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1.
Eur J Neurol ; : e16502, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39392040

RESUMO

BACKGROUND AND PURPOSE: Ambulance trials assessing interventions in suspected stroke patients will recruit patients with currently active symptoms that will resolve into transient ischaemic attack (TIA). The safety and efficacy of glyceryl trinitrate (GTN) in the pre-specified subgroup of patients with TIA in the Rapid Intervention with Glyceryl Trinitrate in Hypertensive Stroke Trial 2 (RIGHT-2) was assessed. METHODS: RIGHT-2 was a pre-hospital-initiated multicentre randomized sham-controlled blinded-endpoint trial that randomized patients with presumed ultra-acute stroke within 4 h of symptom onset to transdermal GTN or sham. Final diagnosis was determined by site investigators. The primary outcome was a shift in modified Rankin Scale (mRS) scores at 90 days analysed using ordinal logistic regression reported as adjusted common odds ratio with 95% confidence intervals (CIs). Secondary outcomes included death or dependence (mRS >2). RESULTS: In all, 109 of 1149 (9.5%) patients had a final diagnosis of TIA (GTN 57, sham 52) with mean age 73 (SD 13) years, 19 (17.4%) had pre-morbid mRS >2, and onset to randomization was 80 min (interquartile range 49, 105). GTN lowered blood pressure by 7.4/5.2 mmHg compared with sham by hospital arrival. At day 90, GTN had no effect on shift in mRS scores (common odds ratio for increased dependence 1.47, 95% CI 0.70-3.11) but was associated with increased death or dependence (mRS >2): GTN 29 (51.8%) versus sham 23 (46.9%), odds ratio 3.86 (95% CI 1.09-13.59). CONCLUSIONS: Pre-hospital ultra-acute transdermal GTN did not improve overall functional outcome in patients with investigator-diagnosed TIA compared with sham treatment.

2.
Lancet Neurol ; 23(11): 1087-1096, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39424558

RESUMO

BACKGROUND: Tenecteplase has potential benefits over alteplase, the standard agent for intravenous thrombolysis in acute ischaemic stroke, because it is administered as a single bolus and might have superior efficacy. The ATTEST-2 trial investigated whether tenecteplase was non-inferior or superior to alteplase within 4·5 h of onset. METHODS: We undertook a prospective, randomised, parallel-group, open-label trial with masked endpoint evaluation in 39 UK stroke centres. Previously independent adults with acute ischaemic stroke, eligible for intravenous thrombolysis less than 4·5 h from last known well, were randomly assigned 1:1 to receive intravenous alteplase 0·9 mg/kg or tenecteplase 0·25 mg/kg, by use of a telephone-based interactive voice response system. The primary endpoint was the distribution of the day 90 modified Rankin Scale (mRS) score and was analysed using ordinal logistic regression in the modified intention-to-treat population. We tested the primary outcome for non-inferiority (odds ratio for tenecteplase vs alteplase non-inferiority limit of 0·75), and for superiority if non-inferiority was confirmed. Safety outcomes were mortality, symptomatic intracranial haemorrhage, radiological intracranial haemorrhage, and major extracranial bleeding. The trial was prospectively registered on ClinicalTrials.gov (NCT02814409). FINDINGS: Between Jan 25, 2017, and May 30, 2023, 1858 patients were randomly assigned to a treatment group, of whom 1777 received thrombolytic treatment and were included in the modified intention-to-treat population (n=885 allocated tenecteplase and n=892 allocated alteplase). The mean age of participants was 70·4 (SD 12·9) years and median National Institutes of Health Stroke Scale was 7 (IQR 5-13) at baseline. Tenecteplase was non-inferior to alteplase for mRS score distribution at 90 days, but was not superior (odds ratio 1·07; 95% CI 0·90-1·27; p value for non-inferiority<0·0001; p=0·43 for superiority). 68 (8%) patients in the tenecteplase group compared with 75 (8%) patients in the alteplase group died, symptomatic intracerebral haemorrhage (defined by SITS-MOST criteria) occurred in 20 (2%) versus 15 (2%) patients, parenchymal haematoma type 2 occurred in 37 (4%) versus 26 (3%) patients, post-treatment intracranial bleed occurred in 94 (11%) versus 78 (9%) patients, significant extracranial haemorrhage occurred in 13 (1%) versus six (1%) patients, respectively, and angioedema occurred in six (1%) participants in both groups. INTERPRETATION: Tenecteplase 0·25 mg/kg was non-inferior to 0·9 mg/kg alteplase within 4·5 h of symptom onset in acute ischaemic stroke. Easier administration of tenecteplase, especially in the context of interhospital transfers, indicates that tenecteplase should be preferred to alteplase for thrombolysis in acute ischaemic stroke. The ATTEST-2 population was large and representative of thrombolysis-eligible patients in the UK and, together with findings from other trials, provides robust evidence supporting the introduction of tenecteplase in preference to alteplase. FUNDING: The Stroke Association and British Heart Foundation.


Assuntos
Fibrinolíticos , AVC Isquêmico , Tenecteplase , Ativador de Plasminogênio Tecidual , Humanos , Tenecteplase/uso terapêutico , Tenecteplase/administração & dosagem , Masculino , Feminino , Ativador de Plasminogênio Tecidual/uso terapêutico , Ativador de Plasminogênio Tecidual/administração & dosagem , Fibrinolíticos/uso terapêutico , Fibrinolíticos/administração & dosagem , Idoso , Pessoa de Meia-Idade , AVC Isquêmico/tratamento farmacológico , Resultado do Tratamento , Idoso de 80 Anos ou mais , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Tempo para o Tratamento
3.
J Neurointerv Surg ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38991735

