Trial of Endovascular Thrombectomy for Large Ischemic Strokes.

BACKGROUND: Trials of the efficacy and safety of endovascular thrombectomy in patients with large ischemic strokes have been carried out in limited populations. METHODS: We performed a prospective, randomized, open-label, adaptive, international trial involving patients with stroke due to occlusion of the internal carotid artery or the first segment of the middle cerebral artery to assess endovascular thrombectomy within 24 hours after onset. Patients had a large ischemic-core volume, defined as an Alberta Stroke Program Early Computed Tomography Score of 3 to 5 (range, 0 to 10, with lower scores indicating larger infarction) or a core volume of at least 50 ml on computed tomography perfusion or diffusion-weighted magnetic resonance imaging. Patients were assigned in a 1:1 ratio to endovascular thrombectomy plus medical care or to medical care alone. The primary outcome was the modified Rankin scale score at 90 days (range, 0 to 6, with higher scores indicating greater disability). Functional independence was a secondary outcome. RESULTS: The trial was stopped early for efficacy; 178 patients had been assigned to the thrombectomy group and 174 to the medical-care group. The generalized odds ratio for a shift in the distribution of modified Rankin scale scores toward better outcomes in favor of thrombectomy was 1.51 (95% confidence interval [CI], 1.20 to 1.89; P<0.001). A total of 20% of the patients in the thrombectomy group and 7% in the medical-care group had functional independence (relative risk, 2.97; 95% CI, 1.60 to 5.51). Mortality was similar in the two groups. In the thrombectomy group, arterial access-site complications occurred in 5 patients, dissection in 10, cerebral-vessel perforation in 7, and transient vasospasm in 11. Symptomatic intracranial hemorrhage occurred in 1 patient in the thrombectomy group and in 2 in the medical-care group. CONCLUSIONS: Among patients with large ischemic strokes, endovascular thrombectomy resulted in better functional outcomes than medical care but was associated with vascular complications. Cerebral hemorrhages were infrequent in both groups. (Funded by Stryker Neurovascular; SELECT2 ClinicalTrials.gov number, NCT03876457.).

Endovascular thrombectomy plus medical care versus medical care alone for large ischaemic stroke: 1-year outcomes of the SELECT2 trial.

BACKGROUND: Multiple randomised trials have shown efficacy and safety of endovascular thrombectomy in patients with large ischaemic stroke. The aim of this study was to evaluate long-term (ie, at 1 year) evidence of benefit of thrombectomy for these patients. METHODS: SELECT2 was a phase 3, open-label, international, randomised controlled trial with blinded endpoint assessment, conducted at 31 hospitals in the USA, Canada, Spain, Switzerland, Australia, and New Zealand. Patients aged 18-85 years with ischaemic stroke due to proximal occlusion of the internal carotid artery or of the first segment of the middle cerebral artery, showing large ischaemic core on non-contrast CT (Alberta Stroke Program Early Computed Tomographic Score of 3-5 [range 0-10, with lower values indicating larger infarctions]) or measuring 50 mL or more on CT perfusion and MRI, were randomly assigned, within 24 h of ischaemic stroke onset, to thrombectomy plus medical care or to medical care alone. The primary outcome for this analysis was the ordinal modified Rankin Scale (range 0-6, with higher scores indicating greater disability) at 1-year follow-up in an intention-to-treat population. The trial is registered at ClinicalTrials.gov (NCT03876457) and is completed. FINDINGS: The trial was terminated early for efficacy at the 90-day follow-up after 352 patients had been randomly assigned (178 to thrombectomy and 174 to medical care only) between Oct 11, 2019, and Sept 9, 2022. Thrombectomy significantly improved the 1-year modified Rankin Scale score distribution versus medical care alone (Wilcoxon-Mann-Whitney probability of superiority 0·59 [95% CI 0·53-0·64]; p=0·0019; generalised odds ratio 1·43 [95% CI 1·14-1·78]). At the 1-year follow-up, 77 (45%) of 170 patients receiving thrombectomy had died, compared with 83 (52%) of 159 patients receiving medical care only (1-year mortality relative risk 0·89 [95% CI 0·71-1·11]). INTERPRETATION: In patients with ischaemic stroke due to a proximal occlusion and large core, thrombectomy plus medical care provided a significant functional outcome benefit compared with medical care alone at 1-year follow-up. FUNDING: Stryker Neurovascular.

