Mechanical Thrombectomy Global Access For Stroke (MT-GLASS): A Mission Thrombectomy (MT-2020 Plus) Study.

BACKGROUND: Despite the well-established potent benefit of mechanical thrombectomy (MT) for large vessel occlusion (LVO) stroke, access to MT has not been studied globally. We conducted a worldwide survey of countries on 6 continents to define MT access (MTA), the disparities in MTA, and its determinants on a global scale. METHODS: Our survey was conducted in 75 countries through the Mission Thrombectomy 2020+ global network between November 22, 2020, and February 28, 2021. The primary end points were the current annual MTA, MT operator availability, and MT center availability. MTA was defined as the estimated proportion of patients with LVO receiving MT in a given region annually. The availability metrics were defined as ([current MT operators×50/current annual number of estimated thrombectomy-eligible LVOs]×100 = MT operator availability) and ([current MT centers×150/current annual number of estimated thrombectomy-eligible LVOs]×100= MT center availability). The metrics used optimal MT volume per operator as 50 and an optimal MT volume per center as 150. Multivariable-adjusted generalized linear models were used to evaluate factors associated with MTA. RESULTS: We received 887 responses from 67 countries. The median global MTA was 2.79% (interquartile range, 0.70-11.74). MTA was <1.0% for 18 (27%) countries and 0 for 7 (10%) countries. There was a 460-fold disparity between the highest and lowest nonzero MTA regions and low-income countries had 88% lower MTA compared with high-income countries. The global MT operator availability was 16.5% of optimal and the MT center availability was 20.8% of optimal. On multivariable regression, country income level (low or lower-middle versus high: odds ratio, 0.08 [95% CI, 0.04-0.12]), MT operator availability (odds ratio, 3.35 [95% CI, 2.07-5.42]), MT center availability (odds ratio, 2.86 [95% CI, 1.84-4.48]), and presence of prehospital acute stroke bypass protocol (odds ratio, 4.00 [95% CI, 1.70-9.42]) were significantly associated with increased odds of MTA. CONCLUSIONS: Access to MT on a global level is extremely low, with enormous disparities between countries by income level. The significant determinants of MT access are the country's per capita gross national income, prehospital LVO triage policy, and MT operator and center availability.

Safety Outcomes of Mechanical Thrombectomy Versus Combined Thrombectomy and Intravenous Thrombolysis in Tandem Lesions.

BACKGROUND: We aimed to describe the safety and efficacy of mechanical thrombectomy (MT) with or without intravenous thrombolysis (IVT) for patients with tandem lesions and whether using intraprocedural antiplatelet therapy influences MT's safety with IVT treatment. METHODS: This is a subanalysis of a pooled, multicenter cohort of patients with acute anterior circulation tandem lesions treated with MT from 16 stroke centers between January 2015 and December 2020. Primary outcomes included symptomatic intracranial hemorrhage (sICH) and parenchymal hematoma type 2. Additional outcomes included hemorrhagic transformation, successful reperfusion (modified Thrombolysis in Cerebral Infarction score 2b-3), complete reperfusion (modified Thrombolysis in Cerebral Infarction score 3), favorable functional outcome (90-day modified Rankin Scale score 0-2), excellent functional outcome (90-day modified Rankin Scale score 0-1), in-hospital mortality, and 90-day mortality. RESULTS: Of 691 patients, 512 were included (218 underwent IVT+MT and 294 MT alone). There was no difference in the risk of sICH (adjusted odds ratio [aOR], 1.22 [95% CI, 0.60-2.51]; P=0.583), parenchymal hematoma type 2 (aOR, 0.99 [95% CI, 0.47-2.08]; P=0.985), and hemorrhagic transformation (aOR, 0.95 [95% CI, 0.62-1.46]; P=0.817) between the IVT+MT and MT alone groups after adjusting for confounders. Administration of IVT was associated with an increased risk of sICH in patients who received intravenous antiplatelet therapy (aOR, 3.04 [95% CI, 0.99-9.37]; P=0.05). The IVT+MT group had higher odds of a 90-day modified Rankin Scale score 0 to 2 (aOR, 1.72 [95% CI, 1.01-2.91]; P=0.04). The odds of successful reperfusion, complete reperfusion, 90-day modified Rankin Scale score 0 to 1, in-hospital mortality, or 90-day mortality did not differ between the IVT+MT versus MT alone groups. CONCLUSIONS: Our study showed that the combination of IVT with MT for tandem lesions did not increase the overall risk of sICH, parenchymal hematoma type 2, or overall hemorrhagic transformation independently of the cervical revascularization technique used. However, intraprocedural intravenous antiplatelet therapy during acute stent implantation might be associated with an increased risk of sICH in patients who received IVT before MT. Importantly, IVT+MT treatment was associated with a higher rate of favorable functional outcomes at 90 days.

