Hypoperfusion index ratio and pretreatment with intravenous thrombolysis are independent predictors of good functional outcome in acute ischemic stroke patients with large vessel occlusion treated with acute reperfusion therapies.

INTRODUCTION: We aimed to investigate the performance of several neuroimaging markers provided by perfusion imaging of Acute Ischemic Stroke (AIS) patients with large vessel occlusion (LVO) in order to predict clinical outcomes following reperfusion treatments. METHODS: We prospectively evaluated consecutive AIS patients with LVO who were treated with reperfusion therapies, during a six-year period. In order to compare patients with good (mRS scores 0-2) and poor (mRS scores 3-6) functional outcomes, data regarding clinical characteristics, the Alberta Stroke Programme Early Computed Tomography Score (ASPECTS) based on unenhanced computed tomography (CT), CT angiography collateral status and perfusion parameters including ischemic core, hypoperfusion volume, mismatch volume between core and penumbra, Tmax > 10 s volume, CBV index and the Hypoperfusion Index Ratio (HIR) were assessed. RESULTS: A total of 84 acute stroke patients with LVO who met all the inclusion criteria were enrolled. In multivariable logistic regression models increasing age (odds ratio [OR]: 0.93; 95%CI: 0.88-0.96, p = 0.001), lower admission National Institute of Health Stroke Scale (NIHSS)-score (OR: 0.88; 95%CI: 0.80-0.95, p = 0.004), pretreatment with intravenous thrombolysis (OR: 3.83; 95%CI: 1.29-12.49, p = 0.019) and HIR (OR:0.36; 95%CI: 0.10-0.95, p = 0.042) were independent predictors of good functional outcome at 3 months. The initial univariable associations between HIR and higher likelihood for symptomatic intracranial hemorrhage (sICH) and parenchymal hematoma type 2 (PH2) were attenuated in multivariable analyses failing to reach statistical significance. DISCUSSION: Our pilot observational study of unselected AIS patients with LVO treated with reperfusion therapies demonstrated that pre-treatment low HIR in perfusion imaging and IVT were associated with better functional outcomes.

Overview of systematic reviews comparing endovascular to best medical treatment for large-vessel occlusion acute ischaemic stroke: an umbrella review.

Background: The literature on endovascular treatment (EVT) for large-vessel occlusion (LVO) acute ischaemic stroke (AIS) has been rapidly increasing after the publication of positive randomized-controlled clinical trials (RCTs) and a plethora of systematic reviews (SRs) showing benefit compared to best medical therapy (BMT) for LVO. Objectives: An overview of SRs (umbrella review) and meta-analysis of primary RCTs were performed to summarize the literature and present efficacy and safety of EVT. Design and methods: MEDLINE via Pubmed, Embase and Epistemonikos databases were searched from January 2015 until 15 October 2023. All SRs of RCTs comparing EVT to BMT were included. Quality was assessed using Risk of Bias in Systematic Reviews scores and the RoB 2 Cochrane Collaboration tool, as appropriate. GRADE approach was used to evaluate the strength of evidence. Data were presented according to the Preferred Reporting Items for Overviews of Reviews statement. The primary outcome was 3-month good functional outcome [modified Rankin scale (mRS) score 0-2]. Results: Three eligible SRs and 4 additional RCTs were included in the overview, comprising a total of 24 RCTs, corresponding to 5968 AIS patients with LVO (3044 randomized to EVT versus 2924 patients randomized to BMT). High-quality evidence shows that EVT is associated with an increased likelihood of good functional outcome [risk ratio (RR) 1.78 (95% confidence interval (CI): 1.54-2.06); 166 more per 1000 patients], independent ambulation [mRS-scores 0-3; RR 1.50 (95% CI: 1.37-1.64); 174 more per 1000 patients], excellent functional outcome [mRS-scores 0-1; RR 1.90 (95% CI: 1.62-2.22); 118 more per 1000 patients] at 3 months. EVT was associated with reduced 3-month mortality [RR 0.81 (95% CI: 0.74-0.88); 61 less per 1000 patients] despite an increase in symptomatic intracranial haemorrhage [sICH; RR 1.65 (95% CI: 1.23-2.21); 22 more per 1000 patients]. Conclusion: In patients with AIS due to LVO in the anterior or posterior circulation, within 24 h from symptom onset, EVT improves functional outcomes and increases the chance of survival despite increased sICH risk. Registration: PROSPERO Registration Number CRD42023461138.

