonary embolism. Our experience suggests that stent-based thrombectomy in selected patients for acute MCA occlusions is safe, very effective in terms of arterial recanalization, and associated with improved neurological outcome. If validated by other groups, endovascular treatment may be proposed as the therapy of choice for MCA occlusion.

Outcomes of apixaban vs. warfarin by type and duration of atrial fibrillation: results from the ARISTOTLE trial

AIMS

It is uncertain whether the benefit from apixaban varies by type and duration of atrial fibrillation (AF).

METHODS AND RESULTS

A total of 18 201 patients with AF [2786 (15.3%) with paroxysmal and 15 412 (84.7%) with persistent or permanent] were randomized to apixaban or warfarin. In this pre-specified secondary analysis, we compared outcomes and treatment effect of apixaban vs. warfarin by AF type and duration. The primary efficacy endpoint was a composite of ischaemic or haemorrhagic stroke or systemic embolism. The secondary efficacy endpoint was all-cause mortality. There was a consistent reduction in stroke or systemic embolism (P for interaction = 0.71), all-cause mortality (P for interaction = 0.75), and major bleeding (P for interaction = 0.50) with apixaban compared with warfarin for both AF types. Apixaban was superior to warfarin in all studied endpoints, regardless of AF duration at study entry (P for all interactions >0.13). The rate of stroke or systemic embolism was significantly higher in patients with persistent or permanent AF than patients with paroxysmal AF (1.52 vs. 0.98%; P = 0.003, adjusted P = 0.015). There was also a trend towards higher mortality in patients with persistent or permanent AF (3.90 vs. 2.81%; P = 0.0002, adjusted P = 0.066).

CONCLUSION

The risks of stroke, mortality, and major bleeding were lower with apixaban than warfarin regardless of AF type and duration. Although the risk of stroke or systemic embolism was lower in paroxysmal than persistent or permanent AF, apixaban is an attractive alternative to warfarin in patients with AF and at least one other risk factor for stroke, regardless of the type or duration of AF.

Isolated hand paresis: a case series

BACKGROUND

Hand knob infarction is a well-known stroke entity. Based on very limited data, embolic stroke mechanism has been considered the most frequent cause; however, prognosis is considered good. We wanted to shed more light on this phenomenon by assessing a cohort of patients referred to a general hospital stroke unit.

METHODS

Every subject admitted to our stroke unit with an acute isolated hand paresis in the period from 2007 to 2012 was identified prospectively. Patients who had suffered from a stroke in the hand motor cortex or an adjacent area explaining the acute loss of hand function were included in the study. The Trial of Org 10172 in Acute Stroke Treatment criteria were used to classify subtypes of stroke according to etiology. The patients were followed up during autumn 2012.

RESULTS

Seventeen subjects were admitted, but in 2 of them symptoms were transitory and magnetic resonance imaging was negative. Two patients were excluded due to persisting sensory deficits. The remaining 13 (11 males and 2 females) patients with an average age of 62.9 (± 13.4) years were included, representing 1.5% of all ischemic strokes diagnosed at the stroke unit in the given period. All patients were right-handed, and the dominant hand was affected only in 4 (31%). The average Medical Research Council's scale score was 3.1 (± 1.4) on admission, and classified as bad. On follow-up, which occurred on average 29.8 (± 19.8) months after the stroke, the score was 4.6 (± 0.4) and was classified as fair to good. No patient experienced a new stroke. The outcome was good to excellent in 10 patients (77%). Two patients died (15%), 1 of probable cardiac arrest and 1 of unknown cause. One patient did not participate in the follow-up. The majority of patients had evidence of both small artery (77%) and large artery (85%) disease. On average, there were 1.6 (± 0.4) new ischemic lesions per patient. Six patients had a solitary lesion (46%). In 5 of them, small artery occlusion was considered the probable stroke mechanism. In 4 cases, the stroke was of undetermined etiology. Three patients had atrial fibrillation, and in 2 of them cardioembolism was the probable stroke mechanism. Two patients with definite large artery atherosclerosis underwent carotid endarterectomy, and 1 of them had comorbid atrial fibrillation.

CONCLUSION

Strokes causing isolated hand paresis seem to have a heterogeneous etiology. Prognosis regarding hand function is good, but long-term outcome depends on stroke etiology and secondary prophylaxis.

Effectiveness of motor imagery or mental practice in functional recovery after stroke: a systematic review

INTRODUCTION

In recent decades, many stroke rehabilitation methods have been developed. Mental practice (MP) is a dynamic state in which the subject evokes an imaginary representation of a motor action or skill in order to learn or perfect that action. Although functional imaging has shown that MP produces similar cortical activation patterns to those of movement, the clinical effectiveness of such methods in rehabilitation and functional recovery has yet to be demonstrated.

DEVELOPMENT

Systematic search of all clinical studies published in the main scientific databases between December 2011 and October 2012 concerning mental practice in stroke rehabilitation. We selected 23 clinical trials testing different MP protocols in patients with hemiparesis.

CONCLUSIONS

MP is effective when used in conjunction with conventional physical therapy for functional rehabilitation of both upper and lower limbs, as well as for the recovery of daily activities and skills. Owing to the heterogeneity of the studies with regard to the intervention protocol, specific imagery technique, time spent practicing, patient characteristics, etc., more studies are needed in order to determine the optimal treatment protocol and patient profile.

