Thrombectomy for Stroke in the Public Health Care System of Brazil.

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. In 12 public hospitals, patients with a proximal intracranial occlusion in the anterior circulation that could be treated within 8 hours after the onset of stroke symptoms were randomly assigned in a 1:1 ratio to receive standard care plus mechanical thrombectomy (thrombectomy group) or standard care alone (control group). The primary outcome was the score on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]) at 90 days. RESULTS: A total of 300 patients were enrolled, including 79 who had undergone thrombectomy during an open-label roll-in period. Approximately 70% in the two groups received intravenous alteplase. The trial was stopped early because of efficacy when 221 of a planned 690 patients had undergone randomization (111 to the thrombectomy group and 110 to the control group). The common odds ratio for a better distribution of scores on the modified Rankin scale at 90 days was 2.28 (95% confidence interval [CI], 1.41 to 3.69; P = 0.001), favoring thrombectomy. The percentage of patients with a score on the modified Rankin scale of 0 to 2, signifying an absence of or minor neurologic deficit, was 35.1% in the thrombectomy group and 20.0% in the control group (difference, 15.1 percentage points; 95% CI, 2.6 to 27.6). Asymptomatic intracranial hemorrhage occurred in 51.4% of the patients in the thrombectomy group and 24.5% of those in the control group; symptomatic intracranial hemorrhage occurred in 4.5% of the patients in each group. CONCLUSIONS: In this randomized trial conducted in the public health care system of Brazil, endovascular treatment within 8 hours after the onset of stroke symptoms in conjunction with standard care resulted in better functional outcomes at 90 days than standard care alone. (Funded by the Brazilian Ministry of Health; RESILIENT ClinicalTrials.gov number, NCT02216643.).

Site Experience and Outcomes in the Trevo Acute Ischemic Stroke (TRACK) Multicenter Registry.

Background and Purpose- It remains unclear how experience influences outcomes after the advent of stent retriever technology. We studied the relationship between site experience and outcomes in the Trevo Acute Ischemic Stroke multicenter registry. Methods- The 24 sites that enrolled patients in the Trevo Acute Ischemic Stroke registry were trichotomized into low-volume (<2 cases/month), medium-volume (2-4 cases/month), and high-volume centers (>4 cases/month). Baseline features, imaging, and clinical outcomes were compared across the 3 volume strata. A multivariable analysis was performed to assess whether outcomes were influenced by site volumes. Results- A total of 624 patients were included and distributed as low- (n=188 patients, 30.1%), medium- (n=175, 28.1%), and high-volume (n=261, 41.8%) centers. There were no significant differences in terms of age (mean, 66±16 versus 67±14 versus 65±15; P=0.2), baseline National Institutes of Health Stroke Scale (mean, 17.6±6.5 versus 16.8±6.5 versus 17.6±6.9; P=0.43), or occlusion site across the 3 groups. Median (interquartile range) times from stroke onset to groin puncture were 266 (181.8-442.5), 239 (175-389), and 336.5 (221.3-466.5) minutes in low-, medium-, and high-volume centers, respectively (P=0.004). Higher efficiency and better outcomes were seen in higher volume sites as demonstrated by shorter procedural times (median, 97 versus 67 versus 69 minutes; P<0.001), higher balloon guide catheter use (40% versus 36% versus 59%; P≤0.0001), and higher rates of good outcome (90-day modified Rankin Scale [mRS], ≤2; 39% versus 50% versus 53.4%; P=0.02). There were no appreciable differences in symptomatic intracranial hemorrhage or 90-day mortality. After adjustments in the multivariable analysis, there were significantly higher chances of achieving a good outcome in high- versus low-volume (odds ratio, 1.67; 95% CI, 1.03-2.7; P=0.04) and medium- versus low-volume (odds ratio, 1.75; 95% CI, 1.1-2.9; P=0.03) centers, but there were no significant differences between high- and medium-volume centers (P=0.86). Conclusions- Stroke center volumes significantly influence efficiency and outcomes in mechanical thrombectomy.

Beyond Large Vessel Occlusion Strokes: Distal Occlusion Thrombectomy.

