Search

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. [ABSTRACT FROM AUTHOR]

Author(s): Ryan F. Maguire [a]; Daniel J. Wilkinson [a]; Timothy J. England [a,b]; Saoirse E. O'Sullivan [a,c] Introduction Preclinical and early clinical phase studies demonstrate the potential of cannabidiol (CBD) [...], Introduction: Cannabidiol (CBD) can be isolated from Cannabis sativa L. or synthetically produced. The aim of this study was to compare the in vitro effects of purified natural and synthetic CBD to establish any pharmacological differences or superiority between sources. Methods: Six purified samples of CBD were obtained, 4 of these were natural and 2 synthetic. The anticancer effects of CBD were assessed in a human ovarian cancer cell line (SKOV-3 cells). The neuroprotective effects of CBD were assessed in human pericytes in a model of stroke (oxygen glucose deprivation [OGD]). The ability of CBD to restore inflammation-induced intestinal permeability was assessed in differentiated human Caco-2 cells (a model of enterocytes). Results: (1) In proliferating and confluent SKOV-3 cells, all CBD samples similarly reduced resazurin metabolism as a marker of cell viability in a concentration-dependent manner (p < 0.001). (2) In pericytes exposed to OGD, all CBD samples similarly reduced cellular damage (measured by lactate dehydrogenase) at 24 h by 31-48% and reduced inflammation (measured by IL-6 secretion) by 30-53%. Attenuation of IL-6 was inhibited by 5HT[sub.1A] receptor antagonism for all CBD sources. (3) In differentiated Caco-2 cells exposed to inflammation (TNF[alpha] and IFN[gamma], 10 ng/mL for 24 h), each CBD sample increased the speed of recovery of epithelial permeability compared to control (p < 0.05-0.001), which was inhibited by a CB[sub.1] receptor antagonist. Conclusion: Our results suggest that there is no pharmacological difference in vitro in the antiproliferative, anti-inflammatory, or permeability effects of purified natural versus synthetic CBD. The purity and reliability of CBD samples, as well as the ultimate pharmaceutical preparation, should all be considered above the starting source of CBD in the development of new CBD medicines. Keywords: Cannabidiol, Synthetic cannabidiol, Plant, Pharmacology, Cannabinoid receptor 1, 5HT.sub.1A

Remote ischemic conditioning (RIC) is the application of brief periods of ischemia to an organ or tissue with the aim of inducing protection from ischemia in a distant organ. It was first developed as a cardioprotective strategy but has been increasingly investigated as a neuroprotective intervention. The mechanisms by which RIC achieves neuroprotection are incompletely understood. Preclinical studies focus on the hypothesis that RIC can protect the brain from ischemia reperfusion (IR) injury following the restoration of blood flow after occlusion of a large cerebral artery. However, increasingly, a role of chronic RIC (CRIC) is being investigated as a means of promoting recovery following an ischemic insult to the brain. The recent publication of two large, randomized control trials has provided promise that RIC could improve functional outcomes after acute ischemic stroke, and that there may be a role for CRIC in the prevention of recurrent stroke. Although less developed, there is also proof-of-concept to suggest that RIC may be used to reduce vasospasm after subarachnoid hemorrhage or improve cognitive outcomes in vascular dementia. As a cheap, well-tolerated and almost universally applicable intervention, the motivation for investigating possible benefit of RIC in patients with cerebrovascular disease is great. In this review, we shall review the current evidence for RIC as applied to cerebrovascular disease. [ABSTRACT FROM AUTHOR]

Background There is a paucity of data on anesthesia-related outcomes for endovascular treatment (EVT) in the extended window (>6 hours from ischemic stroke onset). We compared functional and safety outcomes between local anesthesia (LA) without sedation, conscious sedation (CS) and general anesthesia (GA). Methods Patients who underwent EVT in the early (<6 hours) and extended time windows using LA, CS, or GA between October 2015 and March 2020 were included from a UK national stroke registry. Multivariable analyses were performed, adjusted for age, sex, baseline stroke severity, pre-stroke disability, EVT technique, center, procedural time and IV thrombolysis. Results A total of 4337 patients were included, 3193 in the early window (1135 LA, 446 CS, 1612 GA) and 1144 in the extended window (357 LA, 134 CS, 653 GA). Compared with GA, patients treated under LA alone had increased odds of an improved modified Rankin Scale (mRS) score at discharge (early: adjusted common (ac) 0R=1.50, 95% CI 1.29 to 1.74, p=0.001; extended: acOR=1.29, 95% CI 1.01 to 1.66, p=0.043). Similar mRS scores at discharge were found in the LA and CS cohorts in the early and extended windows (p=0.21). Compared with CS, use of GA was associated with a worse mRS score at discharge in the early window (acOR=0.73, 95% CI 0.45 to 0.96, p=0.017) but not in the extended window (p=0.55). There were no significant differences in the rates of symptomatic intracranial hemorrhage or in-hospital mortality across the anesthesia modalities in the extended window. Conclusion LA without sedation during EVT was associated with improved functional outcomes compared with GA, but not CS, within and beyond 6 hours from stroke onset. Prospective studies assessing anesthesia-related outcomes in the extended time window are warranted. [ABSTRACT FROM AUTHOR]

