Rescue Therapy for Failed Mechanical Thrombectomy in Acute Ischemic Stroke: A Pooled Analysis of the Society of Vascular and Interventional Neurology Registry.

OBJECTIVE: We aimed to evaluate the association between rescue therapy (RT) and functional outcomes compared to medical management (MM) in patients presenting after failed mechanical thrombectomy (MT). METHODS: This cross-sectional study utilized prospectively collected and maintained data from the Society of Vascular and Interventional Neurology Registry, spanning from 2011 to 2021. The cohort comprised patients with large vessel occlusions (LVOs) with failed MT. The primary outcome was the shift in the degree of disability, as gauged by the modified Rankin Scale (mRS) at 90 days. Additional outcomes included functional independence (90-day mRS score of 0-2), symptomatic intracranial hemorrhage (sICH), and 90-day mortality. RESULTS: Of a total of 7,018 patients, 958 presented failed MT and were included in the analysis. The RT group comprised 407 (42.4%) patients, and the MM group consisted of 551 (57.5%) patients. After adjusting for confounders, the RT group showed a favorable shift in the overall 90-day mRS distribution (adjusted common odds ratio = 1.79, 95% confidence interval [CI] = 1.32-2.45, p < 0.001) and higher rates of functional independence (RT: 28.8% vs MM: 15.7%, adjusted odds ratio [aOR] = 1.93, 95% CI = 1.21-3.07, p = 0.005) compared to the MM group. RT also showed lower rates of sICH (RT: 3.8% vs MM: 9.1%, aOR = 0.52, 95% CI = 0.28-0.97, p = 0.039) and 90-day mortality (RT: 33.4% vs MM: 45.5%, aOR = 0.61, 95% CI = 0.42-0.89, p = 0.009). INTERPRETATION: Our findings advocate for the utilization of RT as a potential treatment strategy for cases of LVO resistant to first-line MT techniques. Prospective studies are warranted to validate these observations and optimize the endovascular approach for failed MT patients. ANN NEUROL 2024;96:343-355.

Global impact of COVID-19 on stroke care.

BACKGROUND: The COVID-19 pandemic led to profound changes in the organization of health care systems worldwide. AIMS: We sought to measure the global impact of the COVID-19 pandemic on the volumes for mechanical thrombectomy, stroke, and intracranial hemorrhage hospitalizations over a three-month period at the height of the pandemic (1 March-31 May 2020) compared with two control three-month periods (immediately preceding and one year prior). METHODS: Retrospective, observational, international study, across 6 continents, 40 countries, and 187 comprehensive stroke centers. The diagnoses were identified by their ICD-10 codes and/or classifications in stroke databases at participating centers. RESULTS: The hospitalization volumes for any stroke, intracranial hemorrhage, and mechanical thrombectomy were 26,699, 4002, and 5191 in the three months immediately before versus 21,576, 3540, and 4533 during the first three pandemic months, representing declines of 19.2% (95%CI, -19.7 to -18.7), 11.5% (95%CI, -12.6 to -10.6), and 12.7% (95%CI, -13.6 to -11.8), respectively. The decreases were noted across centers with high, mid, and low COVID-19 hospitalization burden, and also across high, mid, and low volume stroke/mechanical thrombectomy centers. High-volume COVID-19 centers (-20.5%) had greater declines in mechanical thrombectomy volumes than mid- (-10.1%) and low-volume (-8.7%) centers (p < 0.0001). There was a 1.5% stroke rate across 54,366 COVID-19 hospitalizations. SARS-CoV-2 infection was noted in 3.9% (784/20,250) of all stroke admissions. CONCLUSION: The COVID-19 pandemic was associated with a global decline in the volume of overall stroke hospitalizations, mechanical thrombectomy procedures, and intracranial hemorrhage admission volumes. Despite geographic variations, these volume reductions were observed regardless of COVID-19 hospitalization burden and pre-pandemic stroke/mechanical thrombectomy volumes.