BACKGROUND AND PURPOSE: Endovascular therapy is the standard of care for the treatment of proximal large vessel occlusion strokes. Its safety and efficacy in the treatment of distal intracranial occlusions has not been well studied. METHODS: The data that support the findings of this study are available from the corresponding author on reasonable request. Retrospective review of a prospectively collected endovascular database (2010-2015, n=949) for all patients with distal intracranial occlusions treated endovascularly. Distal occlusions were defined as any segment of the anterior cerebral artery (ACA), posterior cerebral artery, or occlusion at or distal to the middle cerebral artery (MCA)-M3 opercular segment. RESULTS: Distal occlusions were treated in 69 patients. The mean age was 66.7±15.8 and 57% were male. Patients (29 [42%]) received intravenous tPA (tissue-type plasminogen activator). The median preprocedure National Institutes of Health Stroke Scale score was 18 (interquartile range, 13-23). The distal occlusion was the primary treatment location in 45 patients, in 23 patients the distal occlusion was treated as a rescue strategy after successful treatment of a proximal large vessel occlusion strokes, and 1 patient had both primary and rescue treatment. The locations of the primary cases were MCA-M3 (n=21), ACA alone (n=8), ACA with a concomitant MCA-M1 or MCA-M2 (n=10), ACA with a concomitant MCA-M3 (n=3), and posterior cerebral artery (n=3). The locations of the rescue cases were MCA-M3 (n=11), ACA (n=7), posterior cerebral artery (n=4), and both MCA-M3 and ACA (n=1). There was a single patient with primary ACA and MCA-M2 occlusions treated, who then had a rescue MCA-M3 thrombectomy addressed after initial reperfusion. The most common treatment modalities used were stent-retrievers (n=37, 54%), intra-arterial tPA (n=36, 52%), and thromboaspiration (n=31, 45%). Near complete or complete reperfusion of the distal territory (modified Treatment In Cerebral Ischemia [mTICI] 2b-3) was achieved in 57 cases (83%). Three parenchymal hematomas (4%) occurred in the territory of the treated distal occlusion with 2 of these patients also receiving intravenous tPA. At 90 days, 21 patients (30%) had a modified Rankin Scale score of 0 to 2 and 14 (20%) had died. CONCLUSIONS: Distal intracranial occlusions can be treated safely and successfully with endovascular therapy. These results need to be corroborated by larger prospective controlled studies.

Cervical Carotid Pseudo-Occlusions and False Dissections: Intracranial Occlusions Masquerading as Extracranial Occlusions.

BACKGROUND AND PURPOSE: Pseudo-occlusion (PO) of the cervical internal carotid artery (ICA) refers to an isolated occlusion of the intracranial ICA that appears as an extracranial ICA occlusion on computed tomography angiography (CTA) or digital subtraction angiography because of blockage of distal contrast penetration by a stagnant column of unopacified blood. We aim to better characterize this poorly recognized entity. METHODS: Retrospective review of an endovascular database (2010-2015; n=898). Only patients with isolated intracranial ICA occlusions as confirmed by angiographic exploration were included. CTA and digital subtraction angiography images were categorized according to their apparent site of occlusion as (1) extracranial ICA PO or (2) discernible intracranial ICA occlusion. RESULTS: Cervical ICA PO occurred in 21/46 (46%) patients on CTA (17 proximal cervical; 4 midcervical). Fifteen (71%) of these patients also had PO on digital subtraction angiography. A flame-shaped PO mimicking a carotid dissection was seen in 7 (33%) patients on CTA and in 6 (29%) patients on digital subtraction angiography. Patients with and without CTA PO had similar age (64.8±17.1 versus 60.2±15.7 years; P=0.35), sex (male, 47% versus 52%; P=1.00), and intravenous tissue-type plasminogen activator use (38% versus 40%; P=1.00). The rates of modified Treatment In Cerebral Ischemia 2b-3 reperfusion were 71.4% in the PO versus 100% in the non-PO cohorts (P<0.01). The rates of parenchymal hematoma, 90-day modified Rankin Scale score 0-2, and 90-day mortality were 4.8% versus 8% (P=0.66), 40% versus 66.7% (P=0.12), and 25% versus 21% (P=0.77) in PO versus non-PO patients, respectively. Multivariate analysis indicated that PO patients had lower chances of modified Treatment In Cerebral Ischemia 3 reperfusion (odds ratio 0.14; 95% confidence interval 0.02-0.70; P=0.01). CONCLUSIONS: Cervical ICA PO is a relatively common entity and may be associated with decreased reperfusion rates.

Computed Tomographic Perfusion Selection and Clinical Outcomes After Endovascular Therapy in Large Vessel Occlusion Stroke.

BACKGROUND AND PURPOSE: Different imaging paradigms have been used to select patients for endovascular therapy in stroke. We sought to determine whether computed tomographic perfusion (CTP) selection improves endovascular therapy outcomes compared with noncontrast computed tomography alone. METHODS: Review of a prospectively collected registry of anterior circulation stroke patients undergoing stent-retriever thrombectomy at a tertiary care center between September 2010 and March 2016. Patients undergoing CTP were compared with those with noncontrast computed tomography alone. The primary outcome was the shift in the 90-day modified Rankin scale (mRS). RESULTS: A total of 602 patients were included. CTP-selected patients (n=365, 61%) were younger (P=0.02) and had fewer comorbidities. CTP selection (n=365, 61%) was associated with a favorable 90-day mRS shift (adjusted odds ratio [aOR]=1.49; 95% confidence interval [CI], 1.06-2.09; P=0.02), higher rates of good outcomes (90-day mRS score 0-2: 52.9% versus 40.4%; P=0.005), modified Thrombolysis in Cerebral Infarction-3 reperfusion (54.8% versus 40.1%; P<0.001), smaller final infarct volumes (24.7 mL [9.8-63.1 mL] versus 34.6 mL [13.1-88 mL]; P=0.017), and lower mortality (16.6% versus 26.8%; P=0.005). When matched on age, National Institutes of Health Stroke Scale (NIHSS) score, and glucose (n=424), CTP remained associated with a favorable 90-day mRS shift (P=0.016), lower mortality (P=0.02), and higher rates of reperfusion (P<0.001). CTP better predicted functional outcomes in patients presenting after 6 hours (as assessed by comparison of logistic regression models: Akaike information criterion: 199.35 versus 287.49 and Bayesian information criterion: 196.71 versus 283.27) and those with an Alberta Stroke Program Early Computed Tomography Score ≤7 (Akaike information criterion: 216.69 versus 334.96 and Bayesian information criterion: 213.6 versus 329.94). CONCLUSIONS: CTP selection is associated with a favorable mRS shift in patients undergoing stent-retriever thrombectomy. Future prospective studies are warranted.

