Alexandre Y Poppe

Université de Montréal | UdeM · Department of Neurosciences

BACKGROUND The AcT (Alteplase Compared to Tenecteplase) randomized controlled trial showed that tenecteplase is noninferior to alteplase in treating patients with acute ischemic stroke within 4.5 hours of symptom onset. The effect of time to treatment on clinical outcomes with alteplase is well known; however, the nature of this relationship is yet...

Objective There is limited evidence on when to obtain a central nervous system (CNS) biopsy in suspected primary angiitis of the central nervous system (PACNS). Our objective was to identify which clinical and radiological characteristics were associated with a positive biopsy in PACNS. Methods From the multicenter retrospective Cohort of Patients...

Background Carotid tandem lesions ((TL) ⩾70% stenosis or occlusion) account for 15–20% of acute stroke with large vessel occlusion. Aims We investigated the safety and efficacy of intravenous tenecteplase (0.25 mg/kg) versus intravenous alteplase (0.9 mg/kg) in patients with carotid TL. Methods This is a substudy of the alteplase compared with th...

Advance consent could allow individuals at high risk of stroke to provide consent before they might become eligible for enrollment in acute stroke trials. This survey explores the acceptability of this novel technique to Canadian Research Ethics Board (REB) chairs that review acute stroke trials. Responses from 15 REB chairs showed that majority of...

Background: Sex differences in treatment response to intravenous thrombolysis (IVT) are poorly characterized. We compared sex-disaggregated outcomes in patients receiving IVT for acute ischemic stroke in the Alteplase compared to Tenecteplase (AcT) trial, a Canadian multicentre, randomised trial. Methods: In this post-hoc analysis, the primary outc...

Background: The Alteplase compared to Tenecteplase (AcT) randomized controlled trial (RCT) showed that tenecteplase is non-inferior to alteplase in treating acute ischemic stroke within 4.5 hours of symptom onset. The effect of time to treatment on clinical outcomes with alteplase is well known, however the nature of this relationship is yet to be...

Background: Infarct in a new territory (INT) is a known complication of endovascular stroke therapy. We assessed the incidence of INT, outcomes after INT, and the impact of concurrent treatments with intravenous thrombolysis and nerinetide. Methods: Data are from ESCAPE-NA1 trial (Safety and Efficacy of Nerinetide [NA-1] in Subjects Undergoing E...

Background and aims: Face, arm, speech, time (FAST) public awareness campaigns improve stroke recognition in the general population. Whether this translates into improved emergency medical services (EMS) activation remains unclear. We assessed the association of five consecutive FAST campaigns with EMS calls for suspected strokes in a large urban...

Advance consent presents a potential solution to the challenge of obtaining informed consent for participation in acute stroke trials. Clinicians in stroke prevention clinics are uniquely positioned to identify and seek consent from potential stroke trial participants. To assess the acceptability of advance consent to Canadian stroke clinic physici...

Background: Arterial perforation is a potentially serious complication during endovascular thrombectomy. Purpose: Our aim was to describe interventional approaches after arterial perforation during endovascular thrombectomy and to determine whether reperfusion remains associated with favorable outcome despite this complication. Data sources: D...

Background First‐pass effect (FPE), that is, achieving reperfusion with a single thrombectomy device pass, is associated with better clinical outcomes in patients with acute stroke. FPE is therefore increasingly used as a marker of device and procedural efficacy. We aimed to evaluate the ability of thrombus‐based radiomics models to predict FPE in...

Background: Intravenous thrombolysis with alteplase bolus followed by infusion is a global standard of care for patients with acute ischaemic stroke. We aimed to determine whether tenecteplase given as a single bolus might increase reperfusion compared with this standard of care. Methods: In this multicentre, open-label, parallel-group, registry...

Background Although the association between cortical venous opacification (VO) and clinical outcomes has been shown in previous studies, little is known about the relationship between parenchymal hemorrhage (PH) and VO in patients with acute stroke. We aimed to determine whether cortical VO assessed on computed tomography angiography correlates wit...

Background: Face, Arm, Speech, Time (FAST) campaigns improve stroke recognition in the general population. We assessed the effect of five consecutive FAST campaigns on emergency medical services (EMS) calls for suspected strokes in Quebec, Canada. Methods: We compared with t-tests the daily EMS call volume changes in the greater Montreal area befor...