Cervical Dissection in Patients With Tandem Lesions Is Associated With Distal Embolism and Lower Recanalization Success.

BACKGROUND: Tandem lesions consist of cervical internal carotid artery (ICA) stenosis or occlusion, most commonly of atherosclerosis or dissection etiology, plus a large vessel occlusion. In this study, we compare outcomes in patients with atherosclerosis versus dissection of the cervical ICA. METHODS: This multicenter retrospective cohort study includes data from tandem lesion patients who underwent endovascular treatment from 2015 to 2020. Atherosclerosis was defined as ICA stenosis/occlusion associated with a calcified lesion and dissection by the presence of a tapered or flame-shaped lesion and intramural hematoma. Primary outcome: 90-day functional independence (modified Rankin Scale score, 0-2); secondary outcomes: 90-day favorable shift in the modified Rankin Scale score, modified Thrombolysis in Cerebral Infarction score 2b-3, modified Thrombolysis in Cerebral Infarction score 2c-3, symptomatic intracranial hemorrhage, parenchymal hematoma type 2, petechial hemorrhage, distal embolization, early neurological improvement, and mortality. Analysis was performed with matching by inverse probability of treatment weighting. RESULTS: We included 526 patients (68 [59-76] years; 31% females); 11.2% presented dissection and 88.8%, atherosclerosis. Patients with dissection were younger, had lower rates of hypertension, hyperlipidemia, diabetes, and smoking history. They also exhibited higher rates of ICA occlusion, multiple stents (>1), and lower rates of carotid self-expanding stents. After matching and adjusting for covariates, there were no differences in 90-day functional independence. The rate of successful recanalization was significantly lower in the dissection group (adjusted odds ratio, 0.38 [95% CI, 0.16-0.91]; P=0.031), which also had significantly higher rates of distal emboli (adjusted odds ratio, 2.53 [95% CI, 1.15-5.55]; P=0.021). There were no differences in other outcomes. Acute ICA stenting seemed to increase the effect of atherosclerosis in successful recanalization. CONCLUSIONS: This study reveals that among patients with acute stroke with tandem lesions, cervical ICA dissection is associated with higher rates of distal embolism and lower rates of successful recanalization than atherosclerotic lesions. Using techniques to minimize the risk of distal embolism may mitigate this contrast. Further prospective randomized trials are warranted to fully understand these associations.

Mediation of Successful Reperfusion Effect through Infarct Growth and Cerebral Edema: A Pooled, Patient-Level Analysis of EXTEND-IA Trials and SELECT Prospective Cohort.

OBJECTIVE: Reperfusion therapy is highly beneficial for ischemic stroke. Reduction in both infarct growth and edema are plausible mediators of clinical benefit with reperfusion. We aimed to quantify these mediators and their interrelationship. METHODS: In a pooled, patient-level analysis of the EXTEND-IA trials and SELECT study, we used a mediation analysis framework to quantify infarct growth and cerebral edema (midline shift) mediation effect on successful reperfusion (modified Treatment in Cerebral Ischemia ≥ 2b) association with functional outcome (modified Rankin Scale distribution). Furthermore, we evaluated an additional pathway to the original hypothesis, where infarct growth mediated successful reperfusion effect on midline shift. RESULTS: A total 542 of 665 (81.5%) eligible patients achieved successful reperfusion. Baseline clinical and imaging characteristics were largely similar between those achieving successful versus unsuccessful reperfusion. Median infarct growth was 12.3ml (interquartile range [IQR] = 1.8-48.4), and median midline shift was 0mm (IQR = 0-2.2). Of 249 (37%) demonstrating a midline shift of ≥1mm, median shift was 2.75mm (IQR = 1.89-4.21). Successful reperfusion was associated with reductions in both predefined mediators, infarct growth (ß = -1.19, 95% confidence interval [CI] = -1.51 to -0.88, p < 0.001) and midline shift (adjusted odds ratio = 0.36, 95% CI = 0.23-0.57, p < 0.001). Successful reperfusion association with improved functional outcome (adjusted common odds ratio [acOR] = 2.68, 95% CI = 1.86-3.88, p < 0.001) became insignificant (acOR = 1.39, 95% CI = 0.95-2.04, p = 0.094) when infarct growth and midline shift were added to the regression model. Infarct growth and midline shift explained 45% and 34% of successful reperfusion effect, respectively. Analysis considering an alternative hypothesis demonstrated consistent results. INTERPRETATION: In this mediation analysis from a pooled, patient-level cohort, a significant proportion (~80%) of successful reperfusion effect on functional outcome was mediated through reduction in infarct growth and cerebral edema. Further studies are required to confirm our findings, detect additional mediators to explain successful reperfusion residual effect, and identify novel therapeutic targets to further enhance reperfusion benefits. ANN NEUROL 2023;93:793-804.

