Stroke as a career option for neurologists.

Stroke is one of the most common acute neurological disorders and a leading cause of disability worldwide. Evidence-based treatments over the last two decades have driven a revolution in the clinical management and design of stroke services. We need a highly skilled, multidisciplinary workforce that includes neurologists as core members to deliver modern stroke care. In the UK, the dedicated subspecialty training programme for stroke medicine has recently been integrated into the neurology curriculum. All neurologists will be trained to contribute to each aspect of the stroke care pathway. We discuss how training in stroke medicine is evolving for neurologists and the opportunities and challenges around practising stroke medicine in the UK and beyond.

Cerebrovascular disease in sickle cell disease.

Sickle cell disease (SCD) is the most common type of hereditary anaemia and genetic disorder worldwide. Cerebrovascular disease is one of its most devastating complications, with consequent increased morbidity and mortality. Current guidelines suggest that children and adults with SCD who develop acute ischaemic stroke should be transfused without delay. Those with acute ischaemic stroke aged over 18 years who present within 4.5 hours of symptom onset should be considered for intravenous thrombolysis; older patients with conventional vascular risk factors are the most likely to benefit. Endovascular thrombectomy should be considered carefully in adults with SCD as there are few data to guide how the prevalence of cerebral vasculopathy may confound the expected benefits or risks of intervention. We present a practical approach to cerebrovascular disease in sickle cell patients based on the available evidence and our experience.

Vascular Collagen Type-IV in Hypertension and Cerebral Small Vessel Disease.

BACKGROUND: Cerebral small vessel disease (SVD) is common in older people and causes lacunar stroke and vascular cognitive impairment. Risk factors include old age, hypertension and variants in the genes COL4A1/COL4A2 encoding collagen alpha-1(IV) and alpha-2(IV), here termed collagen-IV, which are core components of the basement membrane. We tested the hypothesis that increased vascular collagen-IV associates with clinical hypertension and with SVD in older persons and with chronic hypertension in young and aged primates and genetically hypertensive rats. METHODS: We quantified vascular collagen-IV immunolabeling in small arteries in a cohort of older persons with minimal Alzheimer pathology (N=52; 21F/31M, age 82.8±6.95 years). We also studied archive tissue from young (age range 6.2-8.3 years) and older (17.0-22.7 years) primates (M mulatta) and compared chronically hypertensive animals (18 months aortic stenosis) with normotensives. We also compared genetically hypertensive and normotensive rats (aged 10-12 months). RESULTS: Collagen-IV immunolabeling in cerebral small arteries of older persons was negatively associated with radiological SVD severity (ρ: -0.427, P=0.005) but was not related to history of hypertension. General linear models confirmed the negative association of lower collagen-IV with radiological SVD (P<0.017), including age as a covariate and either clinical hypertension (P<0.030) or neuropathological SVD diagnosis (P<0.022) as fixed factors. Reduced vascular collagen-IV was accompanied by accumulation of fibrillar collagens (types I and III) as indicated by immunogold electron microscopy. In young and aged primates, brain collagen-IV was elevated in older normotensive relative to young normotensive animals (P=0.029) but was not associated with hypertension. Genetically hypertensive rats did not differ from normotensive rats in terms of arterial collagen-IV. CONCLUSIONS: Our cross-species data provide novel insight into sporadic SVD pathogenesis, supporting insufficient (rather than excessive) arterial collagen-IV in SVD, accompanied by matrix remodeling with elevated fibrillar collagen deposition. They also indicate that hypertension, a major risk factor for SVD, does not act by causing accumulation of brain vascular collagen-IV.

The PASTIS trial: Testing tadalafil for possible use in vascular cognitive impairment.