Mechanical Thrombectomy for Large Vessel Occlusions in Cocaine Associated Acute Ischemic Stroke: Small Case Series and Review of the Literature.

INTRODUCTION: Cocaine through multifactorial pathogenetic mechanisms causes small and large vessel occlusions (LVO) leading to acute ischemic stroke. The optimal treatment for cocaine related LVO remains unknown. Mechanical thrombectomy (MT) poses a unique challenge, and successful MT are not widely reported. MATERIAL AND METHODS: We report three patients with no other risk factors and a common history of cocaine metabolites found on presentation drug screen who underwent MT for MCA occlusions with subsequent failed recanalization or vessel re-occlusion due to persistent thrombosis and severe vasospasm.Two patients initially had good revascularization but then developed severe vasospasm and reoccluded, and the remaining patient had persistent severe distal vasospasm. Rescue therapy either with balloon angioplasty with stent placement or intraarterial vasodilator was used in all patients and was ineffective. All patient had large hemispheric strokes and developed malignant cerebral edema requiring hemicraniectomy in two of them. We also did literature review and summarized previously reported cases of cocaine associated vasospasm in MT and other endovascular procedures. CONCLUSION: In this case series, cocaine induced vasospasm contributed to unsuccessful recanalization and reocclusion in patients undergoing MT with poor outcomes. Further studies are needed to ascertain strategies for improved outcomes in patients with LVO related to cocaine use.

Stent-retriever thrombectomy after intravenous t-PA vs. t-PA alone in stroke.

BACKGROUND: Among patients with acute ischemic stroke due to occlusions in the proximal anterior intracranial circulation, less than 40% regain functional independence when treated with intravenous tissue plasminogen activator (t-PA) alone. Thrombectomy with the use of a stent retriever, in addition to intravenous t-PA, increases reperfusion rates and may improve long-term functional outcome. METHODS: We randomly assigned eligible patients with stroke who were receiving or had received intravenous t-PA to continue with t-PA alone (control group) or to undergo endovascular thrombectomy with the use of a stent retriever within 6 hours after symptom onset (intervention group). Patients had confirmed occlusions in the proximal anterior intracranial circulation and an absence of large ischemic-core lesions. The primary outcome was the severity of global disability at 90 days, as assessed by means of the modified Rankin scale (with scores ranging from 0 [no symptoms] to 6 [death]). RESULTS: The study was stopped early because of efficacy. At 39 centers, 196 patients underwent randomization (98 patients in each group). In the intervention group, the median time from qualifying imaging to groin puncture was 57 minutes, and the rate of substantial reperfusion at the end of the procedure was 88%. Thrombectomy with the stent retriever plus intravenous t-PA reduced disability at 90 days over the entire range of scores on the modified Rankin scale (P<0.001). The rate of functional independence (modified Rankin scale score, 0 to 2) was higher in the intervention group than in the control group (60% vs. 35%, P<0.001). There were no significant between-group differences in 90-day mortality (9% vs. 12%, P=0.50) or symptomatic intracranial hemorrhage (0% vs. 3%, P=0.12). CONCLUSIONS: In patients receiving intravenous t-PA for acute ischemic stroke due to occlusions in the proximal anterior intracranial circulation, thrombectomy with a stent retriever within 6 hours after onset improved functional outcomes at 90 days. (Funded by Covidien; SWIFT PRIME ClinicalTrials.gov number, NCT01657461.).

Reocclusion after successful endovascular treatment in acute ischemic stroke: systematic review and meta-analysis.