Objectives: We evaluated whether clinicians agree in the detection of non-contrast CT markers of intracerebral hemorrhage (ICH) expansion. Methods: From our local dataset, we randomly sampled 60 patients diagnosed with spontaneous ICH. Fifteen physicians and trainees (Stroke Neurology, Interventional and Diagnostic Neuroradiology) were trained t...

Background Patients with pre-stroke disability, defined as a modified Rankin Scale (mRS) ≥3, were excluded from most trials of endovascular thrombectomy (EVT) for acute stroke. We sought to evaluate the prognostic factors associated with favorable outcome in stroke patients with known disability undergoing EVT, and the impact of successful reperfus...

Introduction: First-pass effect (FPE), i.e., achieving reperfusion with a single thrombectomy device pass, is associated with better clinical outcomes in patients with acute stroke. FPE is therefore increasingly being used as a marker of device and procedural efficacy. We evaluated the ability of thrombus-based radiomics models to predict FPE in pa...

Background Successful reperfusion determines the treatment effect of endovascular thrombectomy. We evaluated stent-retriever characteristics and their relation to reperfusion in the ESCAPE-NA1 trial. Methods Independent re-scoring of reperfusion grade for each attempt was conducted. The following characteristics were evaluated: stent-retriever len...

Importance Some patients have poor outcomes despite small infarcts after endovascular therapy (EVT), while others with large infarcts do well. Understanding why these discrepancies occur may help to optimize EVT outcomes. Objective To validate exploratory findings from the Endovascular Treatment for Small Core and Anterior Circulation Proximal Occ...

Background The DAWN and DEFUSE-3 trials showed the benefit of endovascular treatment (EVT) in acute ischemic stroke patients presenting beyond 6 hours from last known well (LKW) and selected by perfusion imaging criteria. The ESCAPE NA1-trial selected patients based on non-contrast CT (NCCT) Alberta Stroke Program Early CT Score (ASPECTS) and multi...

Background and purposeEndovascular treatment (EVT) is a powerful treatment for large vessel occlusion (LVO) stroke if reperfusion can be achieved, while in cases with failed reperfusion, EVT may cause harm, as procedure-related complications may occur. We hypothesized that EVT with failed recanalization does not result in worse outcomes compared to...

Background: Some patients do poorly despite small infarcts after endovascular therapy(EVT) whilst others with large infarcts do well. We validated exploratory findings from the ESCAPE trial regarding factors associated with such discrepancies, in the ESCAPE-NA1 trial(NCT02930018). Methods: We identified “discrepant cases” with modified Rankin Scale...

Background: We evaluated (1) the predictive accuracy and (2) multi-observer reliability of non-contrast CT markers of hematoma expansion (HE). Methods: In 124 patients with spontaneous intracerebral hemorrhage, two investigators documented the presence of six density (Barras density, hypodensity, black hole, swirl, blend, fluid level) and three sha...

Background: Predicting outcomes after endovascular treatment (EVT) for acute ischemic stroke with baseline variables remains a challenge. We assessed the performance of stroke outcome prediction models for EVT in acute ischemic stroke in an iterative fashion using baseline, treatment-related and post-treatment variables. Methods: Data from the ESCA...

Background Determining infarct progression rate in acute ischemic stroke (AIS) is important for patient triage, treatment decision-making, and outcome prognostication. Objective To estimate infarct progression rate in patients with AIS with large vessel occlusion (LVO) and determine its predictors and impact on clinical outcome. Methods Data are...

PurposeThere are few data on the prevalence and impact of isolated deep grey matter infarction in acute stroke. In this study, we aimed to investigate the prevalence of isolated deep grey matter infarcts and their impact on the outcome.Methods Infarcts on 24-h follow-up imaging (non-contrast head CT or diffusion-weighted MRI) in the ESCAPE-NA1 tria...

Background and purpose: Infarct volume is an important predictor of clinical outcome in acute stroke. We hypothesized that the association of infarct volume and clinical outcome changes with the magnitude of infarct size. Materials and methods: Data were derived from the Safety and Efficacy of Nerinetide in Subjects Undergoing Endovascular Throm...

The 2020 update of the Canadian Stroke Best Practice Recommendations (CSBPR) for the Secondary Prevention of Stroke includes current evidence-based recommendations and expert opinions intended for use by clinicians across a broad range of settings. They provide guidance for the prevention of ischemic stroke recurrence through the identification and...

Background The COVID-19 pandemic has disrupted acute stroke care logistics, including delays in hyperacute management and decreased monitoring following endovascular therapy (EVT). We aimed to assess the impact of the pandemic on 90-day functional outcome among patients treated with EVT. Methods This is an observational cohort study including all...