Transient ischameic attack/stroke electronic decision support: a 14-month safety audit

BACKGROUND

To assess the safety of a Transient Ischameic Attack (TIA)/Stroke Electronic Decision Support (EDS) tool in the primary care setting intended to aid general practitioners in the timely management of transient ischemic attacks (TIAs).

METHODS

A 14-month safety audit reviewing all patients managed with the help of the TIA/Stroke EDS tool. Major morbidity and mortality were assessed by screening patients for subsequent hospital admissions and investigating potential links to EDS use.

RESULTS

Seventy-nine patients were managed with the aid of the TIA/Stroke EDS. EDS use resulted in 8 appropriate immediate hospital admissions because of patients being at high risk of stroke. Three patients had delayed admission, but care was fully guideline based and patients had no adverse outcome. Eleven admissions were unrelated to EDS use. Two deaths occurred; these did not result from inappropriate EDS advice.

CONCLUSIONS

Results suggest that TIA/Stroke EDS use is not associated with major morbidity or mortality. Larger studies are needed to draw more definite conclusions regarding the utility of this TIA/Stroke EDS in preventing strokes.

Assessing a standardised approach to measuring corticospinal integrity after stroke with DTI

The structural integrity of the corticospinal tract (CST) after stroke is closely linked to the degree of motor impairment. Simple and reliable methods of assessing white matter integrity within the CST would facilitate the use of this measure in routine clinical practice. Commonly, diffusion tensor imaging is used to measure voxel-wise fractional anisotropy (FA) in a variety of regions of interest (ROIs) representing the CST. Several methods are currently in use with no consensus about which approach is best. ROIs are usually either the whole CST or the posterior limb of the internal capsule (PLIC). These are created manually on brain images or with reference to an individual's CST determined by tractography. Once the ROI has been defined, the FA can be reported as an absolute measure from the ipsilesional side or as a ratio in comparison to the contralesional side. Both corticospinal tracking and manual ROI definition in individual stroke patients are time consuming and subject to bias. Here, we investigated whether using a CST template derived from healthy volunteers was a feasible method for defining the appropriate ROI within which to measure changes in FA. We reconstructed the CST connecting the primary motor cortex to the ipsilateral pons in 23 age-matched control subjects and 21 stroke patients. An average healthy CST template was created from the 23 control subjects. For each patient, FA values were then calculated for both the template CST and for their own CST. We compared patients' FA metrics between the two tracts by considering four measures (FA in the ipsilesional side, FA in the contralesional side, FA ratio of the ipsilesional side to the contralesional side and FA asymmetry between the two sides) and in two tract-based ROIs (whole tract and tract section traversing the PLIC). There were no significant differences in FA metrics for either method, except for contralesional FA. Furthermore, we found that FA metrics relating to CST damage all correlated with motor ability post-stroke equally well. These results suggest that the healthy CST template could be a surrogate structure for defining tract-based ROIs with which to measure stroke patients' FA metrics, avoiding the necessity for CST tracking in individual patients. CST template-based automated quantification of structural integrity would greatly facilitate implementation of practical clinical applications of diffusion tensor imaging.

•

Corticospinal tract (CST) integrity can be assessed using fractional anisotropy.

•

Defining corticospinal tract ROIs in individual stroke patients is open to bias.

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FA-based CST integrity was equivalent when using individual or control CST ROIs.

•

FA-based CST integrity in either ROI correlated with motor impairment equally well.

•

Assessment of CST integrity with standard CST ROIs is feasible.

Agraphia caused by left thalamic hemorrhage

A 71-year-old right-handed man was admitted to our hospital with right hemiparesis and sensory impairment associated with mild aphasia. Although aphasia gradually resolved within 2 weeks after stroke onset, his writing ability remained disturbed. A computed tomography (CT) scan at stroke onset revealed a hematoma in the left thalamus, but no cortical lesions were observed. Further, a single-photon emission CT (SPECT) scan showed decreased blood flow in the left thalamus, in the cortical region extending from the left superior temporal gyrus to the parietal lobe, and in the frontal lobe. It is possible that agraphia may have directly resulted from the thalamic lesion, but SPECT findings strongly suggested that a general decrease in left cortical function concomitant with a disruption of the thalamocortical and cortico-thalamocortical projection fibers produced these cognitive deficits.

NIRS in clinical neurology - a 'promising' tool?

Near-infrared spectroscopy (NIRS) has become a relevant research tool in neuroscience. In special populations such as infants and for special tasks such as walking, NIRS has asserted itself as a low resolution functional imaging technique which profits from its ease of application, portability and the option to co-register other neurophysiological and behavioral data in a 'near natural' environment. For clinical use in neurology this translates into the option to provide a bed-side oximeter for the brain, broadly available at comparatively low costs. However, while some potential for routine brain monitoring during cardiac and vascular surgery and in neonatology has been established, NIRS is largely unknown to clinical neurologists. The article discusses some of the reasons for this lack of use in clinical neurology. Research using NIRS in three major neurologic diseases (cerebrovascular disease, epilepsy and headache) is reviewed. Additionally the potential to exploit the established position of NIRS as a functional imaging tool with regard to clinical questions such as preoperative functional assessment and neurorehabilitation is discussed.