BACKGROUND: Endovascular treatment (EVT) is the standard of care for selected patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). OBJECTIVE: To systematically review the available data on: (1) incidence, predictors, and outcomes of patients with reocclusion after successful EVT for AIS and, (2) the characteristics, complications, and outcomes of patients with reocclusion treated with repeated EVT (rEVT) within 30 days of the first procedure. METHODS: PubMed was searched (between January 2012 and April 2021) to identify studies reporting reocclusion following successful EVT (Thrombolysis in Cerebral Infarction ≥2b) in patients with AIS due to LVO. Pooled incidence of reocclusion per 100 patients with successful recanalization following EVT was calculated using a random-effects model with Freeman-Tukey double arcsine transformation. Extracted incidences of reocclusion according to etiology and use of intravenous thrombolysis were pooled using random-effects meta-analytic models. RESULTS: A total of 840 studies was identified and seven studies qualified for the quantitative analysis, which described 91 same-vessel reocclusions occurring within the first 7 days after treatment among 2067 patients (4.9%; 95% CI 3% to 7%, I2=70.2%). Large vessel atherosclerosis was associated with an increased risk of reocclusion (OR=3.44, 95% CI 1.12 to 10.61, I2=50%). We identified 90 patients treated with rEVT for recurrent LVO, described in five studies. The rates of procedural complications, mortality, and unfavorable functional outcome at 3 months were 18.0%, 18.9%, and 60.3%, respectively. CONCLUSION: In cohorts of patients with AIS due to LVO, 5% of patients experienced reocclusion within 7 days after successful EVT. Repeated EVT can be a safe and effective treatment for selected patients with reocclusion.

The SARS-CoV-2/COVID-19 pandemic and challenges in stroke care in India.

Stroke care in India has evolved rapidly in the last decade with a focus on stroke awareness, prevention, rapid triage, treatment, and rehabilitation. But acute stroke care and poststroke rehabilitation in the country have limitations owing to the economic constraints and poor access to health care. The SARS-CoV-2/COVID-19 pandemic has made stroke care even more challenging. We outline the unfavorable circumstances in stroke care induced by the pandemic; propose mitigating measures; crisis management; and provide a comparative evaluation of stroke care between India and the United States during the pandemic. There is a need for public health systems in both developed and developing countries to improve awareness, implement proper strategies of triage, acute treatment, well-defined rehabilitation plans, telemedicine services, and virtual check-ins.

Treatment and diagnosis of cerebral aneurysms in the post-International Subarachnoid Aneurysm Trial (ISAT) era: trends and outcomes.

BACKGROUND: Following publication of the International Subarachnoid Aneurysm Trial (ISAT), treatment paradigms for cerebral aneurysms (CAs) shifted from open surgical clipping to endovascular embolization as primary therapy in a majority of cases. However, comprehensive analyses evaluating more recent CA diagnosis patterns, patient populations and outcomes as a function of treatment modality remain rare. METHODS: The National Inpatient Sample from 2004 to 2014 was reviewed. Aneurysmal subarachnoid hemorrhages (aSAHs) and unruptured intracranial aneurysms (UIAs) with a treatment of surgical clipping or endovascular therapy (EVT) were identified. Time trend series plots were created. Linear and logistic regressions were utilized to quantify treatment changes. RESULTS: 114 137 aSAHs and 122 916 UIAs were reviewed. aSAH (+732/year, p=0.014) and UIA (+2550/year, p<0.0001) discharges increased annually. The annual caseload of surgical clippings for aSAH decreased (-264/year, p=0.0002) while EVT increased (+366/year, p=0.0003). For UIAs, the annual caseload for surgical clipping remained stable but increased for EVT (+615/year, p<0.0001). The rate of incidentally diagnosed UIAs increased annually (+1987/year; p<0.0001). Inpatient mortality decreased for clipping (p<0.0001) and EVT in aSAH (p<0.0001) (2004 vs 2014-clipping 13% vs 11.7%, EVT 15.8% vs 12.7%). Mortality rates for clipped UIAs decreased over time (p<0.0001) and remained stable for EVT (2004 vs 2014-clipping 1.57% vs 0.40%, EVT 0.59% vs 0.52%). CONCLUSION: Ruptured and unruptured CAs are increasingly being treated with EVT over clipping. Incidental unruptured aneurysm diagnoses are increasing dramatically. Mortality rates of ruptured aneurysms are improving regardless of treatment modality, whereas mortality in unruptured aneurysms is only improving for surgical clipping.