Incidence of Symptomatic Venous Thromboembolisms in Stroke Patients.

Venous thromboembolism (VTE) is a common but preventable complication observed in critically ill patients. Deep vein thrombosis (DVT) is the most common type of VTE, with clinical significance based on location and symptoms. There is an increased incidence of DVT and pulmonary embolism (PE) in ischemic stroke patients using unfractionated heparin (UFH) for VTE prophylaxis compared with those using enoxaparin. However, UFH is still used in some patients due to its perceived safety, despite conflicting literature suggesting that enoxaparin may have a protective effect. The current study aimed to determine the incidence of VTEs in patients with acute ischemic strokes on UFH versus enoxaparin for VTE prophylaxis, subclassifying the VTEs depending on their location and symptoms. It also aimed to examine the safety profile of both drugs. A total of 909 patients admitted to the Neuro-ICU with the diagnosis of acute ischemic stroke were identified, and 634 patients were enrolled in the study-170 in the enoxaparin group and 464 in the UFH group-after applying the exclusion criteria. Nineteen patients in the UFH group (4.1%) and 3 patients in the enoxaparin group (1.8%) had a VTE. The incidence of DVT in the UFH group was 12 (2.6%), all of which were symptomatic, compared with 3 (1.8%) in the enoxaparin group, wherein one case was symptomatic. Nine patients (1.9%) in the UFH group developed a PE during the study period, and all of them were symptomatic. No patients in the enoxaparin group developed PE. No statistically significant difference was found between both groups. However, 18 patients in the UFH group (3.9%) experienced intracranial hemorrhage compared with none in the enoxaparin group, and this difference was statistically significant. Enoxaparin was found to be as effective as and potentially safer than UFH when used for VTE prophylaxis in stroke patients.

A Systematic Review and Meta-Analysis of Drug Eluting Stents for Safety and Efficacy in Intracranial Atherosclerotic Disease.

BACKGROUND: Advancements in arterial stenting technology have challenged prior notions favoring medical management for intracranial atherosclerotic disease (ICAD). Where previous conclusions were drawn from bare metal stent (BMS) technology, recent studies suggest drug-eluting stents (DES) are favorable due to their anti-proliferative effect, which reduces vascular remodeling. METHODS: We conducted a systematic review and meta-analysis of the literature prior to August 2023 reviewing all reports of ICAD treated with DES. Our target outcomes were incidence of any stroke, transient ischemic attack (TIA), or death within 30 days (postprocedural complications), ischemic stroke in the territory of the qualifying artery beyond 30 days (long-term complications), radiographically detected in-stent restenosis rate (ISR), and symptomatic ISR during follow-up. A subgroup analysis further stratified preprocedural mean stenosis above and below 70% into severe and moderate cohorts, respectively. RESULTS: PubMed, Web of Science, Cochrane and EMBASE query identified 527 candidate articles, from which 14 studies met inclusion criteria for a total of 607 patients and 640 ICAD lesions. Incidence of postprocedural complications was 7.3% (95% CI 3.9-11.7%) with subgroup analysis demonstrating significantly higher incidence in the severely stenotic group [9.0% (95% CI 4.7-14.5%)] than the moderately stenotic group [3.0% (95% CI 0.7-6.8%)]. Long-term complications were 1.2% (95% CI 0.4-2.3%). Radiographic ISR was 3.5% (95% CI 1.4-6.3%) and symptomatic ISR was 0.3% (95% CI 0.0-1.5%). CONCLUSIONS: Our systematic review and meta-analysis suggest that DES can effectively reduce the risk of ISR and may be a viable treatment modality to reduce long-term complications in refractory ICAD patients.