Carotid-cavernous fistula: A potential treatable cause of bilateral abducens palsy and conjunctival hyperemia.

OBJECTIVE: Carotid cavernous fistulas (CCFs) represent uncommon and anomalous communications between the carotid artery and the cavernous sinus. MATERIALS AND METHODS: Case report RESULTS: We present the clinical details and successful management of a previously healthy 44-year-old patient who presented with one-month worsening headache, bilateral abducens palsy and conjunctival injection. Imaging modalities including magnetic resonance imaging (MRI) with contrast and digital subtraction angiography (DSA) facilitated the diagnosis of CCF. The patient underwent endovascular coiling of the CCF, leading to neurological recovery and symptom remission. CONCLUSION: This case highlights the importance of promptly CCF diagnosis in patients with multiple cranial nerve palsies and conjunctival hyperemia. Moreover, it emphasizes the efficacy of endovascular coiling in achieving symptom remission.

Endovascular treatment for large-core ischaemic stroke: a meta-analysis of randomised controlled clinical trials.

BACKGROUND AND PURPOSE: Current guidelines recommend endovascular treatment (EVT) for acute ischaemic stroke (AIS), due to large-vessel occlusion and an Alberta Stroke Program Early CT Score (ASPECTS) of ≥6. High-quality evidence resulting from randomised controlled clinical trials (RCTs) regarding EVT among large-core AIS has recently become available, justifying an updated meta-analysis aiming to evaluate efficacy and safety of EVT in this clinical setting. METHODS: We conducted a systematic review and meta-analysis including all available RCTs that compared EVT in addition to best medical treatment (BMT) versus BMT alone for large-core AIS (defined by ASPECTS 2-5 or volumetric methods). The primary outcome was reduced disability at 3 months (≥1-point reduction across all Modified Rankin Scale (mRS) grades). Secondary outcomes included independent ambulation at 3 months (mRS score 0-3), good functional outcome at 3 months (mRS score 0-2), excellent functional outcome at 3 months (mRS score 0-1), symptomatic intracranial haemorrhage (sICH) and any intracranial haemorrhage (ICH) and mortality at 3 months. The random-effects model was used. RESULTS: Four RCTs were included comprising a total of 662 patients treated with EVT vs 649 patients treated with BMT. Compared with BMT, EVT was significantly associated with reduced disability (common OR 1.70, 95% CI 1.39 to 2.07; I2=0%), independent ambulation (risk ratio (RR) 1.69, 95% CI 1.33 to 2.14; I2=39%) and good functional outcome (RR 2.33, 95% CI 1.76 to 3.10; I2=0%), but not with excellent functional outcome (RR 1.46, 95% CI 0.91 to 2.33; I2=39%) at 3 months. Although rates of sICH (RR 1.98, 95% CI 1.07 to 3.68; I2=0%) and any ICH (RR 2.13, 95% CI 1.70 to 2.66; I2=37%) were higher in the EVT group, 3-month mortality (RR 0.98, 95% CI 0.83 to 1.15; I2=0%) did not differ between the two groups. CONCLUSION: EVT appears to be effective and safe and may be considered for the treatment of large-core AIS, as assessed by ASPECTS of 2-5 or volumetric methods. PROSPERO REGISTRATION NUMBER: CRD42022334417.

Endovascular Treatment for Acute Basilar Artery Occlusion: A Fragility Index Meta-Analysis.

INTRODUCTION: High-quality evidence regarding the use of endovascular treatment (EVT) in patients with acute basilar artery occlusion (BAO) has been provided by recently completed randomized controlled clinical trials (RCTs). METHODS: We conducted a systematic review and meta-analysis including all available RCTs that investigated efficacy and safety of EVT in addition to best medical treatment (BMT) versus BMT alone for BAO. The random-effects model was used, while the fragility index (FI) was calculated for dichotomous outcomes of interest. RESULTS: Four RCTs were included comprising a total of 988 patients with acute BAO (mean age: 65.6 years, 70% men, median NIHSS: 24, 39% pretreatment with intravenous thrombolysis). EVT was related to higher likelihood of good functional outcome (RR: 1.54; 95% CI: 1.16-2.05; I2 = 60%), functional independence (RR: 1.83; 95% CI: 1.08-3.08; I2 = 79%) and reduced disability at 3 months (adjusted common OR: 1.96; 95% CI: 1.26-3.05; I2 = 59%) compared to BMT alone. Despite that EVT was associated with a higher risk for symptomatic intracranial hemorrhage (RR: 7.78; 95% CI: 2.36-25.61; I2 = 0%) and any intracranial hemorrhage (RR: 2.85; 95% CI: 1.50-5.44; I2 = 16%), mortality at 3 months was lower among patients that received EVT plus BMT versus BMT alone (RR: 0.76; 95% CI: 0.65-0.89; I2 = 0%). However, sufficient robustness was not evident in any of the reported associations (FI < 10) including the overall effect regarding the primary outcome. The former associations were predominantly driven by RCTs with recruitment limited in China. CONCLUSIONS: EVT combined with BMT is associated with a higher likelihood of achieving good functional outcomes and a lower risk of death at 3 months compared to BMT alone, despite the higher risk of sICH. An individual-patient data meta-analysis is warranted to uncover and adjust for potential sources of heterogeneity and to provide further insight.