Impact of Balloon Guide Catheter Use on Clinical and Angiographic Outcomes in the STRATIS Stroke Thrombectomy Registry.

Background and Purpose- Mechanical thrombectomy has been shown to improve clinical outcomes in patients with acute ischemic stroke. However, the impact of balloon guide catheter (BGC) use is not well established. Methods- STRATIS (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) was a prospective, multicenter study of patients with large vessel occlusion treated with the Solitaire stent retriever as first-line therapy. In this study, an independent core laboratory, blinded to the clinical outcomes, reviewed all procedures and angiographic data to classify procedural technique, target clot location, recanalization after each pass, and determine the number of stent retriever passes. The primary clinical end point was functional independence (modified Rankin Scale, 0-2) at 3 months as determined on-site, and the angiographic end point was first-pass effect (FPE) success rate from a single device attempt (modified Thrombolysis in Cerebral Infarction, ≥2c) as determined by a core laboratory. Achieving modified FPE (modified Thrombolysis in Cerebral Infarction, ≥2b) was also assessed. Comparisons of clinical outcomes were made between groups and adjusted for baseline and procedural characteristics. All participating centers received institutional review board approval from their respective institutions. Results- Adjunctive technique groups included BGC (n=445), distal access catheter (n=238), and conventional guide catheter (n=62). The BGC group had a higher rate of FPE following first pass (212/443 [48%]) versus conventional guide catheter (16/62 [26%]; P=0.001) and distal access catheter (83/235 [35%]; P=0.002). Similarly, the BGC group had a higher rate of modified FPE (294/443 [66%]) versus conventional guide catheter (26/62 [42%]; P<0.001) and distal access catheter (129/234 [55%]; P=0.003). The BGC group achieved the highest rate of functional independence (253/415 [61%]) versus conventional guide catheter (23/55 [42%]; P=0.007) and distal access catheter (113/218 [52%]; P=0.027). Final revascularization and mortality rates did not differ across the groups. Conclusions- BGC use was an independent predictor of FPE, modified FPE, and functional independence, suggesting that its routine use may improve the rates of early revascularization success and good clinical outcomes. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02239640.

Impact of Stent Retriever Size on Clinical and Angiographic Outcomes in the STRATIS Stroke Thrombectomy Registry.

Background and Purpose- The safety and efficacy of mechanical thrombectomy in patients with acute ischemic stroke has been demonstrated. However, the impact of stent retriever size on clinical and angiographic outcomes is not well established. Methods- This was a retrospective ad hoc analysis of data from the STRATIS (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) registry-a prospective, multicenter study of patients with large vessel occlusion treated with the Solitaire stent retriever. An independent core laboratory, blinded to clinical outcomes, reviewed all procedures and angiographic data to classify stent retriever size, targeted clot location, recanalization after each pass, and the number of stent retriever passes. The primary angiographic end point was first-pass effect (FPE) as determined by a core laboratory and defined as achieving near-complete revascularization (modified Thrombolysis in Cerebral Infarction ≥2c) after the first pass without the use of rescue therapy. Rates of modified FPE were also assessed, defined as meeting all criteria for FPE but achieving modified Thrombolysis in Cerebral Infarction ≥2b after first pass. The primary clinical end point was functional independence (modified Rankin Scale, 0-2) at 3 months as determined on-site. Outcome comparisons were made across the stent retriever size groups and adjusted for baseline characteristics. Results- Of 715 patients, a 4×20 stent retriever was used in 201 (28%) patients, 4×40 was used in 270 (38%) patients, and 6×30 was used in 244 (34%) patients. The 4×40 group had the highest rate of FPE ( P=0.003 versus 6×30) and modified FPE ( P=0.038 versus 4×20; P=0.0001 versus 6×30). Final revascularization was not significantly different across the groups, and there were no significant differences in functional dependence or mortality at 90 days post-procedure. Use of the longer stent retriever (4×40) was an independent predictor of achieving modified FPE ( P=0.037 versus 6×30; P=0.037 versus 4×20). Conclusions- The longer stent retriever (4×40) demonstrated the highest rate FPE and modified FPE compared with larger diameter or shorter stent retrievers, suggesting that their routine use may improve early revascularization success. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02239640.