Stroke in primary hyperoxaluria type I

We report the case of a 27-year-old man with a history of previously undiagnosed renal disease that presented with multiple cerebrovascular infarctions. Workup for traditional causes of cerebrovascular infarction including cardiac telemetry, multiple echocardiograms, and hypercoagulative workup was negative. However, a transcranial Doppler detected circulating microemboli at the rate of 14 per hour. A serum oxalate level greater than the supersaturation point of calcium oxalate was detected, providing a potential source of the microemboli. Furthermore, serial imaging recorded rapid mineralization of the infarcted territories. In the absence of any proximal vessel irregularities, atherosclerosis, valvular abnormalities, arrhythmias, or systemic shunt as potential stroke etiology in this patient, we propose that circulating oxalate precipitate may be a potential mechanism for stroke in patients with primary oxalosis.

Intra-arterial revascularisation therapy for acute ischaemic stroke: initial experience in a Hong Kong hospital

OBJECTIVES

To assess the outcome of acute ischaemic stroke patients who received intra-arterial therapy in our unit.

DESIGN

Case series.

SETTING

A tertiary hospital in Hong Kong.

PATIENTS

Patients with ischaemic stroke due to large artery occlusion treated within 6 hours from symptom onset between January 2007 and May 2011.

INTERVENTION

Acute intra-arterial revascularisation therapy.

MAIN OUTCOME MEASURES

Primary outcome was functional independence (modified Rankin Scale score of ≤ 2) at 3 months. Secondary outcome was rate of recanalisation. Safety outcomes were symptomatic intracranial haemorrhage and 3-month mortality.

RESULTS

Twenty-one patients with a mean age of 67 years fulfilled the inclusion criteria. Their mean National Institutes of Health Stroke Scale score was 18. The mean onset-to-puncture time was 212 minutes. Nine received intra-arterial tissue plasminogen activator alone, 11 had an adjunctive mechanical thrombectomy, and one received balloon angioplasty without tissue plasminogen activator. At the end of the procedure, thrombolysis grade 2a or better was attained in 18 (86%) of the patients, and 8 (38%) achieved functional independence at 3 months. Rates of symptomatic intracranial haemorrhage and 3-month mortality were 10% and 24%, respectively.

CONCLUSION

In this setting, intra-arterial revascularisation therapy appeared safe and efficacious for this selected group of ischaemic stroke patients with large artery occlusions. Experience gained from this pilot study may help improve clinical outcomes of such patients.

Understanding the reasons behind the low utilisation of thrombolysis in stroke

BACKGROUND

Thrombolysis remains the only approved therapy for acute ischaemic stroke (AIS); however, its utilisation is reported to be low.

AIMS

This study aimed to determine the reasons for the low utilisation of thrombolysis in clinical practice.

METHOD

Five metropolitan hospitals comprising two tertiary referral centres and three district hospitals conducted a retrospective, cross-sectional study. Researchers identified patients discharged with a principal diagnosis of AIS over a 12-month time period (July 2009-July 2010), and reviewed the medical record of systematically chosen samples.

RESULTS

The research team reviewed a total of 521 records (48.8% females, mean age 74.4 ± 14 years, age range 5-102 years) from the 1261 AIS patients. Sixty-nine per cent of AIS patients failed to meet eligibility criteria to receive thrombolysis because individuals arrived at the hospital later than 4.5 hours after the onset of symptoms. The factors found to be positively associated with late arrival included confusion at onset, absence of a witness at onset and waiting for improvement of symptoms. However, factors negatively associated with late arrival encompassed facial droop, slurred speech and immediately calling an ambulance. Only 14.7% of the patients arriving within 4.5 hours received thrombolysis. The main reasons for exclusion included such factors as rapidly improving symptoms (28.2%), minor symptoms (17.2%), patient receiving therapeutic anticoagulation (6.7%) and severe stroke (5.5%).

CONCLUSION

A late patient presentation represents the most significant barrier to utilising thrombolysis in the acute stroke setting. Thrombolysis continues to be currently underutilised in potentially eligible patients, and additional research is needed to identify more precise criteria for selecting patients for thrombolysis.

Anxiety and depression associated with caregiver burden in caregivers of stroke survivors with spasticity

OBJECTIVE

To investigate the relationship between anxiety/depression and caregiver burden in informal caregivers of stroke survivors with spasticity.

DESIGN

Data were collected via online surveys from informal caregivers 18 years or older who cared for stroke survivors.

SETTING

Internet-based survey.

PARTICIPANTS

2007 through 2009 U.S. National Health and Wellness Survey database or Lightspeed Research general panel respondents (N=153).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Anxiety and depression were self-reported by the caregiver as a physician diagnosis. Depression severity was measured by the Patient Health Questionnaire-9 (PHQ-9). Caregiver burden was measured by the Oberst Caregiving Burden Scale (OCBS) and the Bakas Caregiving Outcomes Scale (BCOS). Logistic regression analyses were conducted with anxiety, depression, and the PHQ-9 depression severity categories as a result of each caregiver burden scale.