Quality metrics in the management of acute stroke in Greece during the first 5 years of Registry of Stroke Care Quality (RES-Q) implementation.

Introduction: Establishment of a prospective stroke registry may promote the documentation and improvement of acute stroke care. We present the status of stroke management in Greece using the Registry of Stroke Care Quality (RES-Q) dataset. Methods: Consecutive patients with acute stroke were prospectively registered in RES-Q registry by contributing sites in Greece during the years 2017-2021. Demographic and baseline characteristics, acute management, and clinical outcomes at discharge were recorded. Stroke quality metrics, with a specific interest in the association between acute reperfusion therapies and functional recovery in ischemic stroke patients are presented. Results: A total of 3590 acute stroke patients were treated in 20 Greek sites (61% men, median age 64 years; median baseline NIHSS 4; 74% ischemic stroke). Acute reperfusion therapies were administered in almost 20% of acute ischemic stroke patients, with a door to needle and door to groin puncture times of 40 and 64 min, respectively. After adjustment for contributing sites, the rates of acute reperfusion therapies were higher during the time epoch 2020-2021 compared to 2017-2019 (adjusted OR 1.31; 95% CI 1.04-1.64; p < 0.022; Cochran-Mantel-Haenszel test). After propensity-score-matching, acute reperfusion therapies administration was independently associated with higher odds of reduced disability (one point reduction across all mRS scores) at hospital discharge (common OR 1.93; 95% CI 1.45-2.58; p < 0.001). Conclusions: Implementation and maintenance of a nationwide stroke registry in Greece may guide the stroke management planning, so that prompt patient transportation, acute reperfusion therapies, and stroke unit hospitalization become more widely accessible, improving the functional outcomes of stroke patients.

Diagnosis and treatment of acute isolated proximal internal carotid artery occlusions: a narrative review.

The clinical manifestations of proximal (extracranial) internal carotid artery occlusions (pICAOs) may range from asymptomatic to acute, large, and devastating ischemic strokes. The etiology and pathophysiology of the occlusion, intracranial collateral status and patient's premorbid status are among the factors determining the clinical presentation and outcome of pICAOs. Rapid and accurate diagnosis is crucial and may be assisted by the combination of carotid and transcranial duplex sonography, or a computed tomography/magnetic resonance angiography (CTA/MRA). It should be noted that with either imaging modalities, the discrimination of a pseudo-occlusion of the extracranial internal carotid artery (ICA) from a true pICAO may not be straightforward. In the absence of randomized data, the management of acute, symptomatic pICAOs remains individualized and relies largely on expert opinion. Administration of intravenous thrombolysis is reasonable and probably beneficial in the settings of acute ischemic stroke with early presentation. Unfortunately, rates of recanalization are rather low and acute interventional reperfusion therapies emerge as a potentially powerful therapeutic option for patients with persistent and severe symptoms. However, none of the pivotal clinical trials on mechanical thrombectomy for acute ischemic stroke randomized patients with isolated extracranial large vessel occlusions. On the contrary, several lines of evidence from non-randomized studies have shown that acute carotid endarterectomy, or endovascular thrombectomy/stenting of the ICA are feasible and safe, and pοtentially beneficial. The heterogeneity in the pathophysiology and clinical presentation of acute pICAOs renders patient selection for an acute interventional treatment a complicated decision-making process. The present narrative review will outline the pathophysiology, clinical presentation, diagnostic challenges, and possible treatment options for pICAOs.

Does prior administration of rtPA influence acute ischemic stroke clot composition? Findings from the analysis of clots retrieved with mechanical thrombectomy from the RESTORE registry.