Protocols for Endovascular Stroke Treatment Diminish the Weekend Effect Through Improvements in Off-Hours Care.

Introduction: The weekend effect is a well-recognized phenomenon in which patient outcomes worsen for acute strokes presenting outside routine business hours. This is attributed to non-uniform availability of services throughout the week and evenings and, though described for intravenous thrombolysis candidates, is poorly understood for endovascular stroke care. We evaluated the impact of institutional protocols on the weekend effect, and the speed and outcome of endovascular therapy as a function of time of presentation. Method: This study assesses a prospective observational cohort of 129 consecutive patients. Patients were grouped based on the time of presentation during regular work hours (Monday through Friday, 07:00-19:00 h) vs. off-hours (overnight 19:00-07:00 h and weekends) and assessed for treatment latency and outcome. Results: Treatment latencies did not depend on the time of presentation. The door to imaging interval was comparable during regular and off-hours (median time 21 vs. 19 min, respectively, p < 0.50). Imaging to groin puncture was comparable (71 vs. 71 min, p < 1.0), as were angiographic and functional outcomes. Additionally, treatment intervals decreased with increased protocol experience; door-to-puncture interval significantly decreased from the first to the fourth quarters of the study period (115 vs. 94 min, respectively, p < 0.006), with the effect primarily seen during off-hours with a 28% reduction in median door-to-puncture times. Conclusions: Institutional protocols help diminish the weekend effect in endovascular stroke treatment. This is driven largely by improvement in off-hours performance, with protocol adherence leading to further decreases in treatment intervals over time.

Thrombectomy 6 to 24 Hours after Stroke with a Mismatch between Deficit and Infarct.

BACKGROUND: The effect of endovascular thrombectomy that is performed more than 6 hours after the onset of ischemic stroke is uncertain. Patients with a clinical deficit that is disproportionately severe relative to the infarct volume may benefit from late thrombectomy. METHODS: We enrolled patients with occlusion of the intracranial internal carotid artery or proximal middle cerebral artery who had last been known to be well 6 to 24 hours earlier and who had a mismatch between the severity of the clinical deficit and the infarct volume, with mismatch criteria defined according to age (<80 years or ≥80 years). Patients were randomly assigned to thrombectomy plus standard care (the thrombectomy group) or to standard care alone (the control group). The coprimary end points were the mean score for disability on the utility-weighted modified Rankin scale (which ranges from 0 [death] to 10 [no symptoms or disability]) and the rate of functional independence (a score of 0, 1, or 2 on the modified Rankin scale, which ranges from 0 to 6, with higher scores indicating more severe disability) at 90 days. RESULTS: A total of 206 patients were enrolled; 107 were assigned to the thrombectomy group and 99 to the control group. At 31 months, enrollment in the trial was stopped because of the results of a prespecified interim analysis. The mean score on the utility-weighted modified Rankin scale at 90 days was 5.5 in the thrombectomy group as compared with 3.4 in the control group (adjusted difference [Bayesian analysis], 2.0 points; 95% credible interval, 1.1 to 3.0; posterior probability of superiority, >0.999), and the rate of functional independence at 90 days was 49% in the thrombectomy group as compared with 13% in the control group (adjusted difference, 33 percentage points; 95% credible interval, 24 to 44; posterior probability of superiority, >0.999). The rate of symptomatic intracranial hemorrhage did not differ significantly between the two groups (6% in the thrombectomy group and 3% in the control group, P=0.50), nor did 90-day mortality (19% and 18%, respectively; P=1.00). CONCLUSIONS: Among patients with acute stroke who had last been known to be well 6 to 24 hours earlier and who had a mismatch between clinical deficit and infarct, outcomes for disability at 90 days were better with thrombectomy plus standard care than with standard care alone. (Funded by Stryker Neurovascular; DAWN ClinicalTrials.gov number, NCT02142283 .).