INTRODUCTION: There are few randomized clinical trials in vascular cognitive impairment (VCI). This trial tested the hypothesis that the PDE5 inhibitor tadalafil, a widely used vasodilator, increases cerebral blood flow (CBF) in older people with symptomatic small vessel disease, the main cause of VCI. METHODS: In a double-blind, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥7 days apart (randomized to order of treatment). The primary endpoint, change in subcortical CBF, was measured by arterial spin labelling. RESULTS: Tadalafil increased CBF non-significantly in all subcortical areas (N = 55, age: 66.8 (8.6) years) with greatest treatment effect within white matter hyperintensities (+9.8%, P = .0960). There were incidental treatment effects on systolic and diastolic blood pressure (-7.8, -4.9 mmHg; P < .001). No serious adverse events were observed. DISCUSSION: This trial did not identify a significant treatment effect of single-administration tadalafil on subcortical CBF. To detect treatment effects may require different dosing regimens.

Spontaneous spinal cord infarction: a practical approach.

Spontaneous spinal cord infarction is significantly less common than cerebrovascular disease. Because of the tight anatomical distribution of pathways in the cord, small spinal cord infarcts usually give more obvious symptoms and signs than similar lesions in the brain. Large epidemiological stroke studies have generally not included spinal cord stroke and so the incidence of vascular syndromes in the spinal cord is unknown. Management and prevention strategies for spontaneous spinal cord infarcts stem from small case series and case reports. Patient outcomes from spinal cord infarction are better with prompt recognition, timely management and prevention of associated medical complications arising from paraplegia, tetraplegia, neurogenic bladder and bowel dysfunction. The process of rehabilitation following spinal cord infarction is an evolving area.

Innate Immune Anti-Inflammatory Response in Human Spontaneous Intracerebral Hemorrhage.

Background and Purpose: Spontaneous intracerebral hemorrhage (sICH) is a common form of hemorrhagic stroke, with high mortality and morbidity. Pathophysiological mechanisms in sICH are poorly understood and treatments limited. Neuroinflammation driven by microglial-macrophage activation contributes to brain damage post-sICH. We aim to test the hypothesis that an anti-inflammatory (repair) process occurs in parallel with neuroinflammation in clinical sICH. Methods: We performed quantitative analysis of immunohistochemical markers for microglia and macrophages (Iba1, CD68, TMEM119, CD163, and CD206) in brain tissue biospecimens 1 to 12 days post-sICH and matched control cases. In a parallel, prospective group of patients, we assayed circulating inflammatory markers (CRP [C-reactive protein], total white cell, and monocyte count) over 1 to 12 days following sICH. Results: In 27 supratentorial sICH cases (n=27, median [interquartile range] age: 59 [52­80.5], 14F/13M) all microglia-macrophage markers increased post-sICH, relative to control brains. Anti-inflammatory markers (CD163 and CD206) were elevated alongside proinflammatory markers (CD68 and TMEM119). CD163 increased progressively post-sICH (15.0-fold increase at 7­12 days, P<0.001). CD206 increased at 3 to 5 days (5.2-fold, P<0.001) then returned to control levels at 7 to 12 days. The parenchymal immune response combined brain-derived microglia (TMEM119 positive) and invading monocyte-derived macrophages (CD206 positive). In a prospective sICH patient cohort (n=26, age 74 [66­79], National Institutes of Health Stroke Scale on admission: 8 [4­17]; 14F/12M) blood CRP concentration and monocyte density (but not white blood cell) increased post-sICH. CRP increased from 0 to 2 to 3 to 5 days (8.3-fold, P=0.020) then declined at 7 to 12 days. Monocytes increased from 0 to 2 to 3 to 5 days (1.8-fold, P<0.001) then declined at 7 to 12 days. Conclusions: An anti-inflammatory pathway, enlisting native microglia and blood monocytes, occurs alongside neuroinflammation post-sICH. This novel pathway offers therapeutic targets and a window of opportunity (3­5 days post-sICH) for delivery of therapeutics via invading monocytes.

The association of neutrophil-lymphocyte ratio and lymphocyte-monocyte ratio with 3-month clinical outcome after mechanical thrombectomy following stroke.