BACKGROUND AND PURPOSE: There is still much debate whether bridging-therapy [intravenous thrombolysis (IVT) prior to mechanical thrombectomy (MT)] might be beneficial compared to MT alone. We investigated the effect of IVT on size and histological composition of the clots retrieved from patients undergoing bridging-therapy or MT alone. METHODS: We collected mechanically extracted thrombi from 1000 acute ischemic stroke (AIS) patients included in RESTORE registry. Patients were grouped according to the administration (or not) of IVT before thrombectomy. Gross photos of each clot were taken and Extracted Clot Area (ECA) was measured using ImageJ software. Martius Scarlett Blue stain was used to characterize the main histological clot components [red blood cells (RBCs), fibrin (FIB), platelets/other (PTL)] and Orbit Image Analysis was used for quantification. Additionally, we calculated the area of each main component by multiplying the component percent by ECA. Chi-squared and Kruskal-Wallis tests were used for statistical analysis. RESULTS: 451 patients (45%) were treated with bridging-therapy while 549 (55%) underwent MT alone. When considering only percent histological composition, we did not find any difference in RBC% (P = 0.895), FIB% (P = 0.458) and PTL% (P = 0.905). However, bridging-therapy clots were significantly smaller than MT-alone clots [32.7 (14.8-64.9) versus 36.8 (20.1-79.8) mm2, N = 1000, H1 = 7.679, P = 0.006*]. A further analysis expressing components per clot area showed that clots retrieved from bridging-therapy cases contained less RBCs [13.25 (4.29-32.06) versus 14.97 (4.93-39.80) mm2, H1 = 3.637, P = 0.056] and significantly less fibrin [9.10 (4.62-17.98) versus 10.54 (5.57-22.48) mm2, H1 = 7.920, P = 0.005*] and platelets/other [5.04 (2.26-11.32) versus 6.54 (2.94-13.79) mm2, H1 = 9.380, P = 0.002*] than MT-alone clots. CONCLUSIONS: Our results suggest that previous IVT administration significantly reduces thrombus size, proportionally releasing all the main histological components.

Correlation between acute ischaemic stroke clot length before mechanical thrombectomy and extracted clot area: Impact of thrombus size on number of passes for clot removal and final recanalization.

INTRODUCTION: We assessed the correlation between thrombus size before and after mechanical thrombectomy, measured as length by Computed Tomography Angiography/Non-Contrast Computed Tomography (CTA/NCCT) and Extracted Clot Area, ECA, respectively. We also assessed the influence of thrombus size on the number of passes required for clot removal and final recanalization outcome. MATERIALS AND METHODS: Acute ischaemic stroke (AIS) thrombi retrieved by mechanical thrombectomy from 500 patients and data of clot length by CTA/NCCT were collected from three hospitals in Europe. ECA was obtained by measuring the area of the extracted clot. Non-parametric tests were used for data analysis. RESULTS: A strong positive correlation was found between clot length on CTA/NCCT and ECA (rho = 0.619,N = 500,P < 0.0001*). Vessel size influences clot length on CTA/NCCT (H2 = 98.6, P < 0.0001*) and ECA (H2 = 105.6,P < 0.0001*), but the significant correlation between CTA/NCCT length and ECA was evident in all vessels. Poorer revascularisation outcome was associated with more passes (H5 = 73.1, P < 0.0001*). More passes were required to remove longer clots (CTA/NCCT; H4 = 31.4, P < 0.0001*; ECA; H4 = 50.2, P < 0.0001*). There was no significant main association between recanalization outcome and length on CTA/NCCT or ECA, but medium sized clots (ECA 20-40 mm2) were associated with least passes and highest revascularisation outcome (N = 500, X2 = 16.2, P < 0.0001*). CONCLUSION: Clot length on CTA/NCCT strongly correlates with ECA. Occlusion location influences clot size. More passes are associated with poorer revascularisation outcome and bigger clots. The relationship between size and revascularisation outcome is more complex. Clots of medium ECA take less passes to remove and are associated with better recanalization outcome than both smaller and larger clots.

Characterization of the 'White' Appearing Clots that Cause Acute Ischemic Stroke.