Interhospital Transfer Before Thrombectomy Is Associated With Delayed Treatment and Worse Outcome in the STRATIS Registry (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke).

BACKGROUND: Endovascular treatment with mechanical thrombectomy (MT) is beneficial for patients with acute stroke suffering a large-vessel occlusion, although treatment efficacy is highly time-dependent. We hypothesized that interhospital transfer to endovascular-capable centers would result in treatment delays and worse clinical outcomes compared with direct presentation. METHODS: STRATIS (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) was a prospective, multicenter, observational, single-arm study of real-world MT for acute stroke because of anterior-circulation large-vessel occlusion performed at 55 sites over 2 years, including 1000 patients with severe stroke and treated within 8 hours. Patients underwent MT with or without intravenous tissue plasminogen activator and were admitted to endovascular-capable centers via either interhospital transfer or direct presentation. The primary clinical outcome was functional independence (modified Rankin Score 0-2) at 90 days. We assessed (1) real-world time metrics of stroke care delivery, (2) outcome differences between direct and transfer patients undergoing MT, and (3) the potential impact of local hospital bypass. RESULTS: A total of 984 patients were analyzed. Median onset-to-revascularization time was 202.0 minutes for direct versus 311.5 minutes for transfer patients (P<0.001). Clinical outcomes were better in the direct group, with 60.0% (299/498) achieving functional independence compared with 52.2% (213/408) in the transfer group (odds ratio, 1.38; 95% confidence interval, 1.06-1.79; P=0.02). Likewise, excellent outcome (modified Rankin Score 0-1) was achieved in 47.4% (236/498) of direct patients versus 38.0% (155/408) of transfer patients (odds ratio, 1.47; 95% confidence interval, 1.13-1.92; P=0.005). Mortality did not differ between the 2 groups (15.1% for direct, 13.7% for transfer; P=0.55). Intravenous tissue plasminogen activator did not impact outcomes. Hypothetical bypass modeling for all transferred patients suggested that intravenous tissue plasminogen activator would be delayed by 12 minutes, but MT would be performed 91 minutes sooner if patients were routed directly to endovascular-capable centers. If bypass is limited to a 20-mile radius from onset, then intravenous tissue plasminogen activator would be delayed by 7 minutes and MT performed 94 minutes earlier. CONCLUSIONS: In this large, real-world study, interhospital transfer was associated with significant treatment delays and lower chance of good outcome. Strategies to facilitate more rapid identification of large-vessel occlusion and direct routing to endovascular-capable centers for patients with severe stroke may improve outcomes. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02239640.

Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke: Primary Results of the STRATIS Registry.

BACKGROUND AND PURPOSE: Mechanical thrombectomy with stent retrievers has become standard of care for treatment of acute ischemic stroke patients because of large vessel occlusion. The STRATIS registry (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) aimed to assess whether similar process timelines, technical, and functional outcomes could be achieved in a large real world cohort as in the randomized trials. METHODS: STRATIS was designed to prospectively enroll patients treated in the United States with a Solitaire Revascularization Device and Mindframe Capture Low Profile Revascularization Device within 8 hours from symptom onset. The STRATIS cohort was compared with the interventional cohort of a previously published SEER patient-level meta-analysis. RESULTS: A total of 984 patients treated at 55 sites were analyzed. The mean National Institutes of Health Stroke Scale score was 17.3. Intravenous tissue-type plasminogen activator was administered in 64.0%. The median time from onset to arrival in the enrolling hospital, door to puncture, and puncture to reperfusion were 138, 72, and 36 minutes, respectively. The Core lab-adjudicated modified Thrombolysis in Cerebral Infarction ≥2b was achieved in 87.9% of patients. At 90 days, 56.5% achieved a modified Rankin Scale score of 0 to 2, all-cause mortality was 14.4%, and 1.4% suffered a symptomatic intracranial hemorrhage. The median time from emergency medical services scene arrival to puncture was 152 minutes, and each hour delay in this interval was associated with a 5.5% absolute decline in the likelihood of achieving modified Rankin Scale score 0 to 2. CONCLUSIONS: This largest-to-date Solitaire registry documents that the results of the randomized trials can be reproduced in the community. The decrease of clinical benefit over time warrants optimization of the system of care. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02239640.