RESUMO

BACKGROUND: Robust collateral circulation has been linked with better reperfusion and clinical outcomes. It remains unclear how individual assessments of collateral circulation may be translated into clinical practice. METHODS: The pooled Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials (HERMES) angiography dataset was analyzed by a centralized, independent imaging core blinded to other clinical data. Conventional angiography was acquired immediately prior to endovascular therapy. Collaterals were graded with the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN) system and associated with baseline patient characteristics, reperfusion, and day 90 modified Rankin Score (mRS). Both 90-day all-cause mortality and day 90 mRS were modeled via multivariable logistic regression. RESULTS: Angiography was available in 376/605 (62%) patients. Baseline ASPECTS (Alberta Stroke Program Early CT Score) (p=0.043), history of diabetes mellitus (p=0.048), site of occlusion (p<0.001), and degree of subsequent Thrombolysis in Cerebral Infarction (TICI) reperfusion (p<0.001) were associated with collateral grades. ASITN collateral grade was strongly associated with ordinal mRS from baseline to 90 days in an unadjusted analysis (p<0.001). Multivariable regression demonstrated that collateral status is a strong determinant of mRS outcome in the presence of other predictors (OR=1.37 per grade, 95% CI [1.05 to 1.74], p=0.018). By comparing ORs, 1 unit of ASITN was determined to be approximately equivalent to 4.5 points of NIHSS, 11 years of age, 1.5 points of ASPECTS, or 100 min less delay from onset to puncture, in terms of impact on mRS. CONCLUSIONS: Individual collateral physiology may contribute significantly to reperfusion success and clinical outcomes after acute ischemic stroke. Building a consensus for the role of angiographic collateral assessment in the allocation of adjuvant reperfusion therapies may help galvanize a precision medicine approach in stroke.

4.
Stroke ; 55(8): 1982-1990, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39038101

RESUMO

BACKGROUND: Clinicians need simple and highly predictive prognostic scores to assist practical decision-making. We aimed to develop a simple outcome prediction score applied 24 hours after anterior circulation acute ischemic stroke treatment with endovascular thrombectomy and validate it in patients treated both with and without endovascular thrombectomy. METHODS: Using the HERMES (Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials) collaboration data set (n=1764), patients in the endovascular thrombectomy arm were divided randomly into a derivation cohort (n=430) and a validation cohort (n=441). From a set of candidate predictors, logistic regression modeling using forward variable selection was used to select a model that was both parsimonious and highly predictive for modified Rankin Scale (mRS) ≤2 at 90 days. The score was validated in validation cohort, control arm (n=893), and external validation cohorts from the ESCAPE-NA1 (Efficacy and Safety of Nerinetide for the Treatment of Acute Ischaemic Stroke; n=1066) and INTERRSeCT (Identifying New Approaches to Optimize Thrombus Characterization for Predicting Early Recanalization and Reperfusion With IV Alteplase and Other Treatments Using Serial CT Angiography; n=614). RESULTS: In the derivation cohort, we selected 2 significant predictors of mRS ≤2 (National Institutes of Health Stroke Scale score at 24 hours and age [ß-coefficient, 0.34 and 0.06]) and derived the HERMES-24 score: age (years)/10+National Institutes of Health Stroke Scale score at 24 hours. The HERMES-24 score was highly predictive for mRS ≤2 (c-statistic 0.907 [95% CI, 0.879-0.935]) in the derivation cohort. In the validation cohort and the control arm, the HERMES-24 score predicts mRS ≤2 (c-statistic, 0.914 [95% CI, 0.886-0.944] and 0.909 [95% CI, 0.887-0.930]). Observed provability of mRS ≤2 ranged between 3.1% and 3.4% when HERMES-24 score ≥25, while it ranged between 90.6% and 93.0% when HERMES-24 score <10 in the derivation cohort, validation cohort, and control arm. The HERMES-24 score also showed c-statistics of 0.894 and 0.889 for mRS ≤2 in the ESCAPE-NA1 and INTERRSeCT populations. CONCLUSIONS: The post-treatment HERMES-24 score is a simple validated score that predicts a 3-month outcome after anterior circulation large vessel occlusion stroke regardless of intervention, which helps prognostic discussion with families on day 2.


Assuntos
Procedimentos Endovasculares , AVC Isquêmico , Trombectomia , Humanos , Idoso , Feminino , Masculino , Trombectomia/métodos , Pessoa de Meia-Idade , Procedimentos Endovasculares/métodos , AVC Isquêmico/cirurgia , AVC Isquêmico/terapia , AVC Isquêmico/diagnóstico por imagem , Resultado do Tratamento , Idoso de 80 Anos ou mais , Ativador de Plasminogênio Tecidual/uso terapêutico , Prognóstico , Estudos de Coortes , Valor Preditivo dos Testes , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/cirurgia
5.
Ann Neurol ; 96(2): 321-331, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38738750

RESUMO

OBJECTIVE: For stroke patients with unknown time of onset, mismatch between diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) can guide thrombolytic intervention. However, access to MRI for hyperacute stroke is limited. Here, we sought to evaluate whether a portable, low-field (LF)-MRI scanner can identify DWI-FLAIR mismatch in acute ischemic stroke. METHODS: Eligible patients with a diagnosis of acute ischemic stroke underwent LF-MRI acquisition on a 0.064-T scanner within 24 h of last known well. Qualitative and quantitative metrics were evaluated. Two trained assessors determined the visibility of stroke lesions on LF-FLAIR. An image coregistration pipeline was developed, and the LF-FLAIR signal intensity ratio (SIR) was derived. RESULTS: The study included 71 patients aged 71 ± 14 years and a National Institutes of Health Stroke Scale of 6 (interquartile range 3-14). The interobserver agreement for identifying visible FLAIR hyperintensities was high (κ = 0.85, 95% CI 0.70-0.99). Visual DWI-FLAIR mismatch had a 60% sensitivity and 82% specificity for stroke patients <4.5 h, with a negative predictive value of 93%. LF-FLAIR SIR had a mean value of 1.18 ± 0.18 <4.5 h, 1.24 ± 0.39 4.5-6 h, and 1.40 ± 0.23 >6 h of stroke onset. The optimal cut-point for LF-FLAIR SIR was 1.15, with 85% sensitivity and 70% specificity. A cut-point of 6.6 h was established for a FLAIR SIR <1.15, with an 89% sensitivity and 62% specificity. INTERPRETATION: A 0.064-T portable LF-MRI can identify DWI-FLAIR mismatch among patients with acute ischemic stroke. Future research is needed to prospectively validate thresholds and evaluate a role of LF-MRI in guiding thrombolysis among stroke patients with uncertain time of onset. ANN NEUROL 2024;96:321-331.