BACKGROUND AND AIM: Neutrophil-lymphocyte ratio (NLR) and lymphocyte-monocyte ratio (LMR) are associated with clinical outcomes in malignancy, cardiovascular disease and stroke. Here we investigate their association with outcome after acute ischaemic stroke treated by mechanical thrombectomy (MT). METHODS: Patients were selected using audit data for MT for acute anterior circulation ischaemic stroke at a UK centre from May 2016-July 2017. Clinical and laboratory data including neutrophil, lymphocyte and monocyte count tested before and 24 h after MT were collected. Poor functional outcome was defined as modified Rankin Scale (mRS) of 3-6 at 3 months. Multivariable logistic regression analyses were performed to explore the relationship of NLR and LMR with functional outcome. RESULTS: One hundred twenty-one patients (mean age 66.4 ± 16.7, 52% female) were included. Higher NLR (adjusted OR 0.022, 95% CI, 0.009-0.34, p = 0.001) and lower LMR (adjusted OR - 0.093, 95% CI (- 0.175)-(- 0.012), p = 0.025) at 24-h post-MT were significantly associated with poorer functional outcome when controlling for age, baseline NIHSS score, infarct size, presence of good collateral supply, recanalisation and symptomatic intracranial haemorrhage on multivariate logistic regression. Admission NLR or LMR were not significant predictors of mRS at 3 months. The optimal cut-off values of NLR and LMR at 24-h post-MT that best discriminated poor outcome were 5.5 (80% sensitivity and 60% specificity) and 2.0 (80% sensitivity and 50% specificity), respectively on receiver operating characteristic curve analysis. CONCLUSION: NLR and LMR tested at 24 h after ictus or intervention may predict 3-month functional outcome.

What Proportion of Patients Admitted with Stroke or Transient Ischemic Attack May Be Suitable for Newer Cholesterol-Lowering Treatment?

BACKGROUND: Protein convertase subtilisin-kexin type 9 (PCSK9) inhibitors effectively clear low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C). We evaluated stroke admissions potentially eligible for more intensive cholesterol treatment. METHODS: Retrospective analysis of consecutive admissions to a hyperacute stroke unit over 5 months in 2017. Records were individually searched. Data were collected on diagnosis, risk factors, and stroke work-up. European Society of Cardiology and European Atherosclerosis Society guidelines for the management of dyslipidaemias were used for screening patients eligible for PCSK9 inhibitors. RESULTS: Of 650 patient admissions: 351 (54%) had acute ischemic stroke or transient ischemic attack (TIA), 80 (12%) hemorrhage, and 219 (34%) mimic syndromes. Patients with hemorrhage (n = 80), mimic syndromes (n = 219), and absent LDL-C, or non-HDL-C testing (n = 27) were subsequently excluded. 324 patients with acute ischemic stroke and TIA were further screened for PCSK9-inhibitor treatment eligibility. Forty-one (13%) patients with LDL-C greater than or equal to 1.8mmol/L (≥70 mg/dL) on maximal tolerated statin dose and with concomitant "very high vascular risk" were identified. "Very high vascular risk" was defined as a documented history of cardiovascular disease and/or peripheral arterial disease. Of 41 patients eligible for PCSK9 inhibitors, median age was 82 years (range 53-96); median vascular risk factors were 2 (range 1-5); 7 (17%) had TIA; 13 (31%) had history of preceding cerebrovascular events, 13 (31%) diabetes mellitus, 17 (42%) cardioembolic events, 9 (22%) lacunar syndrome, 11 (22%) symptomatic internal carotid artery stenosis (n = 9 were >70%), and 4 (10%) undetermined aetiology. Eighty-three percent patients eligible for PCSK9 inhibitors also had non-HDL-C values greater than or equal to 2.6 mmol/L. CONCLUSIONS: Up to 13% of unselected acute ischemic stroke or TIA patients admitted to a hyper-acute stroke unit were potentially suitable for more intensive cholesterol treatment. Our data may act as a useful guide for sample size selection in future stroke trials testing PCSK9 inhibitors.

