Publications by authors named "Raul Nogueira"

Introduction: The ANA™ (Anaconda Biomed) thrombectomy system is a novel stroke thrombectomy device comprising a self-expanding funnel designed to reduce clot fragmentation by locally restricting flow while becoming as wide as the lodging artery. Once deployed, ANA allows distal aspiration in combination with a stentretriever (SR) to mobilize the clot into the funnel where it remains copped during extraction. We investigate safety and efficacy of ANA™ in a first-in-man study.

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Background: There is a paucity of data regarding mechanical thrombectomy (MT) in distal arterial occlusions (DAO). We aim to evaluate the safety and efficacy of MT in patients with DAO and compare their outcomes with proximal arterial occlusion (PAO) strokes.

Methods: The Trevo Registry was a prospective open-label MT registry including 2008 patients from 76 sites across 12 countries.

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Article Synopsis
  • The COVID-19 pandemic has significantly impacted medical care, specifically leading to delays in acute stroke treatment at comprehensive stroke centers in the U.S.!* -
  • A study evaluating stroke patients admitted during the pandemic showed lower odds of receiving timely thrombolysis treatment within the Target: Stroke goal of 60 minutes compared to the pre-COVID-19 period, with a median delay of 4 minutes noted.!* -
  • The findings indicated that delays were primarily due to slower imaging to treatment times, although there were no significant delays in thrombectomy procedures during the same period.!*
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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 multiphase CT angiography (CTA) collateral status. This study compares baseline characteristics, workflow, and outcomes in the EVT arms of DAWN and DEFUSE-3 with late-window patients from the EVT-only arm of ESCAPE-NA1.

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Introduction: Carotid web is a radiographic entity located in the posterior aspect of the origin of the internal carotid arteries, considered to be a pathologic equivalent to intimal fibromuscular dysplasia, and has been implicated in acute ischemic strokes. The mechanism underlying its development is unknown and it remains unclear if this lesion is congenital or acquired. The aim of our study was to determine the frequency of carotid webs in a pediatric population with acute ischemic stroke (AIS).

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Background And Purpose: Speedy decision-making is important for optimal outcomes from endovascular thrombectomy (EVT) for acute ischemic stroke (AIS). Figural decision aids facilitate rapid review of treatment benefits and harms, but have not yet been developed for late-presenting patients selected for EVT based on multimodal computed tomography or magnetic resonance imaging.

Methods: For combined pooled study-level randomized trial (DAWN and DEFUSE 3) data, as well as each trial singly, 100 person-icon arrays (Kuiper-Marshall personographs) were generated showing beneficial and adverse effects of EVT for patients with AIS and large vessel occlusion using automated (algorithmic) and expert-guided joint outcome table specification.

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Cerebrovascular ischaemia is potentiated by hyperthermia, and even mild temperature elevation has proved detrimental to ischaemic brain. Infarction progression following endovascular reperfusion relates to multiple patient-specific and procedural variables; however, the potential influence of mild systemic temperature fluctuations is not fully understood. This study aims to assess the relationship between systemic temperatures in the early aftermath of acute ischaemic stroke and the loss of at-risk tissues, hypothesizing consumption of the ischaemic penumbra as a function of systemic temperatures, irrespective of reperfusion status.

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Purpose: There is little data and lack of consensus regarding antiplatelet management for intracranial stenting due to underlying intracranial atherosclerosis in the setting of endovascular treatment (EVT). In this DELPHI study, we aimed to assess whether consensus on antiplatelet management in this situation among experienced experts can be achieved, and what this consensus would be.

Methods: We used a modified DELPHI approach to address unanswered questions in antiplatelet management for intracranial stenting due to underlying atherosclerosis in the setting of EVT.

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Endovascular treatment is a highly effective therapy for acute ischemic stroke due to large vessel occlusion and has recently revolutionized stroke care. Oftentimes, ischemic core extent on baseline imaging is used to determine endovascular treatment-eligibility. There are, however, 3 fundamental issues with the core concept: First, computed tomography and magnetic resonance imaging, which are mostly used in the acute stroke setting, are not able to precisely determine whether and to what extent brain tissue is infarcted (core) or still viable, due to variability in tissue vulnerability, the phenomenon of selective neuronal loss and lack of a reliable gold standard.

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Background: Mechanical Thrombectomy (MT) is the standard of care for treatment of large vessel occlusion stroke. Until the beginning of 2020 MT was not funded nor widely implemented at the public healthcare level in Chile.

Objective: To describe the results of a pilot program created to provide access to public MT in Santiago - Chile.

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Background: Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has been associated with a significant risk of thrombotic events in critically ill patients.

Aim: To summarize the findings of a multinational observational cohort of patients with SARS-CoV-2 and cerebrovascular disease.

Methods: Retrospective observational cohort of consecutive adults evaluated in the emergency department and/or admitted with coronavirus disease 2019 (COVID-19) across 31 hospitals in four countries (1 February 2020-16 June 2020).

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Aneurysmal subarachnoid hemorrhage (SAH) patients require frequent neurological examinations, neuroradiographic diagnostic testing and lengthy intensive care unit stay. Previously established SAH treatment protocols are impractical to impossible to adhere to in the current COVID-19 crisis due to the need for infection containment and shortage of critical care resources, including personal protective equipment (PPE). Centers need to adopt modified protocols to optimize SAH care and outcomes during this crisis.

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Purpose: Previous work has shown that quantitative EEG measures correlate with the severity of ischemic stroke. This has not been systematically validated in patients with acute ischemic stroke who have undergone mechanical thrombectomy.