Assuntos
Imagem de Difusão por Ressonância Magnética , AVC Isquêmico , Humanos , Idoso , Masculino , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , AVC Isquêmico/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
6.
Lancet ; 403(10444): 2597-2605, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38768626

RESUMO

BACKGROUND: Individuals with minor ischaemic stroke and intracranial occlusion are at increased risk of poor outcomes. Intravenous thrombolysis with tenecteplase might improve outcomes in this population. We aimed to test the superiority of intravenous tenecteplase over non-thrombolytic standard of care in patients with minor ischaemic stroke and intracranial occlusion or focal perfusion abnormality. METHODS: In this multicentre, prospective, parallel group, open label with blinded outcome assessment, randomised controlled trial, adult patients (aged ≥18 years) were included at 48 hospitals in Australia, Austria, Brazil, Canada, Finland, Ireland, New Zealand, Singapore, Spain, and the UK. Eligible patients with minor acute ischaemic stroke (National Institutes of Health Stroke Scale score 0-5) and intracranial occlusion or focal perfusion abnormality were enrolled within 12 h from stroke onset. Participants were randomly assigned (1:1), using a minimal sufficient balance algorithm to intravenous tenecteplase (0·25 mg/kg) or non-thrombolytic standard of care (control). Primary outcome was a return to baseline functioning on pre-morbid modified Rankin Scale score in the intention-to-treat (ITT) population (all patients randomly assigned to a treatment group and who did not withdraw consent to participate) assessed at 90 days. Safety outcomes were reported in the ITT population and included symptomatic intracranial haemorrhage and death. This trial is registered with ClinicalTrials.gov, NCT02398656, and is closed to accrual. FINDINGS: The trial was stopped early for futility. Between April 27, 2015, and Jan 19, 2024, 886 patients were enrolled; 369 (42%) were female and 517 (58%) were male. 454 (51%) were assigned to control and 432 (49%) to intravenous tenecteplase. The primary outcome occurred in 338 (75%) of 452 patients in the control group and 309 (72%) of 432 in the tenecteplase group (risk ratio [RR] 0·96, 95% CI 0·88-1·04, p=0·29). More patients died in the tenecteplase group (20 deaths [5%]) than in the control group (five deaths [1%]; adjusted hazard ratio 3·8; 95% CI 1·4-10·2, p=0·0085). There were eight (2%) symptomatic intracranial haemorrhages in the tenecteplase group versus two (<1%) in the control group (RR 4·2; 95% CI 0·9-19·7, p=0·059). INTERPRETATION: There was no benefit and possible harm from treatment with intravenous tenecteplase. Patients with minor stroke and intracranial occlusion should not be routinely treated with intravenous thrombolysis. FUNDING: Heart and Stroke Foundation of Canada, Canadian Institutes of Health Research, and the British Heart Foundation.


Assuntos
Fibrinolíticos , AVC Isquêmico , Tenecteplase , Humanos , Tenecteplase/uso terapêutico , Tenecteplase/administração & dosagem , Masculino , Feminino , AVC Isquêmico/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Fibrinolíticos/administração & dosagem , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , Estudos Prospectivos , Padrão de Cuidado , Ativador de Plasminogênio Tecidual/uso terapêutico , Ativador de Plasminogênio Tecidual/administração & dosagem , Terapia Trombolítica/métodos
7.
Int J Stroke ; 19(7): 817-822, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38676572

RESUMO

BACKGROUND: Almost half of acute ischemic stroke patients present with mild symptoms and there are large practice variations in their treatment globally. Individuals with an intracranial occlusion who present with minor stroke are at an increased risk of early neurological deterioration and poor outcomes. Individual patient data meta-analysis in the subgroup of patients with minor deficits showed benefit of alteplase in improving outcomes; however, this benefit has not been seen with intravenous alteplase in published randomized trials. DESIGN: TEMPO-2 (A Randomized Controlled Trial of Tenecteplase Versus Standard of Care for Minor Ischemic Stroke With Proven Occlusion) is a prospective, open label with blinded outcome assessment, randomized controlled trial, designed to test the superiority of intravenous tenecteplase (0.25 mg/kg) over nonthrombolytic standard of care, with an estimated sample size of 1274 patients. Adult patients presenting with acute ischemic stroke with the National Institutes of Health Stroke Scale (NIHSS) ⩽ 5 and visible arterial occlusion or perfusion deficit within 12 h of onset are randomized to receive either tenecteplase (0.25 mg/kg) or standard of care. The primary outcome is return to baseline neurological functioning, measured by the modified Rankin scale (mRS) at 90 days. Safety outcomes include death and symptomatic hemorrhage (intra or extra-cranial). Other secondary outcomes include mRS 0-1, mRS 0-2, ordinal shift analysis of the mRS, partial, and full recanalization on follow-up computed tomography angiogram. CONCLUSION: Results of this trial will aid in determining whether there is benefit of using tenecteplase (0.25 mg/kg) in treating patients presenting with minor stroke who are at high risk of developing poor outcomes due to presence of an intracranial occlusion. DATA ACCESS STATEMENT: Data will be available upon reasonable request.