OBJECTIVES: Most clots retrieved from patients with acute ischemic stroke are 'red' in color. 'White' clots represent a less common entity and their histological composition is less known. Our aim was to investigate the composition, imaging and procedural characteristics of 'white' clots retrieved by mechanical thrombectomy. MATERIALS AND METHODS: Seventy five 'white' thrombi were selected by visual inspection from a cohort of 760 clots collected as part of the RESTORE registry. Clots were evaluated histopathologically. RESULTS: Quantification of Martius Scarlett Blue stain identified platelets/other as the major component in 'white' clots' (mean of 55% of clot overall composition) followed by fibrin (31%), red blood cells (6%) and white blood cells (3%). 'White' clots contained significantly more platelets/other (p<0.001*) and collagen/calcification (p<0.001*) and less red blood cells (p<0.001*) and white blood cells (p=0.018*) than 'red' clots. The mean platelet and von Willebrand Factor expression was 43% and 24%, respectively. Adipocytes were found in four cases. 'White' clots were significantly smaller (p=0.016*), less hyperdense (p=0.005*) on computed tomography angiography/non-contrast CT and were associated with a smaller extracted clot area (p<0.001*) than 'red' clots. They primarily caused the occlusion of middle cerebral artery, were less likely to be removed by aspiration and more likely to require rescue-therapy for retrieval. CONCLUSIONS: 'White' clots represented 14% of our cohort and were platelet, von Willebrand Factor and collagen/calcification-rich. 'White' clots were smaller, less hyperdense, were associated with significantly more distal occlusions and were less successfully removed by aspiration alone than 'red' clots.

Emerging agents for the treatment and prevention of stroke: progress in clinical trials.

INTRODUCTION: Recent years have witnessed unprecedented progress in stroke care, but unmet needs persist regarding the efficacy of acute treatment and secondary prevention. Novel approaches are being tested to enhance the efficacy of thrombolysis or provide neuroprotection in non-thrombolized patients. AREAS COVERED: The current review highlights pharmaceutical agents under evaluation in clinical trials concerning the acute, subacute, and chronic phase post-stroke. We examine the evidence in favor of tenecteplase as an alternative thrombolytic drug to alteplase, nerinetide as a promising neuroprotective agent, and glibenclamide for reducing edema in malignant hemispheric infarction. We discuss the use of ticagrelor and the promising novel category of factor XI inhibitors in the subacute phase after stroke. We offer our insights on combined rivaroxaban and antiplatelet therapy, PCSK-9 inhibitors, and other non-statin hypolipidemic agents, as well as novel antidiabetic agents that have been shown to reduce cardiovascular events in the long-term. EXPERT OPINION: Current approaches in stroke treatment and stroke prevention have already transformed stroke care from a linear one-for-all treatment paradigm to a more individualized approach that targets specific patient subgroups with novel pharmaceutical agents. This tendency enriches the therapeutic armamentarium with novel agents developed for specific stroke subgroups. ABBREVIATIONS: IVT: intravenous thrombolysis; RCTs: randomized-controlled clinical trials; TNK: Tenecteplase; COVID-19: Coronavirus 2019 Disease; EXTEND-IA TNK: The Tenecteplase versus Alteplase Before Endovascular Therapy for Ischemic Stroke trial; AIS: acute ischemic stroke; NNT: number needed to treat; MT: mechanical thrombectomy; sICH: symptomatic intracranial hemorrhage; mRS: modified Rankin Scale; AHA/ASA: American Heart Association/American Stroke Association; ESO: European Stroke Organization; NA-1: Nerinetide; ENACT: Evaluating Neuroprotection in Aneurysm Coiling Therapy; CTA: CT angiography; TIA: transient ischemic attack; CHANCE: Clopidogrel in High-risk patients with Acute Non-disabling Cerebrovascular Events; LOF: loss-of-function; PRINCE: Platelet Reactivity in Acute Nondisabling Cerebrovascular Events; THALES: Acute Stroke or Transient Ischemic Attack Treated with Ticagrelor and ASA [acetylsalicylic acid] for Prevention of Stroke and Death; CHANCE-2: Clopidogrel With Aspirin in High-risk Patients With Acute Non-disabling Cerebrovascular Events II; FXI: Factor XI; PACIFIC-STROKE: Program of Anticoagulation via Inhibition of FXIa by the Oral Compound BAY 2433334-NonCardioembolic Stroke study; COMPASS: Cardiovascular Outcomes for People Using Anticoagulation Strategies; CANTOS-ICAD: Combination Antithrombotic Treatment for Prevention of Recurrent Ischemic Stroke in Intracranial Atherosclerotic Disease; SAMMPRIS: Stenting and Aggressive Medical Therapy for Preventing Recurrent Stroke in Intracranial Stenosis; WASID: Warfarin-Aspirin Symptomatic Intracranial Disease; SPARCL: Stroke Prevention by Aggressive Reduction in Cholesterol Levels; LDL-C: low-density lipoprotein cholesterol; TST: Treat Stroke to Target; IMPROVE-IT: Improved Reduction of Outcomes: Vytorin Efficacy International Trial; PCSK9: proprotein convertase subtilisin-kexin type 9; FOURIER: Further Cardiovascular Outcomes Research with PCSK9 Inhibition in Subjects with Elevated Risk; CLEAR: Cholesterol Lowering via Bempedoic acid, an ACL-inhibiting Regimen; REDUCE-IT: Reduction of Cardiovascular Events With EPA Intervention Trial; STRENGTH: Outcomes Study to Assess STatin Residual Risk Reduction With EpaNova in HiGh CV Risk PatienTs With Hypertriglyceridemia; ACCORD: Action to Control Cardiovascular Risk in Diabetes; ADVANCE: Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation; VADT: Veterans Affairs Diabetes Trial; GLP-1R: Glucagon-like peptide-1 receptor; SGLT2: sodium-glucose cotransporter 2; CONVINCE: COlchicine for preventioN of Vascular Inflammation in Non-CardioEmbolic stroke; PROBE: Prospective Randomized Open-label Blinded Endpoint assessment.