Endovascular Thrombectomy for Large Ischemic Stroke Across Ischemic Injury and Penumbra Profiles.

Importance: Whether endovascular thrombectomy (EVT) efficacy for patients with acute ischemic stroke and large cores varies depending on the extent of ischemic injury is uncertain. Objective: To describe the relationship between imaging estimates of irreversibly injured brain (core) and at-risk regions (mismatch) and clinical outcomes and EVT treatment effect. Design, Setting, and Participants: An exploratory analysis of the SELECT2 trial, which randomized 352 adults (18-85 years) with acute ischemic stroke due to occlusion of the internal carotid or middle cerebral artery (M1 segment) and large ischemic core to EVT vs medical management (MM), across 31 global centers between October 2019 and September 2022. Intervention: EVT vs MM. Main Outcomes and Measures: Primary outcome was functional outcome-90-day mRS score (0, no symptoms, to 6, death) assessed by adjusted generalized OR (aGenOR; values >1 represent more favorable outcomes). Benefit of EVT vs MM was assessed across levels of ischemic injury defined by noncontrast CT using ASPECTS score and by the volume of brain with severely reduced blood flow on CT perfusion or restricted diffusion on MRI. Results: Among 352 patients randomized, 336 were analyzed (median age, 67 years; 139 [41.4%] female); of these, 168 (50%) were randomized to EVT, and 2 additional crossover MM patients received EVT. In an ordinal analysis of mRS at 90 days, EVT improved functional outcomes compared with MM within ASPECTS categories of 3 (aGenOR, 1.71 [95% CI, 1.04-2.81]), 4 (aGenOR, 2.01 [95% CI, 1.19-3.40]), and 5 (aGenOR, 1.85 [95% CI, 1.22-2.79]). Across strata for CT perfusion/MRI ischemic core volumes, aGenOR for EVT vs MM was 1.63 (95% CI, 1.23-2.16) for volumes ≥70 mL, 1.41 (95% CI, 0.99-2.02) for ≥100 mL, and 1.47 (95% CI, 0.84-2.56) for ≥150 mL. In the EVT group, outcomes worsened as ASPECTS decreased (aGenOR, 0.91 [95% CI, 0.82-1.00] per 1-point decrease) and as CT perfusion/MRI ischemic core volume increased (aGenOR, 0.92 [95% CI, 0.89-0.95] per 10-mL increase). No heterogeneity of EVT treatment effect was observed with or without mismatch, although few patients without mismatch were enrolled. Conclusion and Relevance: In this exploratory analysis of a randomized clinical trial of patients with extensive ischemic stroke, EVT improved clinical outcomes across a wide spectrum of infarct volumes, although enrollment of patients with minimal penumbra volume was low. In EVT-treated patients, clinical outcomes worsened as presenting ischemic injury estimates increased. Trial Registration: ClinicalTrials.gov Identifier: NCT03876457.

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.

Endovascular Thrombectomy Versus Medical Management in Isolated M2 Occlusions: Pooled Patient-Level Analysis from the EXTEND-IA Trials, INSPIRE, and SELECT Studies.