Selection Paradigms for Large Vessel Occlusion Acute Ischemic Stroke Endovascular Therapy.

BACKGROUND: Optimal patient selection methods for thrombectomy in large vessel occlusion stroke (LVOS) are yet to be established. We sought to evaluate the ability of different selection paradigms to predict favorable outcomes. METHODS: Review of a prospectively collected database of endovascular patients with anterior circulation LVOS, adequate CT perfusion (CTP), National Institutes of Health Stroke Scale (NIHSS) ≥10 from September 2010 to March 2016. Patients were retrospectively assessed for thrombectomy eligibility by 4 mismatch criteria: Perfusion-Imaging Mismatch (PIM): between CTP-derived perfusion defect and ischemic core volumes; Clinical-Core Mismatch (CCM): between age-adjusted NIHSS and CTP core; Clinical-ASPECTS Mismatch (CAM-1): between age-adjusted NIHSS and ASPECTS; Clinical-ASPECTS Mismatch (CAM-2): between NIHSS and ASPECTS. Outcome measures were inclusion rates for each paradigm and their ability to predict good outcomes (90-day modified Rankin Scale 0-2). RESULTS: Three hundred eighty-four patients qualified. CAM-2 and CCM had higher inclusion (89.3 and 82.3%) vs. CAM-1 (67.7%) and PIM (63.3%). Proportions of selected patients were statistically different except for PIM and CAM-1 (p = 0.19), with PIM having the highest disagreement. There were no differences in good outcome rates between PIM(+)/PIM(-) (52.2 vs. 48.5%; p = 0.51) and CAM-2(+)/CAM-2(-) (52.4 vs. 38.5%; p = 0.12). CCM(+) and CAM-1(+) had higher rates compared to nonselected counterparts (53.4 vs. 38.7%, p = 0.03; 56.6 vs. 38.6%; p = 0.002). The abilities of PIM, CCM, CAM-1, and CAM-2 to predict outcomes were similar according to the c-statistic, Akaike and Bayesian information criterion. CONCLUSIONS: For patients with NIHSS ≥10, PIM appears to disqualify more patients without improving outcomes. CCM may improve selection, combining a high inclusion rate with optimal outcome discrimination across (+) and (-) patients. Future studies are warranted.

Large Volumes of Critically Hypoperfused Penumbral Tissue Do Not Preclude Good Outcomes After Complete Endovascular Reperfusion: Redefining Malignant Profile.

BACKGROUND AND PURPOSE: Acute ischemic stroke patients with large volumes of severe hypoperfusion (Tmax>10 s>100 mL) on magnetic resonance imaging have a higher likelihood of intracranial hemorrhage and poor outcomes after reperfusion. We aim to evaluate the impact of the extent of Tmax>10 s CTP lesions in patients undergoing successful treatment. METHODS: Retrospective database review of endovascular acute ischemic stroke treatment between September 2010 and March 2015 for patients with anterior circulation occlusions with baseline RAPID CTP and full reperfusion (mTICI 3). The primary outcome was the impact of the Tmax>10 s lesion spectrum on infarct growth. Secondary safety and efficacy outcomes included parenchymal hematomas and good clinical outcomes (90-day modified Rankin Scale score, 0-2). RESULTS: Of 684 treated patients, 113 patients fit the inclusion criteria. Tmax>10 s>100 mL patients (n=37) had significantly higher baseline National Institutes of Health Stroke Scale (20.7±3.8 versus 17.0±5.9; P<0.01), more internal carotid artery terminus occlusions (29% versus 9%; P=0.02), and larger baseline (38.6±29.6 versus 11.7±15.8 mL; P<0.01) and final (60.7±60.0 versus 29.4±33.9 mL; P<0.01) infarct volumes when compared with patients without Tmax>10 s>100 mL (n=76); however, the 2 groups were otherwise well balanced. There were no significant differences in infarct growth (22.1±51.6 versus 17.8±32.4 mL; P=0.78), severe intracranial hemorrhage (PH2: 2% versus 4%; P=0.73), good outcomes (90-day mRS score, 0-2: 56% versus 59%; P=0.83), or 90-day mortality (16% versus 7%; P=0.28). On multivariate analysis, only baseline National Institutes of Health Stroke Scale (odds ratio, 1.19; 95% confidence interval, 1.06-1.34; P<0.01) and baseline infarct core volume (odds ratio, 1.05; 95% confidence interval, 1.02-1.08; P<0.01) were independently associated with Tmax>10 s>100 mL. There was no association between Tmax>10 s>100 mL with any PH, good outcome, or infarct growth. CONCLUSIONS: In the setting of limited baseline ischemic cores, large Tmax>10 s lesions on computed tomographic perfusion do not seem to be associated with a higher risk of parenchymal hematomas and do not preclude good outcomes in patients undergoing endovascular reperfusion with contemporary technology.