RESULTS

Data were analyzed for 153 informal caregivers; they were mostly women (70.6%) and white (78.4%), with a mean age of 51.6 years. For every 1-point increase in the OCBS Difficulty Scale, the odds of anxiety or depression were 2.57 times as great (P<.001) and 1.88 times as great (P=.007), respectively. The odds of PHQ-9 severe depression versus all other categories combined were 2.48 times as great (P<.001). For every 1-point decrease in the BCOS, the odds of anxiety or depression were 2.43 times as great (P<.001) and 2.27 times as great (P=.002), respectively. The odds of PHQ-9 severe depression versus all other categories combined were 4.55 times as great (P<.001).

CONCLUSIONS

As caregiver burden increases, caregivers are more likely to have anxiety and depression. Depression severity also increases. Providing treatment to stroke survivors with spasticity that lessens the time and more importantly, the difficulty of caregiving may lead to a reduction in caregiver anxiety and depression.

Hydrodynamic comparison of the Penumbra system and commonly available syringes in forced-suction thrombectomy

BACKGROUND

The Penumbra system uses a coaxial separator and continuous extracorporeal suction to remove a clot from a cerebral artery. Forced-suction thrombectomy (FST) involves aspirating clots through the same reperfusion catheter using only a syringe, decreasing the procedure time and supplies needed.

OBJECTIVE

To evaluate multiple combinations of catheters and syringes to determine the optimal pairing for use in FST.

METHODS

Tests were performed using both the Penumbra system and syringes to aspirate water through Penumbra 0.041 inch (041), 4Max, 0.054 inch (054) and 5Max reperfusion catheters and a shuttle sheath. Dynamic pressure and flow at the catheter tip were calculated from the fill times for each system. Static pressure and force for each aspiration source were determined with a vacuum gauge.

RESULTS

All syringes provided significantly higher dynamic pressure at the catheter tip than the Penumbra system (p<0.001). Increasing syringe volume significantly increased static pressure (p<0.001). Both flow and aspiration force significantly increased with catheter size (p<0.001). Cases are presented to demonstrate the clinical value of the laboratory principles.

CONCLUSIONS

Maximizing static and dynamic pressure when performing FST is achieved by aspirating with a syringe possessing both the largest volume and the largest inlet diameter available. Maximizing aspiration force and flow rate is achieved by using the largest catheter possible.

Thrombolysis of an acute stroke presentation with an incidental unruptured aneurysm

Many patients with acute ischaemic stroke have contraindications to thrombolytic therapy. We describe a 45 yr old Afro-Caribbean female with HbSC disease whom was electively admitted for a cerebral angiogram to evaluate an intracavernous aneurysm measuring 20 mm in diameter. During the procedure, she suffered a right MCA territory ischaemic event with a NIHSS of 10. A CT angiogram demonstrated no dissection and no evidence of a major vessel occlusion. Tissue plasminogen activator (tPA) was administered intravenously within 60 minutes of symptom onset. She had clinical and haematological evidence of a painful sickle cell crisis and required manual exchange transfusion within a few hours of thrombolysis. This is the first reported case of the use of thrombolysis for acute stroke in a sickle cell crisis; and in the presence of such a large unruptured aneurysm. A registry of unusual thrombolysis cases might help clinicians in cases when there is little evidence to support decision-making.

Treating blood pressure to prevent strokes: The age factor

The importance of systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure (PP), on the incidence of coronary heart disease (CHD) and stroke are known. However, the importance of blood pressure (BP)-age shifts regarding the stroke incidence is not clearly known. The BP changes with the advancement of age from the predominance of DBP in the young to the predominance of SBP in the old. This change is due to the stiffening of the large arteries as a result of the aging process and the replacement of the elastic fibers with collagen fibers. This change results in the loss of compliance and the elastic recoil of these vessels leading to increase in pulse wave velocity, central SBP and widening of pulse pressure leading to an increased incidence of CHD and strokes. It has been demonstrated epidemiologically that the SBP rises linearly with age, whereas the DBP rises up to the age of 45-50 years, and then begins to decline after the age of 60 years leading to a progressive widening of PP. Several studies have shown an inverse relationship between DBP and CHD, whereas no such relationship has been demonstrated for stroke. However, a recent study showed an inverse relationship with DBP and stroke when it dropped below 71 mmHg in subjects 50 years of age or older. In contrast, there was a positive association between BP and stroke when both SBP and DBP were ≥ 71 mmHg. These findings suggest that in treating systolic hypertension in the elderly to reduce stroke risk, attention should be paid on the potential harm of low DBP and the widening of PP regarding CHD and stroke. The implications of BP shifts with age and the potential risks of low DBP regarding the risk of stroke will be discussed in this concise review.

Thrombolysis in a stroke patient on dabigatran anticoagulation: case report and synopsis of published cases

We present the case of an aphasic 77-year-old stroke patient with left distal M1 occlusion who received rt-PA for thrombolysis while on oral anticoagulant treatment with dabigatran (150 mg b.i.d.). Coagulation parameters were normal (thrombin time 20 s, aPTT 20 s, INR 1.08) and the patient improved from an NIHSS of 15 to 5 within 24 h with sonographic evidence of M1 recanalization. She did not develop intracranial bleeding complications but showed unusually large diffuse skin ecchymoses. In our report, we give an overview of all reported cases of thrombolysis under dabigatran anticoagulation and discuss the questions of medication adherence under novel oral anticoagulants (NOA) and the safety of NOA in terms of secondary intracerebral hemorrhage after stroke.