Background Intracranial hemorrhage is a known complication after endovascular treatment in patients with acute ischemic stroke due to large vessel occlusion, but the association between radiologic hemorrhage severity and outcome is controversial. Purpose To investigate the prevalence and impact on outcome of intracranial hemorrhage and hemorrhage s...

Background The effect of infarct pattern on functional outcome in acute ischemic stroke is incompletely understood. Purpose To investigate the association of qualitative and quantitative infarct variables at 24-hour follow-up noncontrast CT and diffusion-weighted MRI with 90-day clinical outcome. Materials and Methods The Safety and Efficacy of Ner...

Background: The optimal treatment and prognosis for stroke patients with tandem cervical carotid occlusion are unclear. We analyzed outcomes and treatment strategies of tandem occlusion patients in the ESCAPE-NA1 trial. Methods: ESCAPE-NA1 was a multicenter international randomized trial of nerinetide versus placebo in 1105 patients with acute i...

Importance The benefits of endovascular thrombectomy (EVT) are time dependent. Prior studies may have underestimated the time-benefit association because time of onset is imprecisely known. Objective To assess the lifetime outcomes associated with speed of endovascular thrombectomy in patients with acute ischemic stroke due to large-vessel occlusi...

Background Prehospital delays are a major obstacle to timely reperfusion therapy in acute ischemic stroke. Stroke sign recognition, however, remains poor in the community. We present an analysis of repeated surveys to assess the impact of Face, Arm, Speech, Time (FAST) public awareness campaigns on stroke knowledge. Methods Four cross-sectional su...

Introduction: Several comprehensive stroke centers (CSC) have reported increased delays to reperfusion in acute stroke during the COVID-19 pandemic, but it is unknown whether the pandemic is associated with worse functional outcomes in EVT-treated patients. Methods: We performed an observational cohort study of consecutive adult patients evaluated...

Background and Purpose Endovascular thrombectomy (EVT) reduces 90-day disability in patients following acute ischemic stroke due to large vessel occlusion. Patient-reported outcome measures after EVT, such as health-related quality of life and specific functional domains, are less well described. Methods We report outcomes on the EuroQol-5D (EQ-5D...

Background The effectiveness of mechanical thrombectomy (MT) in elderly stroke patients remains debated. We aimed to describe outcomes and their predictors in a cohort of patients aged ≥ 85 years treated with MT. Methods Data from consecutive patients aged ≥ 85 years undergoing MT at two stroke centers between January 2016 and November 2019 were r...

Background and purposes: Stroke severity scales may expedite prehospital large vessel occlusion (LVO) stroke detection, but few are validated for paramedic use. We evaluated the feasibility of introducing the Cincinnati Stroke Triage Assessment Tool (C-STAT) in the field and its capacity to detect LVO stroke. Methods: We performed a prospective par...

Introduction: Emboli in new territory (ENT) are known potential complication of endovascular thrombectomy. We explored their incidence and predictors in ESCAPE-NA-1 trial. Methods: We included patients from the ESCAPE-NA1: a multicenter, international randomized study that assessed the efficacy of intravenous nerinetide in patients with acute ische...

Background: The optimal treatment for stroke patients with tandem cervical carotid occlusion is debated. We analyzed the treatment strategies and outcomes of tandem occlusion patients in the ESCAPE NA1 trial. Methods: ESCAPE NA1 was a multicenter international randomized trial of nerinetide vs. placebo in patients with acute ischemic stroke who und...

Background: We evaluated clinical outcome in relation to the degree of reperfusion in ESCAPE-NA1 trial. Methods: ESCAPE-NA1 was a multicenter, international randomized trial assessing the efficacy of nerinetide in ischemic stroke patients who underwent EVT within 12h from onset. Independent clinical outcome [90-days modified Rankin Scale (mRS) 0-2]...

Purpose: In this post-hoc analysis of the ESCAPE-NA1 trial, we investigated the prevalence of deep grey matter infarcts and their influence on clinical outcome. Methods: Infarcts on 24 hour follow up imaging (non contrast head CT or diffusion-weighted MRI) were categorized as predominantly deep grey matter infarcts (caudate and/or lentiform nucleus...

Introduction: Infarct in new territory (INT) is a known complication of endovascular therapy. We assessed the prevalence, predictors and clinical relevance of INT Methods: We included patients from the ESCAPE-NA1: a multicenter, international randomized study that assessed the efficacy of intravenous nerinetide in patients with acute ischemic strok...