Does the use of IV tPA in the current era of rapid and predictable recanalization by mechanical embolectomy represent good value?

As healthcare delivery in the USA transforms into a model that at its core requires value-based considerations, ischemic stroke is confronted by intersecting forces. Modern techniques allow rapid revascularization in the majority of patients with large vessel occlusions. Dramatic advances in the evidentiary basis for mechanical embolectomy are increasing the number of patients treated with this therapy. A key part of the therapeutic arsenal in many patients treated with interventional techniques has been concurrent intravenous thrombolysis. We consider whether this paradigm warrants change.

Stagnation of treatment times over a decade: results of a pooled analysis from the MERCI registry, MERCI, TREVO, and TREVO 2 trials.

BACKGROUND: There has been a growing interest in improving systems of care for the endovascular treatment of acute ischemic stroke. We analyzed data from previous registries and studies to determine if there has been an improvement in times to reperfusion with increasing experience. METHODS: We analyzed the pooled data from the Multi Mechanical Embolus Removal in Cerebral Ischemia (MERCI), MERCI Registry and Thrombectomy Revascularization of Large Vessel Occlusions (TREVO), and TREVO 2 trials and assessed times from last known normal to puncture, from hospital arrival to puncture, and procedure duration by year to determine if there has been a reduction in times. Demographic, radiographic, and clinical information were also assessed in a multivariate regression analysis to determine the predictors of good outcomes defined as a modified Rankin Scale score of 0-2 at 3 months. RESULTS: 1248 patients of mean age 68±14 years and median NIH Stroke Scale score 18 were analyzed from 2001 to 2011. Procedure times showed a significant improvement while last known normal to puncture times remained static. In multivariate logistic regression analysis, longer last known normal to puncture time and longer procedure duration were associated with a decreased chance of a good outcome (OR 0.84, 95% CI 0.76 to 0.92, p=0.0004 and OR 0.75, 95% CI 0.61 to 0.91, p=0.0040, respectively). CONCLUSIONS: Despite a reduction in procedure times, there has not been a corresponding improvement in overall last known normal to puncture times over a 10-year period. The current study shows that there are many opportunities to create more efficient endovascular stroke systems of care in trials.

Low neurologic intensive care unit hemoglobin as a predictor for intra-arterial vasospasm therapy and poor discharge modified Rankin Scale in aneurysmal subarachnoid haemorrhage-induced cerebral vasospasm.

BACKGROUND: Intra-arterial vasospasm therapy (IAVT) with vasodilators, balloon angioplasty, and cerebral blood flow augmentation devices are therapies for aneurysmal subarachnoid hemorrhage-induced symptomatic cerebral vasospasm refractory to maximal medical management. Our aim was to identify clinical factors predictive of IAVT and/or poor outcome. METHODS: A cross-sectional retrospective analysis was performed of 130 patients with aneurysmal subarachnoid hemorrhage including patients without and with symptomatic cerebral vasospasm requiring IAVT. The data were analysed by Student t test, univariate analysis and binary logistic regression. RESULTS: The mean±SD patient age was 54±12.2 years, admission hemoglobin was 13.6±1.5 g/dL, and neurologic intensive care unit (NICU) hemoglobin 11±1.4 g/dL. The median Hunt and Hess grade was 2 (range 1,4), Fisher grade 3 (range 3,3), and discharge modified Rankin Scale (mRS) 0.5 (range 0,2). Lower mean NICU hemoglobin was found in patients receiving IAVT than in those not receiving IAVT (M=10.4±0.9 g/dL vs M=11.2±1.4 g/dL, t(115)=-2.52, p=0.01). Further, lower mean NICU hemoglobin was associated with increased IAVT (ρ=-0.3, p<0.01) and higher discharge mRS (ρ=-0.5, p<0.01). In binary logistic regression, lower mean NICU hemoglobin was an independent predictor of IAVT (OR 0.6, 95% CI 0.4 to 0.9, p<0.05) as well as poor discharge mRS (OR 0.6, 95% CI 0.4 to 0.9, p<0.05). Hunt and Hess grade was also an independent predictor of these outcomes. CONCLUSIONS: Lower mean hemoglobin during the acute phase of aneurysmal subarachnoid hemorrhage-induced cerebral vasospasm is an independent predictor of IAVT and poor discharge mRS. This relationship warrants further evaluation.