Early Endovascular Treatment in Intravenous Tissue Plasminogen Activator-Ineligible Patients.

BACKGROUND AND PURPOSE: Intravenous tissue-type plasminogen activator (tPA) treatment in acute stroke has many exclusion criteria. We aimed to assess the safety and efficacy of endovascular therapy (ET) in intravenous (IV) tPA-ineligible patients. METHODS: Retrospective analysis of a prospectively collected database of consecutive patients treated with ET within 6 hours of stroke onset between September 2010 and April 2015. Patients treated with IV-tPA followed by ET were compared with those treated with ET alone because of IV-tPA ineligibility. Efficacy and safety end points included the rates of good outcome (90-day modified Rankin scale score ≤2), successful reperfusion (modified Treatment in Cerebral Ischemia 2b-3), parenchymal hematoma (PH-1 and PH-2), and 90-day mortality. Univariate and logistic regression were performed to identify the predictors of outcomes. RESULTS: A total of 422 patients were included. Two hundred and fifty-three (59%) patients received IV-tPA+ET, and 169 (41%), ET alone. Combined IV-tPA+ET patients were slightly younger (64.9±15.2 versus 67.9±14.9 years; P=0.05), more often males (56% versus 44%; P=0.01), and had less hypertension (70% versus 81%; P=0.02) and vertebrobasilar occlusions (3% versus 8%; P=0.02). The remaining baseline characteristics, including National Institutes of Health Stroke Scale score (20 [15-23] versus 19 [15-24]; P=0.85), Alberta Stroke Program Early CT Score (ASPECTS; 8 [7-9] versus 8 [7-9]; P=0.24), and stroke onset to puncture times (235±70 versus 240±81 minutes; P=0.27), were similar across both groups. There were no significant differences in the rates of modified Treatment in Cerebral Ischemia 2b-3 (83% versus 80%; P=0.52), 90-day modified Rankin scale score ≤2 (45% versus 38%; P=0.21), or any PH (3% versus 5%; P=0.21). Unadjusted 90-day mortality was higher with ET alone (21% versus 34%; P<0.01); however, IV-tPA ineligibility was not associated with modified Treatment in Cerebral Ischemia 2b-3, any PH, good outcome, or 90-day mortality on logistic regression. CONCLUSIONS: IV-tPA-eligible and -ineligible patients seem to have similar outcomes after early ET.

Automated CT Perfusion Ischemic Core Volume and Noncontrast CT ASPECTS (Alberta Stroke Program Early CT Score): Correlation and Clinical Outcome Prediction in Large Vessel Stroke.

BACKGROUND AND PURPOSE: The semiquantitative noncontrast CT Alberta Stroke Program Early CT Score (ASPECTS) and RAPID automated computed tomography (CT) perfusion (CTP) ischemic core volumetric measurements have been used to quantify infarct extent. We aim to determine the correlation between ASPECTS and CTP ischemic core, evaluate the variability of core volumes within ASPECTS strata, and assess the strength of their association with clinical outcomes. METHODS: Review of a prospective, single-center database of consecutive thrombectomies of middle cerebral or intracranial internal carotid artery occlusions with pretreatment CTP between September 2010 and September 2015. CTP was processed with RAPID software to identify ischemic core (relative cerebral blood flow<30% of normal tissue). RESULTS: Three hundred and thirty-two patients fulfilled inclusion criteria. Median age was 66 years (55-75), median ASPECTS was 8 (7-9), whereas median CTP ischemic core was 11 cc (2-27). Median time from last normal to groin puncture was 5.8 hours (3.9-8.8), and 90-day modified Rankin scale score 0 to 2 was observed in 54%. The correlation between CTP ischemic core and ASPECTS was fair (R=-0.36; P<0.01). Twenty-six patients (8%) had ASPECTS <6 and CTP core ≤50 cc (37% had modified Rankin scale score 0-2, whereas 29% were deceased at 90 days). Conversely, 27 patients (8%) had CTP core >50 cc and ASPECTS ≥6 (29% had modified Rankin scale 0-2, whereas 21% were deceased at 90 days). Moderate correlations between ASPECTS and final infarct volume (R=-0.42; P<0.01) and between CTP ischemic core and final infarct volume (R=0.50; P<0.01) were observed; coefficients were not significantly influenced by the time from stroke onset to presentation. Multivariable regression indicated ASPECTS ≥6 (odds ratio 4.10; 95% confidence interval, 1.47-11.46; P=0.01) and CTP core ≤50 cc (odds ratio 3.86; 95% confidence interval, 1.22-12.15; P=0.02) independently and comparably predictive of good outcome. CONCLUSIONS: There is wide variability of CTP-derived core volumes within ASPECTS strata. Patient selection may be affected by the imaging selection method.