Advanced Neuroimaging Preceding Intravenous Thrombolysis in Acute Ischemic Stroke Patients Is Safe and Effective.

Advanced neuroimaging is one of the most important means that we have in the attempt to overcome time constraints and expand the use of intravenous thrombolysis (IVT). We assessed whether, and how, the prior use of advanced neuroimaging (AN), and more specifically CT/MR perfusion post-processed with RAPID software, regardless of time from symptoms onset, affected the outcomes of acute ischemic stroke (AIS) patients who received IVT. Methods. We retrospectively evaluated consecutive AIS patients who received intravenous thrombolysis monotherapy (without endovascular reperfusion) during a six-year period. The study population was divided into two groups according to the neuroimaging protocol used prior to IVT administration in AIS patients (AN+ vs. AN-). Safety outcomes included any intracranial hemorrhage (ICH) and 3-month mortality. Effectiveness outcomes included door-to-needle time, neurological status (NIHSS-score) on discharge, and functional status at three months assessed by the modified Rankin Scale (mRS). Results. The rate of IVT monotherapy increased from ten patients per year (n = 29) in the AN- to fifteen patients per year (n = 47) in the AN+ group. Although the onset-to-treatment time was longer in the AN+ cohort, the two groups did not differ in door-to-needle time, discharge NIHSS-score, symptomatic ICH, any ICH, 3-month favorable functional outcome (mRS-scores of 0-1), 3-month functional independence (mRS-scores of 0-2), distribution of 3-month mRS-scores, or 3-month mortality. Conclusion. Our pilot observational study showed that the incorporation of advanced neuroimaging in the acute stroke chain pathway in AIS patients increases the yield of IVT administration without affecting the effectiveness and safety of the treatment.

Acute reperfusion therapies for acute ischemic stroke patients with unknown time of symptom onset or in extended time windows: an individualized approach.

Recent randomized controlled clinical trials (RCTs) have revolutionized acute ischemic stroke care by extending the use of intravenous thrombolysis and endovascular reperfusion therapies in time windows that have been originally considered futile or even unsafe. Both systemic and endovascular reperfusion therapies have been shown to improve outcome in patients with wake-up strokes or symptom onset beyond 4.5 h for intravenous thrombolysis and beyond 6 h for endovascular treatment; however, they require advanced neuroimaging to select stroke patients safely. Experts have proposed simpler imaging algorithms but high-quality data on safety and efficacy are currently missing. RCTs used diverse imaging and clinical inclusion criteria for patient selection during the dawn of this novel stroke treatment paradigm. After taking into consideration the dismal prognosis of nonrecanalized ischemic stroke patients and the substantial clinical benefit of reperfusion therapies in selected late presenters, we propose rescue reperfusion therapies for acute ischemic stroke patients not fulfilling all clinical and imaging inclusion criteria as an option in a subgroup of patients with clinical and radiological profiles suggesting low risk for complications, notably hemorrhagic transformation as well as local or remote parenchymal hemorrhage. Incorporating new data to treatment algorithms may seem perplexing to stroke physicians, since treatment and imaging capabilities of each stroke center may dictate diverse treatment pathways. This narrative review will summarize current data that will assist clinicians in the selection of those late presenters that will most likely benefit from acute reperfusion therapies. Different treatment algorithms are provided according to available neuroimaging and endovascular treatment capabilities.