Assuntos
Fibrinolíticos , AVC Isquêmico , Tenecteplase , Humanos , Tenecteplase/uso terapêutico , Tenecteplase/administração & dosagem , AVC Isquêmico/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Fibrinolíticos/administração & dosagem , Padrão de Cuidado , Masculino , Resultado do Tratamento , Feminino , Estudos Prospectivos , Ativador de Plasminogênio Tecidual/uso terapêutico , Ativador de Plasminogênio Tecidual/administração & dosagem , Idoso , Pessoa de Meia-Idade
8.
Int J Stroke ; 19(8): 935-941, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38676549

RESUMO

INTRODUCTION: Lacunar stroke represents around a quarter of all ischemic strokes; however, their identification with computed tomography in the hyperacute setting is challenging. We aimed to validate a clinical score to identify lacunar stroke in the acute setting, independently, with data from the WAKE-UP trial using magnetic resonance imaging. METHODS: We analyzed data from the WAKE-UP trial and extracted Oxfordshire Community Stroke Project (OCSP) classification. Lacunar score was defined by National Institutes of Health Stroke Scale (NIHSS) < 7 and OCSP lacunar syndrome. Assessment of lacunar infarct by two independent investigators was blinded to clinical data. We calculated sensitivity, specificity, negative and positive predictive value (NPV and PPV, respectively) of lacunar score. RESULTS: We included 503 patients in the analysis, mean (±SD) age 65.2 (±11.6) years, 325 (65%) males, median (IQR) NIHSS = 6 (4-9); 108 (22%) lacunar infarcts were identified on magnetic resonance (MR), patients fulfilling lacunar score criteria were 120 (24%), of which 47 (44%) had a lacunar infarct. Lacunar score was negative in 322 (82%) of patients without lacunar infarct. Patients with lacunar score had lower NIHSS (4 vs 7, p < 0.001), higher systolic (157 vs 151 mmHg, p = 0.001) and diastolic (86 vs 83 mmHg, p = 0.013) blood pressure and smaller infarct volume (2.4 vs 9.5 mL, p < 0.001). Performance of lacunar score was as follows: sensitivity 0.44; specificity 0.82; PPV 0.39; NPV 0.84; and accuracy 0.73. Assuming a prevalence of lacunar stroke of 13%, PPV lowered to 0.30 but NPV was 0.90. Lacunar score performed better for supratentorial lacunar infarcts. CONCLUSION: Lacunar score had a very good specificity and NPV for screening of lacunar stroke. Implementation of this simple tool into clinical practice may help hyperacute management and guide patient selection in clinical trials. DATA ACCESS STATEMENT: Data supporting the results of this paper are available upon reasonable request to the corresponding author.


Assuntos
Imageamento por Ressonância Magnética , Acidente Vascular Cerebral Lacunar , Humanos , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem , Acidente Vascular Cerebral Lacunar/diagnóstico , Masculino , Feminino , Idoso , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Valor Preditivo dos Testes
9.
Stroke ; 55(4): 866-873, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38440891

RESUMO

BACKGROUND: Ischemic stroke lesion volume at follow-up is an important surrogate outcome for acute stroke trials. We aimed to assess which differences in 48-hour lesion volume translate into meaningful clinical differences. METHODS: We used pooled data from 7 trials investigating the efficacy of endovascular treatment for anterior circulation large vessel occlusion in acute ischemic stroke. We assessed 48-hour lesion volume follow-up computed tomography or magnetic resonance imaging. The primary outcome was a good functional outcome, defined as modified Rankin Scale (mRS) scores of 0 to 2. We performed multivariable logistic regression to predict the probability of achieving mRS scores of 0 to 2 and determined the differences in 48-hour lesion volume that correspond to a change of 1%, 5%, and 10% in the adjusted probability of achieving mRS scores of 0 to 2. RESULTS: In total, 1665/1766 (94.2%) patients (median age, 68 [interquartile range, 57-76] years, 781 [46.9%] female) had information on follow-up ischemic lesion volume. Computed tomography was used for follow-up imaging in 83% of patients. The median 48-hour lesion volume was 41 (interquartile range, 14-120) mL. We observed a linear relationship between 48-hour lesion volume and mRS scores of 0 to 2 for adjusted probabilities between 65% and 20%/volumes <80 mL, although the curve sloped off for lower mRS scores of 0-2 probabilities/higher volumes. The median differences in 48-hour lesion volume associated with a 1%, 5%, and 10% increase in the probability of mRS scores of 0 to 2 for volumes <80 mL were 2 (interquartile range, 2-3), 10 (9-11), and 20 (18-23) mL, respectively. We found comparable associations when assessing computed tomography and magnetic resonance imaging separately. CONCLUSIONS: A difference of 2, 10, and 20 mL in 48-hour lesion volume, respectively, is associated with a 1%, 5%, and 10% absolute increase in the probability of achieving good functional outcome. These results can inform the design of future stroke trials that use 48-hour lesion volume as the primary outcome.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , Idoso , Masculino , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/tratamento farmacológico , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X/métodos , Infarto , Resultado do Tratamento , Procedimentos Endovasculares/métodos , Isquemia Encefálica/terapia , Isquemia Encefálica/tratamento farmacológico
10.
J Hum Hypertens ; 38(4): 307-313, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38438602

RESUMO

Blood Pressure Variability (BPV) is associated with cardiovascular risk and serum uric acid level. We investigated whether BPV was lowered by allopurinol and whether it was related to neuroimaging markers of cerebral small vessel disease (CSVD) and cognition. We used data from a randomised, double-blind, placebo-controlled trial of two years allopurinol treatment after recent ischemic stroke or transient ischemic attack. Visit-to-visit BPV was assessed using brachial blood pressure (BP) recordings. Short-term BPV was assessed using ambulatory BP monitoring (ABPM) performed at 4 weeks and 2 years. Brain MRI was performed at baseline and 2 years. BPV measures were compared between the allopurinol and placebo groups, and with CSVD and cognition. 409 participants (205 allopurinol; 204 placebo) were included in the visit-to-visit BPV analyses. There were no significant differences found between placebo and allopurinol groups for any measure of visit-to-visit BPV. 196 participants were included in analyses of short-term BPV at week 4. Two measures were reduced by allopurinol: the standard deviation (SD) of systolic BP (by 1.30 mmHg (95% confidence interval (CI) 0.18-2.42, p = 0.023)); and the average real variability (ARV) of systolic BP (by 1.31 mmHg (95% CI 0.31-2.32, p = 0.011)). There were no differences in other measures at week 4 or in any measure at 2 years, and BPV was not associated with CSVD or cognition. Allopurinol treatment did not affect visit-to-visit BPV in people with recent ischemic stroke or TIA. Two BPV measures were reduced at week 4 by allopurinol but not at 2 years.