High on-clopidogrel platelet reactivity in ischaemic stroke or transient ischaemic attack: Systematic review and meta-analysis.

OBJECTIVES: To assess the prevalence of high on-clopidogrel platelet reactivity (HCPR) in patients with ischaemic stroke or transient ischaemic attack (IS/TIA), their outcome and genetic basis of on-treatment response variability in IS/TIA patients. METHODS: We conducted a comprehensive search of PubMed and EMBASE from their inceptions to March 9, 2019. Studies that reported absolute numbers/percentages of HCRP at any time point after IS/TIA onset evaluated with any type of platelet function tests, clinical outcomes and genotyping data were included. RESULTS: Among 21 studies of 4312 IS/TIA patients treated with clopidogrel, the pooled prevalence of HCPR was 28% (95%CI: 24-32%; high heterogeneity: I2 = 88.2%, p < 0.001). Heterogeneity degree diminished across groups defined by the HCPR testing method. Clopidogrel non-responder IS/TIA patients had poorer outcome compared to responders (RR = 2.09, 95%CI: 1.61-2.70; p = 0.036; low heterogeneity across studies: I2 = 27.4%, p = 0.210). IS/TIA carriers of CYP2C19*2 or CYP2C19*3 loss of function alleles had a higher risk of HCPR compared to wild type (RR = 1.69, 95%CI: 1.47-1.95; p < 0.001; I2 = 0.01%, p = 0.475). CONCLUSIONS: This systematic review shows a high prevalence of clopidogrel resistance in IS/TIA and poor outcome in these patients. CYP2C19 polymorphisms may potentially influence clopidogrel resistance.

Patent foramen ovale.

Patent foramen ovale (PFO) is the most common anatomical cause of an interatrial shunt. It is usually asymptomatic but may cause paradoxical embolism, manifesting as stroke, myocardial infarction or visceral/peripheral ischaemia. PFO is a risk factor for stroke and may be associated with migraine with aura. New evidence suggests PFO closure reduces the risk of recurrent ischaemic stroke in a highly selected population of stroke survivors: those aged 60 years or younger with a cryptogenic stroke syndrome, a large right-to-left shunt, an atrial septal aneurysm and no evidence of atrial fibrillation. They benefit from percutaneous PFO closure in addition to antiplatelet therapy, rather than antiplatelet therapy alone. Current evidence does not support PFO closure in the treatment of migraine.

Hypersensitivity reactions to recombinant tissue plasminogen activator.

Recombinant tissue plasminogen activator (rtPA) is currently the only approved thrombolytic agent for treating acute ischaemic stroke that is widely used in clinical practice. However, it may cause haemorrhage and hypersensitivity reactions. Orolingual angioedema is an infrequent, usually mild but potentially life threatening, hypersensitivity reaction to rtPA. Our understanding of the basic biology of angioedema has increased in recent years. There is growing evidence that rtPA-induced orolingual angioedema is driven mainly by bradykinin generation rather than it being an anaphylactic response. Monitoring is important because orolingual angioedema may evolve and compromise airways and a small number do have angioedema as part of systemic anaphylaxis. There are no published guidelines for treating rtPA-induced orolingual angioedema, although some evidence suggests that those refractory to standard antianaphylactic agents may resolve with bradykinin B2 receptor antagonists. It is important that responses to orolingual angioedema are proportionate and that patients are closely monitored.

Management of a wake-up stroke.