Women's Health Initiative Hormone Therapy Trials: New insights on Cardiovascular Disease from Additional Years of Follow up

Debate and controversy surrounding the benefits and risks of menopausal hormone therapy (MHT) for prevention of cardiovascular disease has continued in the decade since the cessation of the Women's Health Initiative (WHI) hormone therapy interventions. As a result, many women and their physicians have been reluctant to turn to MHT for relief of vasomotor and other menopausal symptoms. However, several follow-up studies of WHI participants provide additional insight into clinical characteristics of women who are more likely to have favorable outcomes and lower rates of adverse events associated with MHT. This report focuses on those studies that identify characteristics and biomarkers helpful in stratifying risk for an individual. Incorporation of these factors into a benefit:risk model could assist in patient-oriented decision making regarding use of MHT. Personalizing treatment offers the potential to minimize risk and improve health outcomes.

Acute vertebral artery origin occlusion leading to basilar artery thrombosis successfully treated by angioplasty with stenting and intracranial fibrinolysis

There are few reports describing stroke due to the acute occlusion of the vertebral artery (VA) origin successfully treated by endovascularily. The authors report a case of 78-year-old man suffering from stroke owing to acute VA origin occlusion associated with contralateral hypoplastic VA leading to basilar artery (BA) thrombosis. Cerebral angiography demonstrated that the right VA was occluded at its origin, the left VA was hypoplastic, and BA was filled with thrombus. The occlusion of VA origin was initially passed through with a microcatheter and microwire. Hereafter, angioplasty was performed followed by stenting with a coronary stent. The VA origin was successfully recanalized. Next, a microcatheter was navigated intracranially through the stent and fibrinolysis was performed for BA thrombus. The patient's symptoms gradually improved postoperatively. Stroke due to acute VA origin occlusion leading to BA thrombosis was successfully treated by angioplasty and stenting followed by intracranial fibrinolysis.

Predicting outcome and recovery after stroke with lesions extracted from MRI images

Here, we present and validate a method that lets us predict the severity of cognitive impairments after stroke, and the likely course of recovery over time. Our approach employs (a) a database that records the behavioural scores from a large population of patients who have, collectively, incurred a comprehensive range of focal brain lesions, (b) an automated procedure to convert structural brain scans from those patients into three-dimensional images of their lesions, and (c) a system to learn the relationship between patients' lesions, demographics and behavioural capacities at different times post-stroke. Validation against data collected from 270 stroke patients suggests that our first set of variables yielded predictions that match or exceed the predictive power reported in any comparable work in the available literature. Predictions are likely to improve when other determinants of recovery are included in the system. Many behavioural outcomes after stroke could be predicted using the proposed approach.

•

We use lesion information to predict speech production skills in 270 stroke patients.

•

We validate our approach with both cross-sectional and longitudinal patient data.

•

Better predictions employ more relevant and detailed lesion site information.

Learning curve of Wingspan stenting for intracranial atherosclerosis: single-center experience of 95 consecutive patients

Background

Symptomatic brain hemorrhage was a significant cause of periprocedural stroke or death following stenting in the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis trial, which called into question the safety of Wingspan stenting for intracranial atherosclerosis. This study analyzed the role of a learning curve in the safety and outcome of Wingspan stenting from the experience of 95 consecutive patients at a single center.

Methods

In this prospective study the endpoints were major stroke or death (modified Rankin Scale score >3) within 30 days, other neurological complications, technical procedural problems, technical success in completion of angioplasty and stenting and recurrent ischemic stroke in the corresponding vascular territory after 30 days. Data splitting into quarters was used for learning curve analysis.

Results

The periprocedural major stroke or death rate was 4.2% (4/95), minor stroke rate was 5.3% (5/95), total 9.5% (9/95). The technical procedural problem rate was 11.6% (11/95) and the technical success rate was 93.7% (89/95). The 89 patients were followed for 38.9±22.7 months (median 40.8, range 0.2–72, 3463 patient-months) after stenting. The risk of recurrent ischemic stroke in the corresponding vascular territory was 0.7% per patient per year (2/3463 patient-months). Guidewire- or angioplasty-related hemorrhage was the major cause of periprocedural major stroke or death (3/4, 75%) and did not occur in the last quarter. Periprocedural intracerebral hemorrhage was uncommon and perforator stroke did not occur.

Conclusions

There may be a learning curve for mastering the safety precautions of Wingspan stenting for intracranial atherosclerosis.

The effect of season and temperature variation on hospital admissions for incident stroke events in Maputo, Mozambique

BACKGROUND

Identifying locale-specific patterns regarding the variation in stroke incidence throughout the year and with atmospheric temperature may be useful to the organization of stroke care, especially in low-resource settings.

GOAL

We aimed to describe the variation in the incidence of stroke hospitalizations across seasons and with short-term temperature variation, in Maputo, Mozambique.

METHODS

Between August 1, 2005, and July 31, 2006, we identified 651 stroke events in Maputo dwellers, according to the World Health Organization's STEPwise approach. The day of symptom onset was defined as the index date. We computed crude and adjusted (humidity, precipitation and temperature) incidence rate ratios (IRRs) and 95% confidence intervals (CIs) with Poisson regression.