Endovascular Therapy for Large Vessel Stroke in the Elderly: Hope in the New Stroke Era.

BACKGROUND AND PURPOSE: Acute ischemic stroke (AIS) in the elderly encompasses approximately one-third of all AIS cases. Outcome data have been for the most part discouraging in this population. We aim to evaluate the outcomes in a large contemporary series of elderly patients treated with thrombectomy. METHODS: Retrospective analysis of a single-center endovascular database for consecutive elderly (≥80 years) patients treated for anterior circulation large vessel occlusion AIS between September 2010 and April 2015. Univariate- and multivariate analyses were performed to identify the predictors of good clinical outcome (90-day modified Ranking Scale [mRS] ≤2). Receiver operating characteristic curves were used to calculate the optimal final infarct volume (FIV) threshold to predict good outcomes. RESULTS: A total of 111 patients met our inclusion criteria (mean age 84.8 ± 4.2 years; National Institutes of Health Stroke Scale [NIHSS] score 19.1 ± 5.6; time from last-known normal to puncture, 349.6 ± 246.6 min; 33% male; 68% Alberta Stroke Program Early CT Score [ASPECTS] ≥8). The rates of successful reperfusion (modified treatment in cerebral ischemia ≥2b), symptomatic intracranial hemorrhage and 90-day mortality were 80%, 7% and 41%, respectively. The overall rate of good outcome was 29% (n = 32/111) but was 52% (n = 13/25) in patients with baseline mRS score of 0-2 who were selected based on CT perfusion and treated with stent retrievers. On multivariate analysis, only ASPECTS (OR 2.17; 95% CI 1.28-3.67.7; p = 0.004) and baseline NIHSS score (OR 0.87; 95% CI 0.77-0.97; p = 0.013) were independently associated with good outcome. A FIV ≤16 ml demonstrated the greatest accuracy for identifying good outcomes (sensitivity 75.0%, specificity 82.6%). CONCLUSIONS: Our results are encouraging demonstrating nearly one-third of elderly patients achieving full independence at 90 days. Contemporary treatment paradigms employing optimized patient selection and modern thrombectomy technology may result in even better outcomes.

Endovascular Treatment of Acute Ischemic Stroke Due to Tandem Occlusions: Large Multicenter Series and Systematic Review.

BACKGROUND: Ischemic strokes due to tandem occlusions (TOs) have poor outcomes if they have been treated with only medical interventions. Recent trials demonstrated the effectiveness of endovascular treatment of acute ischemic stroke due to intracranial occlusions; however, most studies excluded patients with TOs. METHODS: Retrospective review of prospectively collected thrombectomy databases from 3 stroke centers between 2011 and 2015. Consecutive patients with tandem extracranial steno-occlusive carotid disease and intracranial occlusions who underwent emergent thrombectomy were selected. Angiographic and clinical outcomes were analyzed; baseline and procedural variables were included in univariate and multivariate analyses to define the independent predictors of good outcomes (90-day modified Rankin Scale ≤2). RESULTS: A total of 100 patients met the study inclusion criteria. The mean age was 64.4 ± 12.5, baseline National Institutes of Health Stroke Scale (NIHSS) 17.6 ± 5.0, time from last known well to puncture 7.3 ± 5.8 h, and Alberta Stroke Program Early CT Score (ASPECTS) 7.5 ± 1.6. Forty percent received intravenous tissue plasminogen activator. Intracranial occlusion sites included: internal carotid artery thrombus, 31%; middle cerebral artery (MCA)-M1, 53%; MCA-M2, 10%; and anterior cerebral artery, 6%. Good outcome was achieved in 42% and successful reperfusion modified thrombolysis in cerebral infarction (mTICI ≥2B) in 88% of the cases, including complete (mTICI 3) reperfusion in 40%. Severe parenchymal hematoma (PH)-2 occurred in 6% of the patients and 90-day mortality was 20%. In the multivariate analysis, younger age (OR 0.93; 95% CI 0.88-0.98; p = 0.004), lower baseline NIHSS (OR 0.84; 95% CI 0.74-0.94; p = 0.003), higher ASPECTS (OR 1.50; 95% CI 1.02-2.19; p = 0.038), and mTICI 3 reperfusion (OR 3.56; 95% CI 1.18-10.76; p = 0.024) were independent predictors of good outcome at 90 days. CONCLUSIONS: Acute endovascular treatment of tandem anterior circulation occlusions yields good outcomes and has similar outcome predictors to isolated intracranial occlusions. Given their comparable clinical behavior, these patients should be included in future trials.

Optimizating Clot Retrieval in Acute Stroke: The Push and Fluff Technique for Closed-Cell Stentrievers.