Reducing door-to-puncture times for intra-arterial stroke therapy: a pilot quality improvement project.

BACKGROUND: Delays to intra-arterial therapy (IAT) lead to worse outcomes in stroke patients with proximal occlusions. Little is known regarding the magnitude of, and reasons for, these delays. In a pilot quality improvement (QI) project, we sought to examine and improve our door-puncture times. METHODS AND RESULTS: For anterior-circulation stroke patients who underwent IAT, we retrospectively calculated in-hospital time delays associated with various phases from patient arrival to groin puncture. We formulated and then implemented a process change targeted to the phase with the greatest delay. We examined the impact on time to treatment by comparing the pre- and post-QI cohorts. One hundred forty-six patients (93 pre- vs. 51 post-QI) were analyzed. In the pre-QI cohort (ie, sequential process), the greatest delay occurred from imaging to the neurointerventional (NI) suite ("picture-suite": median, 62 minutes; interquartile range [IQR], 40 to 82). A QI measure was instituted so that the NI team and anesthesiologist were assembled and the suite set up in parallel with completion of imaging and decision making. The post-QI (ie, parallel process) median picture-to-suite time was 29 minutes (IQR, 21 to 41; P<0.0001). There was a 36-minute reduction in median door-to-puncture time (143 vs. 107 minutes; P<0.0001). Parallel workflow and presentation during work hours were independent predictors of shorter door-puncture times. CONCLUSIONS: In-hospital delays are a major obstacle to timely IAT. A simple approach for achieving substantial time savings is to mobilize the NI and anesthesia teams during patient evaluation and treatment decision making. This parallel workflow resulted in a >30-minute (25%) reduction in median door-to-puncture times.

Predictors and outcomes of suspected heparin-induced thrombocytopenia in subarachnoid hemorrhage patients.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is a dreaded complication of heparin-related products and correlates with a worse outcome in aneurysmal subarachnoid hemorrhage (SAH) patients. OBJECTIVE: To study the risk factors and outcomes of SAH patients suspected of having HIT, confirmed as present or absent by the platelet factor 4 (PF4) antibody test. METHODS: All patients with presumed aneurysmal, nontraumatic SAH and having undergone a PF4 test were identified through our research patient database. Charts, laboratory values and images were analyzed retrospectively. RESULTS: We identified 166 patients with SAH who were tested for HIT; 42 patients (25%) had a positive antibody test. There was no difference in platelet profiles or mean platelet nadirs of HIT+ and HIT- patients (147 ± 93 vs. 153 ± 86 ×10(9)/l, respectively). Univariate analysis identified gender, magnesium prophylaxis, Fisher group 3, clipping versus coiling, presence of angiographic vasospasm, number of vasospasm treatments, and day of HIT testing as potential risk factors associated with HIT. A multivariate analysis indicated that female gender (OR 8.2, 95% CI 2.0-33.2), greater number of vasospasm treatments (OR 1.5, 95% CI 1.2-2.0), later day of HIT testing (OR 1.2, 95% CI 1.1-1.3), and clipping (OR 5.0, 95% CI 1.42-10.0) were independently associated with HIT positivity. HIT+ patients showed more infarcts on CT, longer ICU and hospital stays and worse modified Rankin Scale scores on discharge. CONCLUSION: The presence of HIT in SAH has adverse consequences and is more likely in female patients who have undergone aneurysm clipping and require multiple endovascular vasospasm treatments.