Assuntos
Hipertensão , Ataque Isquêmico Transitório , AVC Isquêmico , Humanos , Pressão Sanguínea , Ataque Isquêmico Transitório/diagnóstico por imagem , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/etiologia , Alopurinol/uso terapêutico , AVC Isquêmico/complicações , AVC Isquêmico/tratamento farmacológico , Ácido Úrico , Fatores de Risco , Monitorização Ambulatorial da Pressão Arterial
11.
Trials ; 25(1): 150, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38419030

RESUMO

BACKGROUND: Recruitment of participants is the greatest risk to completion of most clinical trials, with 20-40% of trials failing to reach the targeted enrollment. This is particularly true of trials of central nervous system (CNS) therapies such as intervention for chronic stroke. The PISCES III trial was an invasive trial of stereotactically guided intracerebral injection of CTX0E03, a fetal derived neural stem cell line, in patients with chronic disability due to ischemic stroke. We report on the experience using a novel hybrid recruitment approach of a patient-facing portal to self-identify and perform an initial screen for general trial eligibility (tier 1), followed by phone screening and medical records review (tier 2) prior to a final in-person visit to confirm eligibility and consent. METHODS: Two tiers of screening were established: an initial screen of general eligibility using a patient-facing web portal (tier 1), followed by a more detailed screen that included phone survey and medical record review (tier 2). If potential participants passed the tier 2 screen, they were referred directly to visit 1 at a study site, where final in-person screening and consent were performed. Rates of screening were tracked during the period of trial recruitment and sources of referrals were noted. RESULTS: The approach to screening and recruitment resulted in 6125 tier 1 screens, leading to 1121 referrals to tier 2. The tier 2 screening resulted in 224 medical record requests and identification of 86 qualifying participants for referral to sites. The study attained a viable recruitment rate of 6 enrolled per month prior to being disrupted by COVID 19. CONCLUSIONS: A tiered approach to eligibility screening using a hybrid of web-based portals to self-identify and screen for general eligibility followed by a more detailed phone and medical record review allowed the study to use fewer sites and reduce cost. Despite the difficult and narrow population of patients suffering moderate chronic disability from stroke, this strategy produced a viable recruitment rate for this invasive study of intracranially injected neural stem cells. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03629275.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Seleção de Pacientes , Projetos de Pesquisa , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Prontuários Médicos
12.
J Stroke Cerebrovasc Dis ; 33(1): 107512, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38007987

RESUMO

BACKGROUND: The extent and distribution of intracranial hemorrhage (ICH) directly affects clinical management. Artificial intelligence (AI) software can detect and may delineate ICH extent on brain CT. We evaluated e-ASPECTS software (Brainomix Ltd.) performance for ICH delineation. METHODS: We qualitatively assessed software delineation of ICH on CT using patients from six stroke trials. We assessed hemorrhage delineation in five compartments: lobar, deep, posterior fossa, intraventricular, extra-axial. We categorized delineation as excellent, good, moderate, or poor. We assessed quality of software delineation with number of affected compartments in univariate analysis (Kruskall-Wallis test) and ICH location using logistic regression (dependent variable: dichotomous delineation categories 'excellent-good' versus 'moderate-poor'), and report odds ratios (OR) and 95 % confidence intervals (95 %CI). RESULTS: From 651 patients with ICH (median age 75 years, 53 % male), we included 628 with assessable CTs. Software delineation of ICH extent was 'excellent' in 189/628 (30 %), 'good' in 255/628 (41 %), 'moderate' in 127/628 (20 %), and 'poor' in 57/628 cases (9 %). The quality of software delineation of ICH was better when fewer compartments were affected (Z = 3.61-6.27; p = 0.0063). Software delineation of ICH extent was more likely to be 'excellent-good' quality when lobar alone (OR = 1.56, 95 %CI = 0.97-2.53) but 'moderate-poor' with any intraventricular (OR = 0.56, 95 %CI = 0.39-0.81, p = 0.002) or any extra-axial (OR = 0.41, 95 %CI = 0.27-0.62, p<0.001) extension. CONCLUSIONS: Delineation of ICH extent on stroke CT scans by AI software was excellent or good in 71 % of cases but was more likely to over- or under-estimate extent when ICH was either more extensive, intraventricular, or extra-axial.


Assuntos
Hemorragia Cerebral , Acidente Vascular Cerebral , Humanos , Masculino , Idoso , Feminino , Hemorragia Cerebral/diagnóstico por imagem , Inteligência Artificial , Acidente Vascular Cerebral/diagnóstico por imagem , Hemorragias Intracranianas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Software , Neuroimagem
13.
Stroke Vasc Neurol ; 9(1): 38-49, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-37290930