BACKGROUND AND PURPOSE: We aimed to investigate the safety and efficacy of the Push and Fluff technique (PFT) as compared with the standard unsheathing technique for closed-cell stent retrievers in acute ischemic stroke. METHODS: Acute ischemic stroke thrombectomy database was analyzed (September 2010 to January 2015) with the Trevo Retriever as a primary strategy. The PFT was compared with our internal standard unsheathing technique and with the Trevo Versus Merci Retrievers for Thrombectomy Revascularization of Large Vessel Occlusions in Acute Ischemic Stroke 2 (TREVO2) trial. Additionally, a silicon flow model was used to compare cell size/configuration, wall apposition/device diameter, and degree of foreshortening/device length across the 2 techniques. RESULTS: One hundred fifty-one out of 662 patients qualified for the study. The PFT (n=71) was associated with higher rates of first-pass reperfusion (54% versus 35%, P=0.03; 54% versus 32.6%, P<0.01), lower number of passes (1.3±0.8 versus 1.8±1.0, P<0.01; 1.7±1.0 versus 2.4±1.6, P<0.01), and higher rates of modified treatment in cerebral ischemia-3 reperfusion (58% versus 40%, P=0.03; 58% versus 14%, P<0.01) as compared with the standard unsheathing technique (n=81) and the TREVO2 Trevo arm (n=88), respectively. No differences in hemorrhagic complications were observed across the groups. The in vitro model indicated that, compared with standard unsheathing technique, PFT resulted in improved wall apposition (device diameter, 75% larger) and cell size (mean area, 51% larger) at the cost of a mild degree of foreshortening (25% length reduction). CONCLUSIONS: The PFT is safe and leads to optimization of wall apposition and cell size/configuration, resulting in higher chances of first-pass reperfusion, lower number of passes, and better rates of complete reperfusion.

Endovascular Treatment for Acute Ischemic Stroke in the Setting of Anticoagulation.

BACKGROUND AND PURPOSE: Oral anticoagulation (OAC) plays a major role in atrial fibrillation stroke prevention but represents a contraindication to intravenous tissue-type plasminogen activator. Intra-arterial therapy remains a potential reperfusion strategy in these patients; however, supporting data are scarce. METHODS: Retrospective analysis of prospectively collected consecutive intra-arterial therapies from October 2010 to March 2015 comparing OAC (vitamin-K antagonists and novel oral anticoagulants) versus normal hemostasis versus intravenous tissue-type plasminogen activator patients. Primary safety end point is parenchymal hematoma. Secondary safety end point is 90-day mortality. Efficacy end points are successful reperfusion (modified Thrombolysis in Cerebral Infarction, 2b-3) and good outcome (90-day modified Rankin Scale score of 0-2). Logistic regression for predictors of parenchymal hematoma was performed. RESULTS: A total of 604 patients were qualified for the study. Baseline and outcomes variables were overall similar for vitamin-K antagonists (n=29) and novel oral anticoagulants (n=17) patients. When compared with normal hemostasis (n=265) and intravenous tissue-type plasminogen activator (n=297), OAC (n=46) patients were older and had more comorbidities. There were no statistically significant differences in the rates of parenchymal hematoma (8% versus 5%; P=0.42), 90-day modified Rankin Scale score of 0 to 2 (30% versus 40%; P=0.26), and 90-day mortality (32% versus 26%; P=0.46) among OAC and normal hemostasis patients. Similarly, there were no significant differences between OAC and intravenous tissue-type plasminogen activator patients in terms of parenchymal hematoma (8% versus 4%; P=0.16), 90-day modified Rankin Scale score of 0 to 2 (30% versus 43%; P=0.13), and 90-day mortality (32% versus 22%; P=0.18). The use of OAC was not associated with the occurrence of parenchymal hematoma on multivariate logistic regression analysis. CONCLUSIONS: Intra-arterial therapy seems to be safe in patients taking OACs; however, our study showed a nonsignificant increase in hemorrhage and mortality with a nonsignificant decrease in good outcomes in comparison with non-OAC patients. Although these nominal differences may have been related to older age and more comorbidities in the OAC group, larger studies are needed to confirm our findings given our limited sample size.

Global Impact of the COVID-19 Pandemic on Stroke Volumes and Cerebrovascular Events: A 1-Year Follow-up.