Cervical duplex ultrasound for the diagnosis of giant cell arteritis with vertebral artery involvement.

Giant cell arteritis (GCA) is a systemic inflammatory arteriopathy of medium and large-sized arteries, predominantly affecting branches of the external carotid artery. Ischemic stroke has been reported in 2.8-7% of patients diagnosed with GCA. The majority of ischemic strokes may involve the posterior circulation as a result of vertebral and/or, less frequently, of basilar artery vasculitis. Prompt diagnosis is crucial since high-dose corticosteroid treatment is highly effective in preventing the occurrence or recurrence of ischemic complications, including posterior circulation ischemic stroke in cases with vertebrobasilar involvement. Cervical duplex sonography (CDS) of the temporal arteries is a powerful diagnostic tool with high sensitivity and specificity for the diagnosis of GCA. In cases with clinical suspicion or a temporal artery ultrasonographic confirmation of GCA, a detailed evaluation of the cervical, axillary, and intracranial arteries with CDS and transcranial-duplex-sonography, respectively, should be part of the ultrasound examination protocol. Specifically, signs of extracranial vertebral artery wall inflammation ("halo" sign) and focal luminar stenoses may be accurately depicted by ultrasounds in high-risk patients or individuals with ischemic stroke attributed to GCA. In this review, we present three cases of GCA and posterior circulation ischemic complications that were initially evaluated with comprehensive neurosonology protocol and were promptly diagnosed with GCA based on the characteristic "halo" sign in the temporal and vertebral arteries. In addition, we discuss the relevant literature concerning the utility of CDS for the early diagnosis of GCA, focusing on the subtype with extracranial arterial involvement, particularly that of the vertebral arteries.

Endovascular treatment for basilar artery occlusion: A systematic review and meta-analysis.

BACKGROUND AND PURPOSE: Independent randomized controlled clinical trials (RCTs) have provided robust evidence for endovascular treatment (EVT) as the standard of care treatment for acute large vessel occlusions in the anterior circulation. We examined available studies specific to posterior cerebral circulation ischemic strokes to see if any conclusions can be drawn regarding EVT options. METHODS: We performed a systematic literature search to identify studies evaluating the safety and efficacy of EVT versus standard medical treatment for patients with acute basilar artery occlusion (BAO). We extracted data for outcomes of interest and presented associations between the two groups with the use of risk ratios (RRs) or odds ratios (ORs), with corresponding 95% confidence intervals (CIs). We used a random-effects model to pool the effect estimates. RESULTS: We identified five studies (two RCTs, three observational cohorts) including a total of 1098 patients. Patients receiving EVT had a higher risk of symptomatic intracranial hemorrhage (sICH) compared to those receiving non-interventional medical management (RR 5.42, 95% CI 2.74-10.71). Nonsignificant trends towards modified Rankin Scale (mRS) scores 0-2 (RR 1.02, 95% CI 0.74-1.41), mRS scores 0-3 (RR = 0.97, 95% CI 0.64-1.47), overall functional improvement (OR 0.93, 95% CI 0.57-1.51), and all-cause mortality (RR 1.03, 95% CI 0.78-1.35) at 3 months were seen. CONCLUSION: Although EVT increases the probability of sICH, the available data do not exclude the possibility of improved functional outcomes over standard therapy. As larger studies are challenged by the perceived lack of equipoise in this vulnerable patient population, results of ongoing RCTs are expected to provide substantial input for future meta-analyses.

Real-world comparative safety and efficacy of tenecteplase versus alteplase in acute ischemic stroke patients with large vessel occlusion.