Current national guidelines advocate intravenous thrombolysis to treat patients with acute ischaemic stroke presenting within 4.5 hours from symptom onset, and thrombectomy for patients with anterior circulation ischaemic stroke from large vessel occlusion presenting within 6 hours from onset. However, a substantial group of patients presents with acute ischaemic stroke beyond these time windows or has an unknown time of onset. Recent studies are set to revolutionise treatment for these patients. Using MRI diffusion/FLAIR (fluid-attenuated inversion recovery) mismatch, it is possible to identify patients within 4.5 hours from onset and safely deliver thrombolysis. Using CT perfusion imaging, it is possible to identify subjects with a middle cerebral artery syndrome who have an extensive area of ischaemic brain but as yet have only a small area of infarction who may benefit from urgent thrombectomy in up to 24 hours. Here, we highlight the recent advances in late window stroke treatment and their potential contribution to clinical practice.

Training in neurology: lessons learnt.

There is no consensus on how to structure and deliver neurology training. The General Medical Council's annual National Training Survey indicates that the quality of UK neurology training is very variable, but does not explain this variation. We used the survey data to identify the four highest and lowest performing sites for neurology training across the UK. We conducted semistructured interviews with groups of local trainees and, separately, local trainers in an exploratory qualitative study, and identified common themes across a range of aspects of neurology training. Here we present our findings, share case studies from top-performing sites and make recommendations on how best to train a neurologist.

Cerebral catheter angiography and its complications.

Catheter-based angiography is an important but invasive procedure in vascular neurology. It is used mainly for diagnosis and for planning treatment in patients with a suspected underlying vascular abnormality. It is often performed as a semiurgent, planned investigation or linked to an interventional procedure. Cerebral angiography provides high-resolution, three-dimensional, pathoanatomical data about the cerebral vasculature and also allows real-time analysis of blood flow. Contrast injections can be repeated to identify subtleties. A physical intervention may also follow angiography. For these reasons, angiography remains the gold standard for delineating vascular lesions of the brain (and spine). Permanent neurological complications are rare, approximately 1%, but become increasingly common in patients aged over 55 years. The main complications are embolic stroke, groin haematoma and contrast-induced nephropathy. In the new era of thrombectomy, it may transpire that other specialists including neurologists may learn to perform the procedure and to manage its complications.

Acute neurology simulation training.

Acute neurology is the neurological care that a patient receives in an emergency or urgent care situation. This can be adapted successfully to training in a simulation where learners are immersed in realistic scenarios in a safe, controlled and reproducible environment. In addition to teaching important technical skills that improve knowledge of the diagnosis and management of acute neurology, the simulation laboratory provides a valuable setting to improve human factors and non-technical skills, such as teamwork and leadership. Simulations are best conducted in a multiprofessional group with scenarios that allow different team members (nurses, physician associates, core medical and specialist trainees) to participate in their actual role. These training sessions require clear learning objectives, and involve designing the scenarios, running the session and ending with a structured debriefing to consolidate learning. The ultimate aim is to improve the team's effectiveness to deliver safe acute neurological care in the emergency department and on the wards.

Testing the cognitive effects of tadalafil. Neuropsychological secondary outcomes from the PASTIS trial.

Cerebral small vessel disease (SVD) is a major cause of cognitive impairment in older people. As secondary endpoints in a phase-2 randomised clinical trial, we tested the effects of single administration of a widely-used PDE5 inhibitor, tadalafil, on cognitive performance in older people with SVD. In a double-blinded, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥ 7 days apart (randomised to order of treatment). The Montreal Cognitive Assessment (MOCA) was administered at baseline, alongside a measure to estimate optimal intellectual ability (Test of Premorbid Function). Then, before and after treatment, a battery of neuropsychological tests was administered, assessing aspects of attention, information processing speed, working memory and executive function. Sixty-five participants were recruited and 55 completed the protocol (N = 55, age: 66.8 (8.6) years, range 52-87; 15/40 female/male). Median MOCA score was 26 (IQR: 23, 27], range 15-30). No significant treatment effects were seen in any of the neuropsychological tests. There was a trend towards improved performance on Digit Span Forward (treatment effect 0.37, C.I. 0.01, 0.72; P = 0.0521). We did not identify significant treatment effects of single-administration tadalafil on neuropsychological performance in older people with SVD. The trend observed on Digit Span Forward may help to inform future studies. Clinical trial registration: http://www.clinicaltrials.gov. Unique identifier: NCT00123456, https://eudract.ema.europa.eu. Unique identifier: 2015-001,235-20NCT00123456.