Clinical Outcome after Intra-Arterial Stroke Therapy in the Very Elderly: Why is it so Heterogeneous?

Very elderly patients (i.e., ≥80 years) are disproportionally affected by acute ischemic stroke. They account for a third of hospital stroke admissions, but two-thirds of overall stroke-related morbidity and mortality. There is some evidence of clinical benefit in treating selected very elderly patients with intravenous thrombolysis (IVT). For very elderly patients ineligible or non-responsive to IVT, intra-arterial therapy (IAT) may have promise in improving clinical outcome. However, its unequivocal efficacy in the general population remains to be proven in randomized trials. Small cohort studies reveal that the rate of good clinical outcome for very elderly patients after IAT is highly variable, ranging from 0 to 28%. In addition, they experience higher rates of futile reperfusion than younger patients. Thus, it is imperative to understand the factors that impact on clinical outcome in very elderly patients after IAT. The aim of this review is to examine the factors that may be responsible for the heterogeneous clinical response of the very elderly to IAT. This will allow the reader to integrate the current available evidence to individualize intra-arterial stroke therapy in very elderly patients. Placing emphasis on pre-stroke independent living, smaller infarct core size, short procedure times, and avoiding general anesthesia where feasible, will help improve rates of good clinical outcome.

Retrievable stent thrombectomy in the treatment of acute ischemic stroke: analysis of a revolutionizing treatment technique.

Acute ischemic stroke resulting from intracranial vessel occlusion is associated with high morbidity and mortality. The mainstays of therapy are fibrinolytics and mechanical thrombectomy in properly selected patients. A new Food and Drug Administration-approved technology to perform thrombectomy, retrievable stenting, may provide superior revascularization rates and improved patient outcomes. We analyzed the cumulative human experience reported for the Trevo Pro Retrieval System (Stryker, Kalamazoo, MI, USA) and the Solitaire FR Revascularization Device (ev3, Irvine, CA, USA) as the definitive treatment for acute ischemic stroke. A literature search was undertaken to identify studies using the retrievable stents published up to September 2012. Nineteen studies identified a total of 576 patients treated with either the Trevo (n=221) or Solitaire (n=355) devices. Pooled data analysis identified median baseline National Institutes of Health Stroke Scale scores of 18.5 ± 0.289 (standard error of the mean) and 17.9 ± 0.610, and time to recanalization of 53.9 ± 23.6 minutes and 59.0 ± 8.0 minutes for the Trevo and Solitaire groups, respectively. Recanalization was variably defined by individual studies, most commonly achieving at least a thrombolysis in cerebral infarction score of 2a-3 or a thrombolysis in myocardial infarction score of 2-3. Revascularization (83%, 82%), mortality (31%, 14%), hemorrhage (8%, 6%), device complications (5%, 6%), and good patient outcomes (51%, 47%) were found with the Trevo and Solitaire devices, respectively. Preliminary analysis reveals excellent clinical outcomes for retrievable stent technology. This may be attributable to both high rates of revascularization with a relatively short time to perfusion restoration.

Should clot composition affect choice of endovascular therapy?

Endovascular therapy has become a promising alternative for patients who are ineligible for IV thrombolysis or for whom it has failed. Greater knowledge about the composition of thromboembolic material underlying the vascular occlusion in stroke patients may provide the means for improving existing endovascular therapies and developing new treatment strategies. The objective of this article is to provide a review of clinical and experimental animal studies on the histology, imaging correlation, and ultrastructure of thromboemboli retrieved during acute ischemic stroke.