RESUMO

BACKGROUND: The effect of transdermal glyceryl trinitrate (GTN, a nitrovasodilator) on clinical outcome when administered before hospital admission in suspected stroke patients is unclear. Here, we assess the safety and efficacy of GTN in the prespecified subgroup of patients who had an ischaemic stroke within the Rapid Intervention with Glyceryl trinitrate in Hypertensive stroke Trial-2 (RIGHT-2). METHODS: RIGHT-2 was an ambulance-based multicentre sham-controlled blinded-endpoint study with patients randomised within 4 hours of onset. The primary outcome was a shift in scores on the modified Rankin scale (mRS) at day 90. Secondary outcomes included death; a global analysis (Wei-Lachin test) containing Barthel Index, EuroQol-5D, mRS, telephone interview for cognitive status-modified and Zung depression scale; and neuroimaging-determined 'brain frailty' markers. Data were reported as n (%), mean (SD), median [IQR], adjusted common OR (acOR), mean difference or Mann-Whitney difference (MWD) with 95% CI. RESULTS: 597 of 1149 (52%) patients had a final diagnosis of ischaemic stroke; age 75 (12) years, premorbid mRS>2 107 (18%), Glasgow Coma Scale 14 (2) and time from onset to randomisation 67 [45, 108] min. Neuroimaging 'brain frailty' was common: median score 2 [2, 3] (range 0-3). At day 90, GTN did not influence the primary outcome (acOR for increased disability 1.15, 95% CI 0.85 to 1.54), death or global analysis (MWD 0.00, 95% CI -0.10 to 0.09). In subgroup analyses, there were non-significant interactions suggesting GTN may be associated with more death and dependency in participants randomised within 1 hour of symptom onset and in those with more severe stroke. CONCLUSIONS: In patients who had an ischaemic stroke, ultra-acute administration of transdermal GTN in the ambulance did not improve clinical outcomes in a population with more clinical and radiological frailty than seen in previous in-hospital trials.


Assuntos
Isquemia Encefálica , Fragilidade , Hipertensão , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Idoso , Nitroglicerina/efeitos adversos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Ambulâncias , Fragilidade/induzido quimicamente , Fragilidade/complicações , Hipertensão/complicações , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/tratamento farmacológico
14.
Lancet Neurol ; 22(11): 991-1004, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37863608

RESUMO

BACKGROUND: Hypertension is the leading risk factor for cerebral small vessel disease. We aimed to determine whether antihypertensive drug classes differentially affect microvascular function in people with small vessel disease. METHODS: We did a multicentre, open-label, randomised crossover trial with blinded endpoint assessment at five specialist centres in Europe. We included participants aged 18 years or older with symptomatic sporadic small vessel disease or cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and an indication for antihypertensive treatment. Participants were randomly assigned (1:1:1) to one of three sequences of antihypertensive treatment using a computer-generated multiblock randomisation, stratified by study site and patient group. A 2-week washout period was followed by three 4-week periods of oral monotherapy with amlodipine, losartan, or atenolol at approved doses. The primary endpoint was change in cerebrovascular reactivity (CVR) determined by blood oxygen level-dependent MRI response to hypercapnic challenge in normal-appearing white matter from the end of washout to the end of each treatment period. Efficacy analyses were done by intention-to-treat principles in all randomly assigned participants who had at least one valid assessment for the primary endpoint, and analyses were done separately for participants with sporadic small vessel disease and CADASIL. This trial is registered at ClinicalTrials.gov, NCT03082014, and EudraCT, 2016-002920-10, and is terminated. FINDINGS: Between Feb 22, 2018, and April 28, 2022, 75 participants with sporadic small vessel disease (mean age 64·9 years [SD 9·9]) and 26 with CADASIL (53·1 years [7·0]) were enrolled and randomly assigned to treatment. 79 participants (62 with sporadic small vessel disease and 17 with CADASIL) entered the primary efficacy analysis. Change in CVR did not differ between study drugs in participants with sporadic small vessel disease (mean change in CVR 1·8 × 10-4%/mm Hg [SE 20·1; 95% CI -37·6 to 41·2] for amlodipine; 16·7 × 10-4%/mm Hg [20·0; -22·3 to 55·8] for losartan; -7·1 × 10-4%/mm Hg [19·6; -45·5 to 31·1] for atenolol; poverall=0·39) but did differ in patients with CADASIL (15·7 × 10-4%/mm Hg [SE 27·5; 95% CI -38·3 to 69·7] for amlodipine; 19·4 × 10-4%/mm Hg [27·9; -35·3 to 74·2] for losartan; -23·9 × 10-4%/mm Hg [27·5; -77·7 to 30·0] for atenolol; poverall=0·019). In patients with CADASIL, pairwise comparisons showed that CVR improved with amlodipine compared with atenolol (-39·6 × 10-4%/mm Hg [95% CI -72·5 to -6·6; p=0·019) and with losartan compared with atenolol (-43·3 × 10-4%/mm Hg [-74·3 to -12·3]; p=0·0061). No deaths occurred. Two serious adverse events were recorded, one while taking amlodipine (diarrhoea with dehydration) and one while taking atenolol (fall with fracture), neither of which was related to study drug intake. INTERPRETATION: 4 weeks of treatment with amlodipine, losartan, or atenolol did not differ in their effects on cerebrovascular reactivity in people with sporadic small vessel disease but did result in differential treatment effects in patients with CADASIL. Whether antihypertensive drug classes differentially affect clinical outcomes in people with small vessel diseases requires further research. FUNDING: EU Horizon 2020 programme.


Assuntos
CADASIL , Hipertensão , Humanos , Pessoa de Meia-Idade , Idoso , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Losartan/farmacologia , Losartan/uso terapêutico , Atenolol/farmacologia , Atenolol/uso terapêutico , CADASIL/tratamento farmacológico , Estudos Cross-Over , Resultado do Tratamento , Hipertensão/tratamento farmacológico , Anlodipino/farmacologia , Anlodipino/uso terapêutico , Método Duplo-Cego
15.
J Neurol Sci ; 452: 120743, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37531792