Maintaining training progression in remote-working junior doctors.

The COVID-19 pandemic has resulted in periods of remote working for some junior doctors, due to shielding and clinical vulnerability. This report offers practical guidance for junior doctors and their supervisors on how to make a period of remote working safe and effective, while maintaining education, training progression and morale. We outline specific challenges and practicalities that should be considered prior to commencing remote working and discuss what tasks and activities are best suited to a remote-working junior doctor. We offer a positive outlook that, with adequate support, a junior doctor can continue to progress in their training while working remotely, and can make a period of remote working an opportunity for personal and professional development while remaining an effective and valuable member of the clinical team.

Strokectomy for malignant middle cerebral artery infarction: experience and meta-analysis of current evidence.

Strokectomy means surgical excision of infarcted brain tissue post-stroke with preservation of skull integrity, distinguishing it from decompressive hemicraniectomy. Both can mitigate malignant middle cerebral artery (MCA) syndrome but evidence regarding strokectomy is sparse. Here, we report our data and meta-analysis of strokectomy compared to hemicraniectomy for malignant MCA infarction. All malignant MCA stroke cases requiring surgical intervention in a large tertiary centre (January 2012-December 2017, N = 24) were analysed for craniotomy diameter, complications, length of follow-up and outcome measured using the modified Rankin score (mRS). Good outcome was defined as mRS 0-3 at 12 months. In a meta-analysis, outcome from strokectomy (pooled from our cohort and published strokectomy studies) was compared with hemicraniectomy (our cohort pooled with published DECIMAL, DESTINY and HAMLET clinical trial data). In our series (N = 24, 12/12 F/M; mean age: 45.83 ± 8.91, range 29-63 years), 4 patients underwent strokectomy (SC) and 20 hemicraniectomy (HC). Among SC patients, craniotomy diameter was smaller, relative to HC patients (86 ± 13.10 mm, 120 ± 4.10 mm, respectively; p = 0.003), complications were less common (25%, 55%) and poor outcomes were less common (25%, 70%). In the pooled data (N = 41 SC, 71 HC), strokectomy tended towards good outcome more than hemicraniectomy (OR 2.2, 95% CI 0.99-4.7; p = 0.051). In conclusion, strokectomy may be non-inferior, lower risk and cost saving relative to hemicraniectomy sufficiently to be worthy of further investigation and maybe a randomised trial.

Vasculocentric Axonal NfH in Small Vessel Disease.

Cerebral small vessel disease (SVD) causes lacunar stroke and vascular cognitive impairment in older people. The pathogenic pathways from vessel pathology to parenchymal damage in SVD are unknown. Neurofilaments are axonal structural proteins. Neurofilament-light (NfL) is an emerging biomarker for neurological disease. Here, we examined the high molecular weight form neurofilament-heavy (NfH) and quantified a characteristic pattern of peri-arterial (vasculocentric) NfH labeling. Subcortical frontal and parietal white matter from young adult controls, aged controls, and older people with SVD or severe Alzheimer disease (n = 52) was immunohistochemically labeled for hyperphosphorylated NfH (pNfH). The extent of pNfH immunolabeling and the degree of vasculocentric axonal pNfH were quantified. Axonal pNfH immunolabeling was sparse in young adults but a common finding in older persons (controls, SVD, or AD). Axonal pNfH was often markedly concentrated around small penetrating arteries. This vasculocentric feature was more common in older people with SVD than in those with severe AD (p = 0.004). We conclude that axonal pNfH is a feature of subcortical white matter in aged brains. Vasculocentric axonal pNfH is a novel parenchymal lesion that is co-located with SVD arteriopathy and could be a consequence of vessel pathology.