Methods: Data were collected from 73 patients who underwent mechanical thrombectomy and had a standard head set EEG performed during their hospital admission.

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Introduction: Although the 2019 severe acute respiratory syndrome coronavirus 2 infection (SARS-CoV-2, COVID-19) pandemic poses new challenges to the healthcare system to provide support for thousands of patients, there is special concern about common medical emergencies, such as stroke, that will continue to occur and will require adequate treatment. The allocation of both material and human resources to fight the pandemic cannot overshadow the care for acute stroke, a time-sensitive emergency that with an inefficient treatment will further increase mortality and long-term disability.

Objective: This paper summarizes the recommendations from the Scientific Department on Cerebrovascular Diseases of the Brazilian Academy of Neurology, the Brazilian Society of Cerebrovascular Diseases and the Brazilian Society of Neuroradiology for management of acute stroke and urgent neuro-interventional procedures during the COVID-19 pandemic, including proper use of screening tools, personal protective equipment (for patients and health professionals), and patient allocation.

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Background: The first-pass effect (FPE) has emerged as a key metric for efficacy in mechanical thrombectomy (MT). The hyperdense vessel sign (HDVS) on non-contrast head CT (NCCT) indicates a higher clot content of red blood cells.

Objective: To assess whether the HDVS could serve as an imaging biomarker for guiding first-line device selection in MT.

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The benefit of mechanical thrombectomy (MT) in acute ischemic stroke (AIS) due to large vessel intracranial occlusions is directly related to the technical success of the procedures in achieving fast and complete reperfusion. While a precise definition of refractoriness is lacking in the literature, it may be considered when there is reperfusion failure, long procedural times, or high number of passes with the MT devices. Detailed knowledge about the causes for refractory MT in AIS is limited; however, it is most likely a multifaceted problem including factors related to the vascular anatomy and the underlying nature of the occlusive lesion amongst other factors.

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Background: Larger bore aspiration catheters are expected to significantly improve the speed and completeness of acute stroke revascularization.

Objective: To evaluate the navigability and clot retrieval performance of a novel 8Fr aspiration catheter, Millipede 088 (Perfuze Ltd), using fresh-frozen cadavers and an in vitro thrombectomy model, respectively.

Methods: Transfemoral catheterization of the intracranial arteries was performed in six cadavers, allowing evaluation of navigation to 12 middle cerebral arteries (MCAs) and six basilar arteries.

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Background: This survey was focused on the provision of neurointerventional services, the current practices of managing patients under COVID-19 conditions, and the expectations for the future.

Methods: Invitations for this survey were sent out as a collaborative effort of the European Society of Minimally Invasive Neurological Therapy (ESMINT), the Society of NeuroInterventional Surgery (SNIS), the Sociedad Iberolatinoamericana de Neuroradiologia Diagnostica y Terapeutica (SILAN), the Society of Vascular and Interventional Neurology (SVIN), and the World Federation of Interventional and Therapeutic Neuroradiology (WFITN).

Results: Overall, 475 participants from 61 countries responded (six from Africa (1%), 81 from Asia (17%), 156 from Europe (33%), 53 from Latin America (11%), and 172 from North America (11%)).

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Background: Randomized trials involving patients with stroke have established that outcomes are improved with the use of thrombectomy for large-vessel occlusion. These trials were performed in high-resource countries and have had limited effects on medical practice in low- and middle-income countries.

Methods: We studied the safety and efficacy of thrombectomy in the public health system of Brazil.

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Objective: To examine outcomes for thrombectomy devices used for treatment of acute ischemic stroke (AIS) with middle cerebral artery (MCA) M2 segment emergent large vessel occlusion (ELVO) as the optimal device for such reperfusion is not clearly defined.

Methods: A retrospective cohort study of consecutive AIS patients with MCA M2 ELVO undergoing thrombectomy from 3 academic medical centers was conducted from October 1999 through June 2016. The patients were divided based on the device utilized.

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Background And Purpose: Several reports have described lower mortality rates in overweight or obese patients as compared to normal weight ones. In the past decade, several studies have investigated the phenomenon, commonly known as the obesity paradox, with mixed results thus far. We sought to determine whether outcomes differ between patients with large vessel occlusion strokes (LVOS) after endovascular therapy (ET) according to their body mass index (BMI).

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Background: We aim to evaluate the speed and rates of reperfusion in tandem large vessel occlusion acute stroke patients undergoing upfront cervical lesion treatment (Neck-First: angioplasty and/or stent before thrombectomy) as compared to direct intracranial occlusion therapy (Head-First) in a large international multicenter cohort.

Methods: The Thrombectomy In TANdem Lesions (TITAN) collaboration pooled individual data of prospectively collected thrombectomy international databases for all consecutive anterior circulation tandem patients who underwent emergent thrombectomy. The co-primary outcome measures were rates of successful reperfusion (modified Thrombolysis in Cerebral Infarction 2b/3) and time from groin puncture to successful reperfusion.

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Background: Eight randomized controlled trials have consistently shown that endovascular treatment plus best medical treatment improves outcome after acute anterior proximal intracranial large vessel occlusion strokes. Whether intravenous thrombolysis prior to endovascular treatment in patients with anterior circulation, large vessel occlusion is of any additional benefits remains unclear.

Objective: This study compares the safety and efficacy of direct endovascular treatment versus intravenous recombinant tissue-type plasminogen activator bridging with endovascular treatment (bridging therapy) in acute stroke patients with intracranial internal carotid artery or middle cerebral artery-M1 occlusion within 4.

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