RESUMO

BACKGROUND: Intracerebral haemorrhage (ICH) is a severe clinical consequence of cerebral small vessel disease (SVD), but associations between renal impairment and SVD in patients with ICH have not been fully characterised. METHODS: Using data from the CROMIS-2 ICH observational study, we compared SVD neuroimaging markers and total burden (score 0-3) identified using CT brain imaging in patients with and without renal impairment (estimated glomerular filtration rate, eGFR<60). We assessed functional outcome at 6-month follow-up using the modified Rankin scale. RESULTS: 1027 participants were included (mean age 72.8, 57.1% male); 274 with and 753 without renal impairment. 18.7% of the eGFR<60 group had moderate-to-severe SVD burden (score 2-3), compared with 14.0% of those with eGFR>60 (p = 0.039). SVD burden was associated with renal impairment after adjusting for hypertension (OR 1.36, 95% CI 1.04-1.77, p = 0.023), but not after adjusting for age. Cerebral atrophy was more prevalent in patients with eGFR<60 (81.2% vs. 72.0%, p = 0.002), as were WMH (45.6% vs. 36.6%, p = 0.026). Neither was associated with renal function after adjusting for age and vascular risk factors. Renal impairment was associated with functional outcome (OR 0.65, 95% CI 0.47-0.89, p = 0.007), but not after adjusting for age, pre-morbid function and comorbidities (OR 0.95, 95% CI 0.65-1.38, p = 0.774). CONCLUSION: In acute ICH, renal impairment is associated with a higher cerebral SVD burden independent of hypertension, but not age. Reduced eGFR is associated with worse functional outcome, but not independent of age and comorbidities. Since CT has limited sensitivity to detect SVD severity and distribution, further studies including MRI are needed.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Hipertensão , Humanos , Masculino , Feminino , Estudos Prospectivos , Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/epidemiologia , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Imageamento por Ressonância Magnética , Hipertensão/complicações , Rim/diagnóstico por imagem , Rim/fisiologia
16.
J Neurointerv Surg ; 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532454

RESUMO

BACKGROUND: Functional outcomes in patients with acute ischemic stroke (AIS) with large vessel occlusion (LVO) undergoing endovascular treatment (EVT) with poor reperfusion were compared with patients with AIS-LVO treated with best medical management only. METHODS: Data are from the HERMES collaboration, a patient-level meta-analysis of seven randomized EVT trials. Baseline characteristics and functional outcomes (modified Rankin Scale (mRS) score at 90 days) were compared between patients with poor reperfusion (defined as modified Thrombolysis in Cerebral Infarction Score 0-1 on the final intracranial angiography run as assessed by the central imaging core laboratory) and patients in the control arm with multivariable logistic ordinal logistic regression adjusted for pre-specified baseline variables. RESULTS: 972 of 1764 patients from the HERMES collaboration were included in the analysis: 893 in the control arm and 79 in the EVT arm with final mTICI 0-1. Patients with poor reperfusion who underwent EVT had higher baseline National Institutes of Health Stroke Scale than controls (median 19 (IQR 15.5-21) vs 17 (13-21), P=0.011). They also had worse mRS at 90 days compared with those in the control arm in adjusted analysis (median 4 (IQR 3-6) vs median 4 (IQR 2-5), adjusted common OR 0.59 (95% CI 0.38 to 0.91)). Symptomatic intracranial hemorrhage was not different between the two groups (3.9% vs 3.5%, P=0.75, adjusted OR 0.94 (95% CI 0.23 to 3.88)). CONCLUSION: Poor reperfusion after EVT was associated with worse outcomes than best medical management, although no difference in symptomatic intracranial hemorrhage was seen. These results emphasize the need for additional efforts to further improve technical EVT success rates.

17.
BMJ Neurol Open ; 5(1): e000424, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37564156

RESUMO

Background: The Rapid Intervention with Glyceryl Trinitrate in Hypertensive Stroke Trial-2 (RIGHT-2) reported no overall treatment difference between glyceryl trinitrate (GTN) and sham at day 90. Here we assess participants' outcomes 1 year after randomisation. Methods: RIGHT-2 was an ambulance-based prospective randomised controlled trial where patients with presumed stroke and systolic blood pressure (BP) of >120 mm Hg received either GTN (5 mg/day) or sham patch. Centralised blinded telephone follow-up was performed at days 90 (primary endpoint) and 365 (secondary endpoint). The lead outcome was dependency assessed with the modified Rankin Scale (mRS). Results: 1149 patients were recruited to RIGHT-2 between October 2015 and May 2018, and 1097 (95.5%) had outcome data recorded at day 365. At baseline, the patients were; female (48%), had a mean age of 73 (15) years, BP of 162 (25)/92 (18) mm Hg, onset to randomisation of 70 (45-115) min, diagnosis of ischaemic stroke (52%), intracerebral haemorrhage (ICH) (13%), transient ischaemic attack (TIA) (9%) and mimics (26%). There was no effect of GTN on mRS score at day 365 in participants with confirmed stroke/TIA (adjusted common odds ratio (acOR) 1.10, 95% CI 0.86 to 1.42) or in all patients. In patients randomised to GTN, mRS at day 365 tended to be worse in those with ICH (acOR 1.65, 95% CI 0.84 to 3.25) and better in those with a mimic diagnosis (acOR 0.53, 95% CI 0.33 to 0.84). Conclusion: At 1 year post randomisation, dependency did not differ between GTN and sham treatment in either the target population or overall. In prespecified subgroup analyses, GTN was associated with reduced dependency in participants with a final diagnosis of mimic and a non-significant worse outcome in participants with ICH. Trial registration number: ISRCTN26986053.