BACKGROUND AND AIMS: Tenecteplase has recently emerged as an alternative thrombolytic agent in acute ischemic stroke (AIS) patients with large vessel occlusion (LVO), possibly superior in achieving early reperfusion compared with alteplase. We aimed to compare the safety and efficacy of intravenous tenecteplase with intravenous alteplase for AIS patients with LVO in everyday clinical practice settings. METHODS: We prospectively evaluated patients with AIS due to LVO, treated with intravenous thrombolysis (IVT) with or without mechanical thrombectomy in two tertiary stroke centers. Patients were treated with standard-dose alteplase (0.9 mg/kg) or 0.25 mg/kg tenecteplase. Safety outcomes included prevalence of symptomatic intracranial hemorrhage (sICH) and mortality. Efficacy outcomes included averted thrombectomy, major neurological improvement at 24 h (defined as decrease in baseline NIHSS score of 8 points or greater) and functional status on discharge and on 3 months assessed by modified Rankin Scale (mRS). RESULTS: Nineteen AIS patients with LVO received tenecteplase and 39 received alteplase. We observed a non-significant higher rate of averted thrombectomies (32% versus 18%, p = 0.243) and a non-significant higher rate of sICH (16% versus 5%, p = 0.201) in the tenecteplase group. The rate of 24 h major neurological improvement was higher in the tenecteplase group (64% versus 33%, p = 0.046) but this was marginally attenuated in multivariable analyses (adjusted OR 10.22, 95% CI: 0.73-142.98; p = 0.084). Discharge mRS, 3-months mRS, and 3-month functional independence (mRS scores of 0-2) did not differ (p > 0.2) between the two groups. The rates of 3-month mortality (11% versus 18%, p = 0.703) were similar in the two groups. No independent association between thrombolytic agent and safety or efficacy outcomes emerged in multivariable regression analyses. CONCLUSION: The present pilot observational study highlights that AIS patients with LVO treated with 0.25 mg/kg bolus administration of tenecteplase had increased likelihood to achieve early neurological improvement compared with AIS patients treated with alteplase, but this association was attenuated after adjustment for potential confounders. There were no significant differences in 3-month functional or safety outcomes between the two groups. This preliminary real-world observation requires independent confirmation in larger, multicenter studies.

The administration of rtPA before mechanical thrombectomy in acute ischemic stroke patients is associated with a significant reduction of the retrieved clot area but it does not influence revascularization outcome.

Both intravenous thrombolysis (IVT) and mechanical thrombectomy (MT) are evidence-based treatments for acute ischemic stroke (AIS) in selected cases. Recanalization may occur following IVT without the necessity of further interventions or requiring a subsequent MT procedure. IVT prior to MT (bridging-therapy) may be associated with benefits or hazards. We studied the retrieved clot area and degree of recanalization in patients undergoing MT or bridging-therapy for whom it was possible to collect thrombus material. We collected mechanically extracted thrombi from 550 AIS patients from four International stroke centers. Patients were grouped according to the administration (or not) of IVT before thrombectomy and the mechanical thrombectomy approach used. We assessed the number of passes for clot removal and the mTICI (modified Treatment In Cerebral Ischemia) score to define revascularization outcome. Gross photos of each clot were taken and the clot area was measured with ImageJ software. The non-parametric Kruskal-Wallis test was used for statistical analysis. 255 patients (46.4%) were treated with bridging-therapy while 295 (53.6%) underwent MT alone. By analysing retrieved clot area, we found that clots from patients treated with bridging-therapy were significantly smaller compared to those from patients that underwent MT alone (H1 = 10.155 p = 0.001*). There was no difference between bridging-therapy and MT alone in terms of number of passes or final mTICI score. Bridging-therapy was associated with significantly smaller retrieved clot area compared to MT alone but it did not influence revascularization outcome.

Large Artery Atherosclerotic Clots are Larger than Clots of other Stroke Etiologies and have Poorer Recanalization rates.

OBJECTIVES: There is a paucity of knowledge in the literature relating to the extent of clot burden and stroke etiology. In this study, we measured the Extracted Clot Area (ECA) retrieved during endovascular treatment (EVT) and investigated relationships with suspected etiology, administration of intravenous thrombolysis and recanalization. MATERIALS AND METHODS: As part of the multi-institutional RESTORE registry, the ECA retrieved during mechanical thrombectomy was quantified using ImageJ. The effect of stroke etiology (Large-artery atherosclerosis (LAA), Cardioembolism, Cryptogenic and other) and recombinant tissue plasminogen activator (rtPA) on ECA and recanalization outcome (mTICI) was assessed. Successful recanalization was described as mTICI 2c-3. RESULTS: A total of 550 patients who underwent EVT with any clot retrieved were included in the study. The ECA was significantly larger in the LAA group compared to all other etiologies. The average ECA size of each etiology was; LAA=109 mm2, Cardioembolic=52 mm2, Cryptogenic=47 mm2 and Other=52 mm2 (p=0.014*). LAA patients also had a significantly poorer rate of successful recanalization (mTICI 2c-3) compared to all other etiologies (p=0.003*). The administration of tPA was associated with a smaller ECA in both LAA (p=0.007*) and cardioembolic (p=0.035*) groups. CONCLUSION: The ECA of LAA clots was double the size of all other etiologies and this is associated with a lower rate of successful recanalization in LAA stroke subtype. rtPA administration prior to thrombectomy was associated with reduced ECA in LAA and CE clots.