RESULTS

Stroke incidence did not vary significantly with season (dry versus wet: crude IRR = .98, 95% CI: .84-1.15), atmospheric temperature at the index date, or average atmospheric temperature in the preceding 2 weeks. The incidence rates of stroke were approximately 30% higher when in the previous 10 days there was a decline in the minimum temperature greater than or equal to 3 °C between any 2 consecutive days (variation in minimum temperature -5.1 to -3.0 versus -2.3 to -.4, adjusted IRR = 1.31, 95% CI: 1.09-1.57). No significant associations were observed according to the variation in maximum temperatures.

CONCLUSIONS

Sudden declines in the minimum temperatures were associated with a higher incidence of stroke hospitalizations in Maputo. This provides important information for prediction of periods of higher hospital affluence because of stroke and to understand the mechanisms underlying the triggering of a stroke event.

MicroRNA-17-92 cluster mediates the proliferation and survival of neural progenitor cells after stroke

The role of microRNAs (miRNAs) in mediating adult neurogenesis after stroke has not been extensively studied. The present study investigated the function of the miR17-92 cluster in adult neural progenitor cells after experimental stroke. We found that stroke substantially up-regulated miR17-92 cluster expression in neural progenitor cells of the adult mouse. Overexpression of the miR17-92 cluster either in cultured ischemic neural progenitor cells or in the subventricular zone (SVZ) of ischemic animals significantly increased cell proliferation, whereas inhibition of individual members of the miR17-92 cluster, miR-18a and miR-19a, suppressed cell proliferation and increased cell death. The miR17-92 cluster mediated PTEN (phosphatase and tensin homolog) expression, which is a predicted target of the miR17-92 cluster. Addition of Sonic hedgehog (Shh) protein up-regulated miR17-92 expression and elevated c-Myc protein in ischemic neural progenitor cells, whereas blockade of the Shh signaling pathway down-regulated miR17-92 cluster expression and reduced c-Myc levels. Overexpression of c-Myc up-regulated miR17-92 cluster expression. Intraventricular infusion of Shh and a Shh receptor inhibitor, cyclopamine, to ischemic animals further elevated and suppressed, respectively, miR17-92 cluster expression in the SVZ. These data indicate that the miR17-92 cluster plays an important role in mediating neural progenitor cell function and that the Shh signaling pathway is involved in up-regulating miR17-92 cluster expression.

Mitochondrial Ca2+ uptake from plasma membrane Cav3.2 protein channels contributes to ischemic toxicity in PC12 cells

T-type Ca(2+) channel inhibitors protect hippocampal CA1 neurons from delayed death after global ischemia in rats, suggesting that Cav3.1, Cav3.2, or Cav3.3 channels generate cytotoxic Ca(2+) elevations during anoxia. To test this hypothesis, we measured the Ca(2+) concentration changes evoked by oxygen and glucose deprivation (OGD) in the cytosol and in the mitochondria of PC12 cells. OGD evoked long-lasting cytosolic Ca(2+) elevations that were reduced by Cav3.2 inhibition (50 μm Ni(2+)) and Cav3.1/Cav3.2 silencing and potentiated by Cav3.2 overexpression. The kinetics of the sustained cytosolic Ca(2+) elevations occurring during OGD directly correlated to the extent of cell death measured 20 h after reoxygenation, which was decreased by Ni(2+) and Cav3.1/Cav3.2 silencing and increased by Cav3.2 overexpression. Ni(2+) and Cav3.1/Cav3.2 silencing delayed the decline of cellular ATP during OGD, consistent with a reduction in the Ca(2+) load actively extruded by plasma membrane Ca(2+) pumps. The cytosolic Ca(2+) elevations were paralleled by mitochondrial Ca(2+) elevations that were also increased by Cav3.2 overexpression and decreased by Ni(2+) but not by Cav3.1/Cav3.2 silencing. Overexpression and silencing of the mitochondrial Ca(2+) uniporter, the major mitochondrial Ca(2+) uptake protein, revealed that the cytotoxicity was correlated to the amplitude of the mitochondrial, rather than the cytosolic, Ca(2+) elevations. Selective activation of T-type Ca(2+) channels evoked both cytosolic and mitochondrial Ca(2+) elevations, but only the mitochondrial responses were reduced by Cav3.1/Cav3.2 silencing. We conclude that the opening of Cav3.2 channels during ischemia contribute to the entry of Ca(2+) ions that are transmitted to mitochondria, resulting in a deleterious mitochondrial Ca(2+) overload.

A randomized trial of two home-based exercise programmes to improve functional walking post-stroke

OBJECTIVE

To estimate the relative effectiveness in improving walking ability and other mobility and health outcomes post-stroke of two home-based exercise programmes - stationary cycling and an exercise and walking programme.

DESIGN

An observer-blinded, randomized, pragmatic, trial with repeated measures.

SETTING

Hospital centers in two Canadian cities.

SUBJECTS

People within 12 months of acute stroke who were able to walk >10 meters independently and healthy enough to engage in exercise.

INTERVENTIONS

Two dose-equivalent interventions, one involving stationary cycling and the other disability-targeted interventions were tested. Both protocols required daily moderate intensity exercise at home building up to 30 minutes per day. One group exercised on a stationary bicycle, the second group carried out mobility exercises and brisk walking.