18.
Eur Stroke J ; 8(3): 819-827, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37452707

RESUMO

PURPOSE: Recombinant human interleukin-1 receptor antagonist (anakinra) is an anti-inflammatory with efficacy in animal models of stroke. We tested the effect of anakinra on perihaematomal oedema in acute intracerebral haemorrhage (ICH) and explored effects on inflammatory markers. METHODS: We conducted a multicentre, randomised, double-blind, placebo-controlled trial in patients with acute, spontaneous, supratentorial ICH between May 2019 and February 2021. Patients were randomised to 100 mg subcutaneous anakinra within 8 h of onset, followed by five, 12-hourly, 100 mg subcutaneous injections, or matched placebo. Primary outcome was oedema extension distance (OED) on a 72 h CT scan. Secondary outcomes included plasma C-reactive protein (CRP) and interleukin-6 (IL-6). FINDINGS: 25 patients (target = 80) were recruited, 14 randomised to anakinra, 11 to placebo. Mean age was 67 and 52% were male. The anakinra group had higher median baseline ICH volume (12.6 ml, interquartile range[IQR]:4.8-17.9) versus placebo (5.5 ml, IQR:2.1-10.9). Adjusting for baseline, 72 h OED was not significantly different between groups (mean difference OED anakinra vs placebo -0.05 cm, 95% confidence interval [CI]: -0.17-0.06, p = 0.336). There was no significant difference in area-under-the-curve to Day 4 for IL-6 and CRP, but a post-hoc analysis demonstrated IL-6 was 56% (95% CI: 2%-80%) lower at Day 2 with anakinra. There were 10 and 2 serious adverse events in anakinra and placebo groups, respectively, none attributed to anakinra. CONCLUSION: We describe feasibility for delivering anakinra in acute ICH and provide preliminary safety data. We lacked power to test for effects on oedema thus further trials will be required.


Assuntos
Citocinas , Proteína Antagonista do Receptor de Interleucina 1 , Humanos , Masculino , Idoso , Feminino , Proteína Antagonista do Receptor de Interleucina 1/efeitos adversos , Citocinas/uso terapêutico , Interleucina-6/uso terapêutico , Hemorragia Cerebral/tratamento farmacológico , Inibidores de Interleucina , Receptores de Interleucina-1 , Interleucina-1
19.
JAMA Neurol ; 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37523199

RESUMO

Importance: Outcome prediction after endovascular treatment (EVT) for ischemic stroke is important to patients, family members, and physicians. Objective: To develop and validate a model based on preprocedural and postprocedural characteristics to predict functional outcome for individual patients after EVT. Design, Setting, and Participants: A prediction model was developed using individual patient data from 7 randomized clinical trials, performed between December 2010 and December 2014. The model was developed within the Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials (HERMES) collaboration and external validation in data from the Dutch Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) Registry of patients treated in clinical practice between March 2014 and November 2017. Participants included patients from multiple centers throughout different countries in Europe, North America, East Asia, and Oceania (derivation cohort), and multiple centers in the Netherlands (validation cohort). Included were adult patients with a history of ischemic stroke from an intracranial large vessel occlusion in the anterior circulation who underwent EVT within 12 hours of symptom onset or last seen well. Data were last analyzed in July 2022. Main Outcome(s) and Measure(s): A total of 19 variables were assessed by multivariable ordinal regression to predict functional outcome (modified Rankin Scale [mRS] score) 90 days after EVT. Variables were routinely available 1 day after EVT. Akaike information criterion (AIC) was used to optimize model fit vs model complexity. Probabilities for functional independence (mRS 0-2) and survival (mRS 0-5) were derived from the ordinal model. Model performance was expressed with discrimination (C statistic) and calibration. Results: A total of 781 patients (median [IQR] age, 67 [57-76] years; 414 men [53%]) constituted the derivation cohort, and 3260 patients (median [IQR] age, 72 [61-80] years; 1684 men [52%]) composed the validation cohort. Nine variables were included in the model: age, baseline National Institutes of Health Stroke Scale (NIHSS) score, prestroke mRS score, history of diabetes, occlusion location, collateral score, reperfusion grade, NIHSS score at 24 hours, and symptomatic intracranial hemorrhage 24 hours after EVT. External validation in the MR CLEAN Registry showed excellent discriminative ability for functional independence (C statistic, 0.91; 95% CI, 0.90-0.92) and survival (0.89; 95% CI, 0.88-0.90). The proportion of functional independence in the MR CLEAN Registry was systematically higher than predicted by the model (41% vs 34%), whereas observed and predicted survival were similar (72% vs 75%). The model was updated and implemented for clinical use. Conclusion and relevance: The prognostic tool MR PREDICTS@24H can be applied 1 day after EVT to accurately predict functional outcome for individual patients at 90 days and to provide reliable outcome expectations and personalize follow-up and rehabilitation plans. It will need further validation and updating for contemporary patients.

20.
Front Digit Health ; 5: 1186516, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37388253

RESUMO

Introduction: Thrombolysis treatment for acute ischaemic stroke can lead to better outcomes if administered early enough. However, contraindications exist which put the patient at greater risk of a bleed (e.g. recent major surgery, anticoagulant medication). Therefore, clinicians must check a patient's past medical history before proceeding with treatment. In this work we present a machine learning approach for accurate automatic detection of this information in unstructured text documents such as discharge letters or referral letters, to support the clinician in making a decision about whether to administer thrombolysis. Methods: We consulted local and national guidelines for thrombolysis eligibility, identifying 86 entities which are relevant to the thrombolysis decision. A total of 8,067 documents from 2,912 patients were manually annotated with these entities by medical students and clinicians. Using this data, we trained and validated several transformer-based named entity recognition (NER) models, focusing on transformer models which have been pre-trained on a biomedical corpus as these have shown most promise in the biomedical NER literature. Results: Our best model was a PubMedBERT-based approach, which obtained a lenient micro/macro F1 score of 0.829/0.723. Ensembling 5 variants of this model gave a significant boost to precision, obtaining micro/macro F1 of 0.846/0.734 which approaches the human annotator performance of 0.847/0.839. We further propose numeric definitions for the concepts of name regularity (similarity of all spans which refer to an entity) and context regularity (similarity of all context surrounding mentions of an entity), using these to analyse the types of errors made by the system and finding that the name regularity of an entity is a stronger predictor of model performance than raw training set frequency. Discussion: Overall, this work shows the potential of machine learning to provide clinical decision support (CDS) for the time-critical decision of thrombolysis administration in ischaemic stroke by quickly surfacing relevant information, leading to prompt treatment and hence to better patient outcomes.

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