Background The effectiveness and safety of endovascular thrombectomy (EVT) in the late window (6--24 hours) for acute ischemic stroke (AIS) patients selected without advanced imaging is undetermined. We aimed to assess clinical outcomes and the relationship with time-to-EVT treatment beyond 6 hours of stroke onset without advanced neuroimaging. Methods Patients who underwent EVT selected with non-contrast CT/CT angiography (without CT perfusion or MR imaging), between October 2015 and March 2020, were included from a national stroke registry. Functional and safety outcomes were assessed in both early (<6 hours) and late windows with time analyzed as a continuous variable. Results Among 3278 patients, 2610 (79.6%) and 668 (20.4%) patients were included in the early and late windows, respectively. In the late window, for every hour delay, there was no significant association with shift towards poorer functional outcome (modified Rankin Scale (mRS)) at discharge (adjusted common OR 0.98, 95% CI 0.94 to 1.01, p=0.27) or change in predicted functional independence (mRS ≤2) (24.5% to 23.3% from 6 to 24 hours; aOR 0.99, 95% CI0.94 to 1.04, p=0.85). In contrast, predicted functional independence was time sensitive in the early window: 5.2% reduction per-hour delay (49.4% to 23.5% from 1 to 6 hours, p=0.0001). There were similar rates of symptomatic intracranial hemorrhage (sICH) (3.4% vs 4.6%, p=0.54) and in-hospital mortality (12.9% vs 14.6%, p=0.33) in the early and late windows, respectively, without a significant association with time. Conclusion In this real-world study, there was minimal change in functional disability, sICH and in-hospital mortality within and across the late window. While confirmatory randomized trials are needed, these findings suggest that EVT remains feasible and safe when performed in AIS patients selected without advanced neuroimaging between 6--24 hours from stroke onset. [ABSTRACT FROM AUTHOR]

Background The safety and functional outcome of endovascular thrombectomy (EVT) in the very late (VL; >24 hours) time window from ischemic stroke onset remains undetermined. Methods Using data from a national stroke registry, we used propensity score matched (PSM) individual level data of patients who underwent EVT, selected with CT perfusion or non-contrast CT/CT angiography, between October 2015 and March 2020. Functional and safety outcomes were assessed in both late (6-24 hours) and VL time windows. Subgroup analysis was performed of imaging selection modality in the VL time window. Results We included 1150 patients (late window: 1046 (208 after PSM); VL window: 104 (104 after PSM)). Compared with EVT treatment initiation between 6 and 24 hours, patients treated in the VL window had similar modified Rankin Scale (mRS) scores at discharge (ordinal shift; common 0R=1.08, 95% CI 0.69 to 1.47, p=0.70). No significant differences in achieving good functional outcome (mRS ≤2 at discharge; 28.8% (VL) vs 29.3% (late), 0R=0.97, 95% CI 0.58 to 1.64, p=0.93), successful reperfusion (modified Thrombolysis in Cerebral Infarction score of 2b-3) (p=0.77), or safety outcomes of symptomatic intracranial hemorrhage (p=0.43) and inhospital mortality (p=0.23) were demonstrated. In the VL window, there was no significant difference in functional outcome among patients selected with perfusion versus those selected without perfusion imaging (common 0R=1.38, 95% CI 0.81 to 1.76, p=0.18). Conclusion In this real world study, EVT beyond 24 hours from stroke onset or last known well appeared to be feasible, with comparable safety and functional outcomes to EVT initiation between 6 and 24 hours. Randomized trials assessing the efficacy of EVT in the VL window are warranted, but may only be feasible with a large international collaborative approach. [ABSTRACT FROM AUTHOR]