Background: We evaluated technical aspects of stent retriever use and its relation to reperfusion in ESCAPE NA1 trial. Methods: ESCAPE-NA1 was a multicenter, international randomized trial assessing the efficacy of nerinetide in ischemic stroke patients who underwent EVT within 12h from onset. The following stent retriever characteristics were eval...

Purpose: We assessed whether balloon guide catheter (BGC) use during endovascular thrombectomy (EVT) influences procedural and clinical outcomes in the ESCAPE-NA1 trial. Methods: ESCAPE-NA1 was an international multicenter trial that randomized large vessel occlusion stroke patients who underwent endovascular thrombectomy (EVT) to receive Nerinetid...

Background: Endovascular thrombectomy (EVT) improves 90-day disability in patients following acute ischemic stroke due to large vessel occlusion. However, the effect of EVT on health-related quality of life and specific functional domains, and whether this effect differs by age or sex is less studied. Methods: We used data from the ESCAPE randomize...

Background: The degree of cortical venous opacification could reflect the degree of ischemia in tandem occlusions strokes. We assessed the association between asymmetric cortical vein opacification and outcome among patients with acute ischemic stroke and tandem occlusion. Methods: ESCAPE NA1 was a multicenter randomized-controlled trial comparing...

Background: Time from imaging to establishing reperfusion is a major influencer of clinical outcomes and over the years thrombectomy techniques have evolved rapidly. This has led to improvements in achieving fast and complete reperfusion. We analyzed the impact of various intra-procedural techniques and tools on the speed of reperfusion and correla...

Purpose: We investigated the prevalence and prognostic impact on outcome of any intracranial hemorrhage, hemorrhage morphology, type and volume in acute ischemic stroke patients undergoing mechanical thrombectomy. Methods: Prevalence of intracranial hemorrhage, hemorrhage type, morphology and volume was determined on 24h follow-up imaging (non cont...

Background During the Randomized Assessment of Rapid Endovascular Treatment (EVT) of Ischemic Stroke (ESCAPE) trial, patient-level micro-costing data were collected. We report a cost-effectiveness analysis of EVT, using ESCAPE trial data and Markov simulation, from a universal, single-payer system using a societal perspective over a patient’s lifet...

Background and purpose: There is interest in what happens over time to the thrombus after intravenous alteplase. We study the effect of alteplase on thrombus structure and its impact on clinical outcome in patients with acute stroke. Methods: Intravenous alteplase treated stroke patients with intracranial internal carotid artery or middle cerebral...

Background and Purpose Quantitating the effect of intravenous alteplase on the technical outcome of early recanalization of large vessel occlusions aids understanding. We report the prevalence of early recanalization in patients with stroke because of large vessel occlusion treated with and without intravenous alteplase and endovascular thrombectom...

Background and Purpose Available data on the clinical course of patients with acute ischemic stroke due to medium vessel occlusion (MeVO) are mostly limited to those with M2 segment occlusions. Outcomes are generally better compared with more proximal occlusions, but many patients will still suffer from severe morbidity. We aimed to determine the c...

This is an observational cohort study comparing 156 patients evaluated for acute stroke between March 30th and May 31st 2020 at a comprehensive stroke center with 138 patients evaluated during the corresponding time period in 2019. During the pandemic, the proportion of COVID- 19 positive patients was low (3%), the time from symptom-onset to hospit...

Background The benefit of acute carotid stenting compared with no acute stenting on clinical outcomes among patients with tandem lesions (TL) undergoing endovascular thrombectomy (EVT) remains unknown. Methods We conducted a a systematic review and meta-analysis of studies comparing acute carotid stenting versus no stenting among TL patients under...

Background Some patients with ischemic stroke have poor outcomes despite small infarcts after endovascular thrombectomy, while others with large infarcts sometimes fare better. Aims We explored factors associated with such discrepancies between post-treatment infarct volume (PIV) and functional outcome. Methods We identified patients with small P...

Approximately 15% of patients undergoing endovascular thrombectomy for anterior circulation acute ischemic stroke have a tandem lesion, defined as a severe stenosis or occlusion of the cervical internal carotid artery ipsilateral to its intracranial occlusion. Patients with tandem lesions have worse outcomes than patients with isolated intracranial...

Background Anecdotal cases of exophthalmos after acute mechanical thrombectomy have been described. We sought to estimate the incidence in a large cohort of patients with acute anterior circulation stroke treated with mechanical thrombectomy. Secondarily, we aimed to evaluate the underlying mechanism and to differentiate it on imaging from other pa...