Carotid siphon calcification impact on revascularization and outcome in stroke intervention.

OBJECTIVE: The degree of coronary artery calcification has been shown to predict outcomes in coronary artery disease. The impact of intracranial carotid artery calcification on the prognosis of acute ischemic stroke (AIS) is unknown. The authors sought to examine if the degree of intracranial carotid artery calcification influences reperfusion or outcomes in AIS intervention. METHODS: All anterior circulation large vessel occlusion AIS cases that underwent intra-arterial therapy from January 2009 to July 2012 were reviewed. Clinical and radiographic data were collected. Non-contrast brain CT scans were assigned a Calcium Extent Score (degree of calcification of the carotid wall circumference), Calcium Thickness Score (thickness of the calcified plaque), and total Carotid Siphon Calcium (CSC) Score (8-point scale). RESULTS: One-hundred seventeen patients met inclusion criteria. The mean age was 65.4±15.6 years and 36% were male. Calcification was present in the intracranial carotid artery of 84 patients (71%). Inter-rater agreement for total CSC score was strong (Spearman's rho=0.883, p<0.001). The mean Calcium Extent Score was 1.5±1.3, Calcium Thickness Score 1.3±1.0 and total CSC Score 2.8±2.2. Reperfusion and mRS were not associated with CSC. Multivariate linear regression analysis revealed that older age, history of coronary disease and cervical internal carotid occlusion/near-occlusion were independently associated with higher total CSC scores. CONCLUSION: Extensive calcification on the intracranial carotid artery does not have impact on reperfusion or clinical outcomes in AIS patients undergoing endovascular therapy. Higher CSC scores are associated with coronary artery disease, increasing age and cervical internal carotid artery occlusion/near-occlusion.

Treatment of vertebral artery origin stenosis with anti-proliferative drug-eluting stents.

BACKGROUND: Vertebral artery origin stenosis is a known cause of stroke that is treatable with angioplasty and stenting. Previous studies have demonstrated that this technique is safe but is limited by high rates of in-stent stenosis. Anti-proliferative drug-eluting stents are an alternative for reducing in-stent stenosis at the vertebral artery origin. METHODS: This retrospective study included five consecutive patients treated with anti-proliferative drug-eluting stents. The patients' demographics, indications for treatment, procedural technique, and clinical and radiographic follow-up are presented along with a review of the literature. RESULTS: No peri-procedural complications occurred. One patient had a transient ischemic attack (TIA) during the follow-up period. No patients had hemodynamically significant (>50%) in-stent stenosis at follow-up. Among the 287 cases reported in the literature, there were two strokes (.7%), four TIAs (1.4%), and no procedurally related deaths. Among patients undergoing angiographic follow-up, 26% were found to have >50% in-stent stenosis. CONCLUSIONS: Anti-proliferative drug-eluting stents hold promise for reducing in-stent stenosis at the vertebral artery origin.

Recanalization of a symptomatic extracranial internal carotid artery near occlusion with proximal and distal protection: technical case report.

OBJECTIVE: To describe a novel approach to recanalizing symptomatic extracranial internal carotid artery near occlusion using proximal and distal emboli protection devices. METHODS: Patients presenting with symptomatic extracranial internal carotid artery near occlusion who underwent endovascular recanalization between October 2004 and July 2005 were included in this study. During these procedures, a 9-French Concentric Balloon Guide Catheter (Concentric Medical, Mountain View, CA) was advanced into the common carotid artery proximal to the site of occlusion. During the prestent angioplasty of the lesion, the proximal balloon was inflated and aspiration was performed. After initial angioplasty and before stent placement, a distal filter protection device was placed in the distal internal carotid artery. Stent placement and repeat angioplasty were performed with both protection devices active. All patients were placed on dual antiplatelet therapy. RESULTS: There were four patients treated with a mean age of 74 years; three of these four patients were men. All patients had signs of ischemia and carotid occlusion or near occlusion on noninvasive imaging. Three right internal carotid arteries were treated. All patients were successfully recanalized. No procedurally related complications or deaths occurred. CONCLUSION: This series demonstrates the feasibility of recanalization of symptomatic carotid artery occlusion or near occlusion using proximal and distal emboli protection devices. Such an approach may provide an added level of safety during carotid recanalization procedures.