BACKGROUND AND OBJECTIVES: Declines in stroke admission, IV thrombolysis (IVT), and mechanical thrombectomy volumes were reported during the first wave of the COVID-19 pandemic. There is a paucity of data on the longer-term effect of the pandemic on stroke volumes over the course of a year and through the second wave of the pandemic. We sought to measure the effect of the COVID-19 pandemic on the volumes of stroke admissions, intracranial hemorrhage (ICH), IVT, and mechanical thrombectomy over a 1-year period at the onset of the pandemic (March 1, 2020, to February 28, 2021) compared with the immediately preceding year (March 1, 2019, to February 29, 2020). METHODS: We conducted a longitudinal retrospective study across 6 continents, 56 countries, and 275 stroke centers. We collected volume data for COVID-19 admissions and 4 stroke metrics: ischemic stroke admissions, ICH admissions, IVT treatments, and mechanical thrombectomy procedures. Diagnoses were identified by their ICD-10 codes or classifications in stroke databases. RESULTS: There were 148,895 stroke admissions in the 1 year immediately before compared with 138,453 admissions during the 1-year pandemic, representing a 7% decline (95% CI [95% CI 7.1-6.9]; p < 0.0001). ICH volumes declined from 29,585 to 28,156 (4.8% [5.1-4.6]; p < 0.0001) and IVT volume from 24,584 to 23,077 (6.1% [6.4-5.8]; p < 0.0001). Larger declines were observed at high-volume compared with low-volume centers (all p < 0.0001). There was no significant change in mechanical thrombectomy volumes (0.7% [0.6-0.9]; p = 0.49). Stroke was diagnosed in 1.3% [1.31-1.38] of 406,792 COVID-19 hospitalizations. SARS-CoV-2 infection was present in 2.9% ([2.82-2.97], 5,656/195,539) of all stroke hospitalizations. DISCUSSION: There was a global decline and shift to lower-volume centers of stroke admission volumes, ICH volumes, and IVT volumes during the 1st year of the COVID-19 pandemic compared with the prior year. Mechanical thrombectomy volumes were preserved. These results suggest preservation in the stroke care of higher severity of disease through the first pandemic year. TRIAL REGISTRATION INFORMATION: This study is registered under NCT04934020.

Global Impact of the COVID-19 Pandemic on Cerebral Venous Thrombosis and Mortality.

BACKGROUND AND PURPOSE: Recent studies suggested an increased incidence of cerebral venous thrombosis (CVT) during the coronavirus disease 2019 (COVID-19) pandemic. We evaluated the volume of CVT hospitalization and in-hospital mortality during the 1st year of the COVID-19 pandemic compared to the preceding year. METHODS: We conducted a cross-sectional retrospective study of 171 stroke centers from 49 countries. We recorded COVID-19 admission volumes, CVT hospitalization, and CVT in-hospital mortality from January 1, 2019, to May 31, 2021. CVT diagnoses were identified by International Classification of Disease-10 (ICD-10) codes or stroke databases. We additionally sought to compare the same metrics in the first 5 months of 2021 compared to the corresponding months in 2019 and 2020 (ClinicalTrials.gov Identifier: NCT04934020). RESULTS: There were 2,313 CVT admissions across the 1-year pre-pandemic (2019) and pandemic year (2020); no differences in CVT volume or CVT mortality were observed. During the first 5 months of 2021, there was an increase in CVT volumes compared to 2019 (27.5%; 95% confidence interval [CI], 24.2 to 32.0; P<0.0001) and 2020 (41.4%; 95% CI, 37.0 to 46.0; P<0.0001). A COVID-19 diagnosis was present in 7.6% (132/1,738) of CVT hospitalizations. CVT was present in 0.04% (103/292,080) of COVID-19 hospitalizations. During the first pandemic year, CVT mortality was higher in patients who were COVID positive compared to COVID negative patients (8/53 [15.0%] vs. 41/910 [4.5%], P=0.004). There was an increase in CVT mortality during the first 5 months of pandemic years 2020 and 2021 compared to the first 5 months of the pre-pandemic year 2019 (2019 vs. 2020: 2.26% vs. 4.74%, P=0.05; 2019 vs. 2021: 2.26% vs. 4.99%, P=0.03). In the first 5 months of 2021, there were 26 cases of vaccine-induced immune thrombotic thrombocytopenia (VITT), resulting in six deaths. CONCLUSIONS: During the 1st year of the COVID-19 pandemic, CVT hospitalization volume and CVT in-hospital mortality did not change compared to the prior year. COVID-19 diagnosis was associated with higher CVT in-hospital mortality. During the first 5 months of 2021, there was an increase in CVT hospitalization volume and increase in CVT-related mortality, partially attributable to VITT.

Basilar artery occlusion management: An international survey of middle versus high-income countries.

BACKGROUND AND PURPOSE: Two early basilar artery occlusion (BAO) randomized controlled trials (RCTs) did not establish the superiority of endovascular thrombectomy (EVT) over medical management. Yet many providers continued to recommend EVT. The goal of the present article is to compare physicians' diagnostic and management strategies of BAO among middle-income and high-income countries (MICs and HICs, respectively). METHODS: We conducted an international survey from January to March 2022 regarding management strategies in acute BAO, to examine clinical and imaging parameters influencing clinician management of patients with BAO. We compared responses between physicians from HIC and MIC. RESULTS: Among the 1245 respondents from 73 countries, 799 (64.2%) were from HIC, with the remaining 393 (31.6%) from MIC. Most respondents perceived that EVT was superior to medical management for acute BAO, but more so in respondents from HIC (98.0% vs. 94.2%, p < 0.01). MIC respondents were more likely to believe further RCTs were warranted (91.6% vs. 74.0%, p < 0.01) and were more likely to find it acceptable to enroll any patient who met a trial's criteria in the standard medical treatment arm (58.8% vs. 38.5%, p < 0.01). CONCLUSIONS: In an area where clinical equipoise was called into question despite the lack of RCT evidence, we found that respondents from MIC were more likely to express willingness to enroll patients with BAO in an RCT than their HIC counterparts.