Hypertension Canada’s 2020 guidelines for the prevention, diagnosis, risk assessment, and treatment of hypertension in adults and children provide comprehensive, evidence-based guidance for health care professionals and patients. Hypertension Canada develops the guidelines using rigourous methodology, carefully mitigating the risk of bias in our pr...

Background and purpose: Standard poststroke treatment monitoring protocols are made problematic during the coronavirus disease 2019 (COVID-19) pandemic by the frequency of patient assessments, requiring repeated donning and doffing procedures in a short interval of time. Methods: A streamlined poststroke treatment protocol was developed to limit...

Chronic Atrial Intestinal Dysrhythmia Syndrome Is Associated with Cerebral Small Vessel Disease and Predominantly Cerebellar Microbleeds - Ahmad Nehme, Laura C. Gioia, Grégory Jacquin, Alexandre Y. Poppe, Laurent Létourneau-Guillon, Céline Odier

Background Nerinetide, an eicosapeptide that interferes with post-synaptic density protein 95, is a neuroprotectant that is effective in preclinical stroke models of ischaemia-reperfusion. In this trial, we assessed the efficacy and safety of nerinetide in human ischaemia-reperfusion that occurs with rapid endovascular thrombectomy in patients who...

Purpose To compare the association of different measures of intracranial thrombus permeability on non-contrast computerized tomography (NCCT) and computed tomography angiography (CTA) with recanalization with or without intravenous alteplase. Methods Patients with anterior circulation occlusion from the INTERRSeCT study were included. Thrombus per...

Background: Nerinetide, an eicosapeptide that interferes with post-synaptic density protein 95, is a neuroprotectant that is effective in preclinical stroke models of ischaemia-reperfusion. In this trial, we assessed the efficacy and safety of nerinetide in human ischaemia-reperfusion that occurs with rapid endovascular thrombectomy in patients wh...

Introduction: The benefit of late window endovascular treatment (EVT) for anterior circulation ischemic stroke has been demonstrated using perfusion-based neuroimaging. We evaluated whether non-contrast CT (NCCT) and CT-angiogram (CTA) alone can select late-presenting patients for EVT. Methods: We performed a retrospective comparison of all pati...

Background: The Alberta Stroke Program Early CT Score (ASPECTS) is a systematic method of assessing extent of early ischemic change on Non-Contrast CT (NCCT) in patients with acute ischemic stroke (AIS). Our objective was to validate an automated ASPECTS scoring method we recently developed on a large dataset. Materials and Methods: We retrospecti...

Background and purpose: The optimal management of patients with tandem lesions (TL), or cervical internal carotid artery (c-ICA) steno-occlusive pathology and ipsilateral intracranial occlusion, who are undergoing endovascular thrombectomy (EVT) remains unknown. We sought to establish the feasibility of a trial designed to address this question....

Introduction: Prehospital identification of large vessel occlusion (LVO) stroke may expedite treatment by direct transport to comprehensive stroke centers (CSCs) with endovascular capabilities. The Cincinnati Prehospital Stroke Scale (CPSS) is commonly used for prehospital stroke detection. We aimed to assess whether (1) a high CPSS score can iden...

Together, transient ischemic attack (TIA) and minor stroke represent the largest group of cerebrovascular events, with one study estimating that over 80% of all stroke patients fall into this category [1]. With the advent of reperfusion therapies for acute ischemic stroke, systems of care have been streamlined such that patients with disabling or n...

Background and Purpose— In patients with acute stroke caused by tandem occlusion, the benefit of immediate revascularization (stenting) of the cervical internal carotid artery lesion during endovascular thrombectomy is uncertain. We sought to determine current practice patterns and whether consensus existed among physicians with stroke expertise....

Contexte et objectifs Des cas anecdotiques d’exophtalmie après thrombectomie mécanique aiguë (MT) ont été décrits. Avec cette étude, nous avons cherché à estimer l’incidence dans une large cohorte de patients ayant subi un AVC aigu de la circulation antérieure traité par MT. Deuxièmement, nous avons cherché à évaluer le mécanisme sous-jacent à ce p...

Introduction: There is interest in understanding thrombus dynamics from IV TPA prior to endovascular thrombectomy (EVT) given the possible dichotomy amongst sites of occlusion for IV TPA benefit/harm. Kaesmacher et al reported beneficial 5+% rates of early TICI > 2a reperfusion in distal M1 or M2 MCA occlusions with IV TPA. However in more proximal...