MAIN MEASURES

The primary outcome was walking capacity as measured by the six-minute walk test (6MWT). Secondary outcomes were physical function, role participation, health-related quality of life exercise adherence, and adverse events.

RESULTS

The study failed to meet recruitment targets: 87 participants (cycle group, n = 43; exercise group, n = 44) participated. No significant effects of group or time were revealed for the 6MWT, which was approximately 320 m at randomization. A significant effect for role participation was found in favor of the exercise group (global odds ratio (OR) for cycling vs. exercise was 0.51; 95% confidence interval (CI), 0.27-0.95). Change in the 6MWT between highest and lowest adherence categories was statistically significant (p = 0.022).

CONCLUSIONS

Both programmes were equally effective in maintaining walking capacity after discharge from stroke rehabilitation; or were equally ineffective in improving walking capacity. Clinical Trials Gov number: NCT00786045.

'Regent Suit' training improves recovery of motor and daily living activities in subjects with subacute stroke: a randomized controlled trial

OBJECTIVE

To evaluate the efficacy of an elastic element-based suit, called 'Regent Suit', in improving the recovery of motor and daily living activities in patients experiencing a subacute stroke.

DESIGN

Randomized controlled trial.

SETTING

Neurorehabilitation unit.

SUBJECTS

Sixty patients with subacute stroke who were capable of walking without direct assistance were randomized to an experimental and control group.

INTERVENTIONS

The experimental group attended 20 sessions of neuromotor exercises (e.g. sit-to-stand, balance, gait training) wearing the 'Regent Suit'; the control group performed the same exercises without the 'Regent Suit'.

OUTCOME MEASURES

6-minute walking test, Berg Balance Scale, the Functional Independence Measure, and the Barthel Index. The participants were evaluated before and after training, and after a further six months.

RESULTS

There were no significant between-group differences at baseline. A repeated measure linear mixed model revealed a significant effect of time (p < 0.001), group (p = 0.019), and time-by-group interaction (p < 0.001) in the gait speed in favour of the experimental group. The Berg Balance Scale indicated a significant effect of time (p < 0.001) and time-by-group interaction (p < 0.001). The experimental group also showed greater improvement in Functional Independence Measure and Barthel Index.

DISCUSSION

The study findings showed that an intervention using the 'Regent Suit' is more effective than usual care in improving locomotion and daily living activities in patients with subacute stroke. Further studies might investigate the efficacy of this type of training in chronic stroke patients and the possibility of combining the suit with body weight-supported treadmill training.

Sleep deprivation before stroke is neuroprotective: a pre-ischemic conditioning related to sleep rebound

BACKGROUND AND AIM

We have previously shown in a rat model of focal cerebral ischemia that sleep deprivation after stroke onset aggravates brain damage. Others reported that sleep deprivation prior to stroke is neuroprotective. The main aim of this study was to test the hypothesis that the neuroprotection may be related to an increase in sleep (sleep rebound) during the acute phase of stroke.

METHODS

Male Sprague Dawley rats (n=36) were subjected to continuous polygraphic recordings for baseline, total sleep deprivation (TSD), and 24h after ischemia. TSD for 6h was performed by gentle handling and immediately followed by ischemia. Focal cerebral ischemia was induced by permanent occlusion of distal branches of the middle cerebral artery. Control experiments included ischemia without SD (nSD) and sham surgery with TSD (n=6/group).

RESULTS

Shortly after stroke, the amount of slow wave sleep (SWS) and paradoxical sleep (PS) increased significantly (p<0.05) in the TSD/ischemia, resulting in an increase in the total sleep time by 30% compared to baseline, or by 20% compared with the nSD/ischemia group. The infarct volume decreased significantly by 50% in the TSD/ischemia compared to nSD group (p<0.02). Removal of sleep rebound by allowing TSD-rats sleep for 24h before ischemia eliminated the reduction in the infarct size.

CONCLUSION PRESTROKE

Sleep deprivation results in sleep rebound and reduces brain damage. Sleep rebound may be causally related to the neuroprotection.

Betrixaban compared with warfarin in patients with atrial fibrillation: results of a phase 2, randomized, dose-ranging study (Explore-Xa)

Aims

Patients with atrial fibrillation (AF) are at increased risk of stroke. Betrixaban is a novel oral factor Xa inhibitor administered once daily, mostly excreted unchanged in the bile and with low (17%) renal excretion.

Methods and results

Patients with AF and more than one risk factor for stroke were randomized to one of three blinded doses of betrixaban (40, 60, or 80 mg once daily) or unblinded warfarin, adjusted to an international normalized ratio of 2.0–3.0. The primary outcome was major or clinically relevant non-major bleeding. The mean follow-up was 147 days. Among 508 patients randomized, the mean CHADS₂ score was 2.2; 87% of patients had previously received vitamin K antagonist therapy. The time in therapeutic range on warfarin was 63.4%. There were one, five, five, and seven patients with a primary outcome on betrixaban 40, 60, 80 mg daily, or warfarin, respectively. The rate of the primary outcome was lowest on betrixaban 40 mg (hazard ratio compared with warfarin = 0.14, exact stratified log-rank P-value 0.04, unadjusted for multiple testing). Rates of the primary outcome with betrixaban 60 or 80 mg were more similar to those of wafarin. Two ischaemic strokes occurred, one each on betrixaban 60 and 80 mg daily. There were two vascular deaths, one each on betrixaban 40 mg and warfarin. Betrixaban was associated with higher rates of diarrhoea than warfarin.