Assessment of Optimal Patient Selection for Endovascular Thrombectomy Beyond 6 Hours After Symptom Onset: A Pooled Analysis of the AURORA Database.

Importance: The optimal imaging approach for identifying patients who may benefit from endovascular thrombectomy (EVT) beyond 6 hours after they were last known well is unclear. Six randomized clinical trials (RCTs) have evaluated the efficacy of EVT vs standard medical care among patients with ischemic stroke. Objective: To assess the benefits of EVT among patients with 3 baseline imaging profiles using a pooled analysis of RCTs. Data Sources: The AURORA (Analysis of Pooled Data from Randomized Studies of Thrombectomy More Than 6 Hours After Last Known Well) Collaboration pooled patient-level data from the included clinical trials. Study Selection: An online database search identified RCTs of endovascular stroke therapy published between January 1, 2010, and March 1, 2021, that recruited patients with ischemic stroke who were randomized between 6 and 24 hours after they were last known well. Data Extraction/Synthesis: Data from the final locked database of each study were provided. Data were pooled, and analyses were performed using mixed-effects modeling with fixed effects for parameters of interest. Main Outcomes and Measures: The primary outcome was reduction in disability measured by the modified Rankin Scale at 90 days. An evaluation was also performed to examine whether the therapeutic response differed based on imaging profile among patients who received treatment based on the time they were last known well. Treatment benefits were assessed among a clinical mismatch subgroup, a target perfusion mismatch subgroup, and an undetermined profile subgroup. The primary end point was assessed among these subgroups and during 3 treatment intervals (tercile 1, 360-574 minutes [6.0-9.5 hours]; tercile 2, 575-762 minutes [9.6-12.7 hours]; and tercile 3, 763-1440 minutes [12.8-24.0 hours]). Results: Among 505 eligible patients, 266 (mean [SD] age, 68.4 [13.8] years; 146 women [54.9%]) were assigned to the EVT group and 239 (mean [SD] age, 68.7 [13.7] years; 126 men [52.7%]) were assigned to the control group. Among 295 patients in the clinical mismatch subgroup and 359 patients in the target perfusion mismatch subgroup, EVT was associated with reductions in disability at 90 days vs no EVT (clinical mismatch subgroup, odds ratio [OR], 3.57; 95% CI, 2.29-5.57; P < .001; target perfusion mismatch subgroup, OR, 3.13; 95% CI, 2.10-4.66; P = .001). Statistically significant benefits were observed in all 3 terciles for both subgroups, with the highest OR observed for tercile 3 (clinical mismatch subgroup, OR, 4.95; 95% CI, 2.20-11.16; P < .001; target perfusion mismatch subgroup, OR, 5.01; 95% CI, 2.37-10.60; P < .001). A total of 132 patients (26.1%) had an undetermined imaging profile and no significant treatment benefit (OR, 1.59; 95% CI, 0.82-3.06; P = .17). The interaction between treatment effects for the clinical and target perfusion mismatch subgroups vs the undetermined profile subgroup was significant (OR, 2.28; 95% CI, 1.11-4.70; P = .03). Conclusions and Relevance: In this study, EVT was associated with similar benefit among patients in the clinical mismatch and target perfusion mismatch subgroups during the 6- to 24-hour treatment interval. These findings support EVT as a treatment for patients meeting the criteria for either of the imaging mismatch profiles within the 6- to 24-hour interval.

Endovascular management of acute large vessel occlusion stroke in pregnancy is safe and feasible.

INTRODUCTION: Stroke is a leading cause of adult death and disability. Although acute ischemic stroke (AIS) in pregnancy is rare, it has devastating consequences on the life of the mother and fetus. Pregnancy was an exclusion criterion in endovascular thrombectomy (EVT) trials and so there are no evidence-based treatment recommendations in this subgroup. The objective of this study was to evaluate the safety and feasibility of mechanical thrombectomy in large vessel occlusion (LVO) stroke in pregnancy. METHODS: Patients with AIS due to LVO treated with EVT during pregnancy between 2000 and 2019 were identified at seven tertiary care centers. After IRB approval, retrospective analysis of prospectively maintained stroke/endovascular databases was performed. RESULTS: A total of seven subjects were identified. The average age was 33.2 years (range 25-38 years) and the average initial National Institutes of Health Stroke Scale (NIHSS) score at presentation was 15 (range 9-28). Three patients received IV tissue plasminogen activator. Techniques of EVT included stent retriever thrombectomy, stent retriever-assisted continuous aspiration, direct contact aspiration, and multimodal techniques including a rescue balloon mounted coronary stent placement. While one patient was noted to have petechial hemorrhage, no individuals developed parenchymal hematoma. Mean discharge NIHSS score was 1.7 (range 0-5). CONCLUSION: EVT is a safe and effective treatment for acute stroke secondary to LVO in this series of pregnant patients. While EVT for acute stroke is standard of care in select patient populations, our study suggests that treatment should be considered in the gravid population.