Conclusion

Betrixaban was well tolerated and had similar or lower rates of bleeding compared with well-controlled warfarin in patients with AF at risk for stroke.

A French stroke unit experience

OBJECTIVES

Narrow therapeutic window is a major cause of thrombolysis exclusion in acute ischemic stroke. Whether prehospital medicalization increases t-PA treatment rate is investigated in the present study.

PATIENTS AND METHODS

Intrahospital processing times and t-PA treatment were analyzed in stroke patients calling within 6h and admitted in our stoke unit. Patients transferred by our mobile medical team (SAMU) and by Fire Department (FD) paramedics were compared.

RESULTS

193 (61.6%) SAMU patients and 120 (38.4%) FD patients were included within 30 months. Clinical characteristics and onset-to-call intervals were similar in the two groups. Mean door-to-imaging delay was deeply reduced in the SAMU group (52 vs. 159 min, p<0.0001) and was <25 min in 50% of SAMU patients and 14% of FD patients (p<0.0001). SAMU management was the only independent factor of early imaging (p=0.0006). t-PA administration rate was higher in SAMU group than in FD group (42% vs. 28%, p=0.04). Proportion of patients with delayed therapeutic window was higher in FD group than in SAMU group (38% vs. 26%, p<0.0001).

CONCLUSION

Prehospital transfer medicalization promotes emergency room bypass, direct radiology room admission and high thrombolysis rate in acute ischemic stroke.

Carotid endarterectomy—safe and effective in a neurosurgeon's hands: a 25-year single-surgeon experience

OBJECTIVE

Carotid endarterectomy (CEA) is a procedure performed by both vascular surgeons and neurosurgeons in the UK. We present a single neurosurgeon's experience of 728 CEAs over 25 years, performed under both general and local anesthesia, and discuss the results in this context. Our objective was to report on the efficacy of CEA in the hands of a neurosurgeon.

METHODS

Prospective outcome data were collected for all patients who underwent CEA performed by the senior author (A.D.M.) from 1987 to 2011. Data evaluated included patient age, sex, surgical indication, preoperative characteristics, diagnostic modalities used, shunt usage, operative time, any neurological deterioration during or after surgery, and early postoperative problems. Outcome measures used were 30-day death and 30-day disabling stroke. The results were tabulated and analyzed using JMP 8.0.2 (SAS Inc., Cary, NC).

RESULTS

The 30-day death rate was 0.8% and the 30-day disabling stroke rate was 1.7% in our series. The mean operative time was 135 minutes (±38.1), and the mean clamp time was 28.4 minutes (±8.5). In the subset of patients who had the operation performed under local anesthesia (n = 616), the disabling stroke rate was 1.6% and the death rate was 0.6%. In the subset of asymptomatic patients (n = 194), the 30-day death and 30-day disabling stroke rates were each 1%. Postoperative complications were uncommon.

CONCLUSIONS

According to our data, CEA under local anesthesia is safe procedure in the hands of a neurosurgeon and would be recommended according to the clinical presentation and local guidelines.

The role of Willis circle variations during unilateral selective cerebral perfusion: a study of 500 circles

OBJECTIVES

During unilateral selective cerebral perfusion (uSCP), with right axillary artery or brachiocephalic trunk cannulation, the brain receives blood only via the right common carotid artery and right vertebral artery (VA). The left hemisphere is perfused mainly through the circle of Willis (CW). However, at least 50% of individuals have some variation in the CW. The aim of the present work was to study the variations in CW and VA that could have an impact on haemodynamics during uSCP.

METHODS

From May 2005 to March 2012, a total number of 250 circles obtained via routine dissection for medico-legal reasons were examined. The external diameters of all CW segments and both VAs were measured. From January 2008 to March 2012, a total number of 250 patients subjected to computed tomographic angiography of the CW were also examined.

RESULTS

Nine evident configurations of the CW that could cause hypoperfusion during uSCP were observed. They were subdivided in to seven types, according to location and the number of major vessels at risk of hypoperfusion. Type IA: hypo/aplasia of left posterior communicating artery (PComA), found in 35.6% of cases; Type IB: hypo/aplasia of anterior communicating artery (AComA), found in 2% of cases; Type IIA: hypo/aplasia of both left PComA and AComA, found in 4.8% of cases; Type IIB: hypo/aplasia of precommunicating (P1) segment of left posterior cerebral artery or right VA, found in 9.2% of cases; Type IIIA: hypo/aplasia of precommunicating (A1) segment of right anterior cerebral artery, found in 6% of cases; Type IIIB: hypo/aplasia of both right VA and AComA, found in 0.2% of cases; Type IV: hypo/aplasia of both right A1 and right VA or both right A1 and left P1, found in 0.8% of cases. All types were present in 58.6% of all examined CWs.

CONCLUSIONS

Our results show that CW variations are present in a significant number of patients. Our data support the need for extensive preoperative examination and meticulous intraoperative monitoring of cerebral perfusion during uSCP. Finally, our data support the superiority of bilateral SCP over uSCP, because most of the variations reported do not have haemodynamic significance during bilateral SCP.