OBJECTIVE: The objective of this study was to evaluate functional and safety outcomes of endovascular thrombectomy (EVT) versus medical management (MM) in patients with M2 occlusion and examine their association with perfusion imaging mismatch and stroke severity. METHODS: In a pooled, patient-level analysis of 3 randomized controlled trials (EXTEND-IA, EXTEND-and IA-TNK parts 1 and 2) and 2 prospective nonrandomized studies (INSPIRE and SELECT), we evaluated EVT association with 90-day functional independence (modified Rankin Scale [mRS] = 0-2) in isolated M2 occlusions as compared to medical management overall and in subgroups by mismatch profile status and stroke severity. RESULTS: We included 517 patients (EVT = 195 and MM = 322), baseline median (interquartile range [IQR]) National Institutes of Health Stroke Scale (NIHSS) was 13 (8-19) in EVT versus 10 (6-15) in MM, p < 0.001. Pretreatment ischemic core did not differ (EVT = 10 [0-24] ml vs MM = 9 [3-21] ml, p = 0.59). Compared to MM, EVT was more frequently associated with functional independence (68.3 vs 61.6%, adjusted odds ratio [aOR] = 2.42, 95% confidence interval [CI] = 1.25-4.67, p = 0.008, inverse probability of treatment weights [IPTW]-OR = 1.75, 95% CI = 1.00-3.75, p = 0.05) with a shift toward better mRS outcomes (adjusted cOR = 2.02, 95% CI:1.23-3.29, p = 0.005), and lower mortality (5 vs 10%, aOR = 0.32, 95% CI = 0.12-0.87, p = 0.025). EVT was associated with higher functional independence in patients with a perfusion mismatch profile (EVT = 70.7% vs MM = 61.3%, aOR = 2.29, 95% CI = 1.09-4.79, p = 0.029, IPTW-OR = 2.02, 1.08-3.78, p = 0.029), whereas no difference was found in those without mismatch (EVT = 43.8% vs MM = 62.7%, p = 0.17, IPTW-OR: 0.71, 95% CI = 0.18-2.78, p = 0.62). Functional independence was more frequent with EVT in patients with moderate or severe strokes, as defined by baseline NIHSS above any thresholds from 6 to 10, whereas there was no difference between groups with milder strokes below these thresholds. INTERPRETATION: In patients with M2 occlusion, EVT was associated with improved clinical outcomes when compared to MM. This association was primarily observed in patients with a mismatch profile and those with higher stroke severity. ANN NEUROL 2022;91:629-639.

Thrombectomy versus Medical Management in Mild Strokes due to Large Vessel Occlusion: Exploratory Analysis from the EXTEND-IA Trials and a Pooled International Cohort.

OBJECTIVE: This study was undertaken to evaluate functional and safety outcomes for endovascular thrombectomy (EVT) versus medical management (MM) in patients with large vessel occlusion (LVO) and mild neurological deficits, stratified by perfusion imaging mismatch. METHODS: The pooled cohort consisted of patients with National Institutes of Health Stroke Scale (NIHSS) < 6 and internal carotid artery (ICA), M1, or M2 occlusions from the Extending the Time for Thrombolysis in Emergecy Neurological Deficits - Intra-Arterial (EXTEND-IA) Trial,  Tenecteplase vs Alteplase before Endovascular Thrombectomy in Ischemic Stroke (EXTEND-IA TNK) trials Part I/II and prospective data from 15 EVT centers from October 2010 to April 2020. RAPID software estimated ischemic core and mismatch. Patients receiving primary EVT (EVTpri ) were compared to those who received primary MM (MMpri ), including those who deteriorated and received rescue EVT, in overall and propensity score (PS)-matched cohorts. Patients were stratified by target mismatch (mismatch ratio ≥ 1.8 and mismatch volume ≥ 15ml). Primary outcome was functional independence (90-day modified Rankin Scale = 0-2). Secondary outcomes included safety (symptomatic intracerebral hemorrhage [sICH], neurological worsening, and mortality). RESULTS: Of 540 patients, 286 (53%) received EVTpri and demonstrated larger critically hypoperfused tissue (Tmax > 6 seconds) volumes (median [IQR]: 64 [26-96] ml vs MMpri : 40 [14-76] ml, p < 0.001) and higher presentation NIHSS (median [IQR]: 4 [2-5] vs MMpri : 3 [2-4], p < 0.001). Functional independence was similar (EVTpri : 77.4% vs MMpri : 75.6%, adjusted odds ratio [aOR] = 1.29, 95% confidence interval [CI] = 0.82-2.03, p = 0.27). EVT had worse safety regarding sICH (EVTpri : 16.3% vs MMpri : 1.3%, p < 0.001) and neurological worsening (EVTpri : 19.6% vs MMpri : 6.7%, p < 0.001). In 414 subjects (76.7%) with target mismatch, EVT was associated with improved functional independence (EVTpri : 77.4% vs MMpri : 72.7%, aOR = 1.68, 95% CI = 1.01-2.81, p = 0.048), whereas there was a trend toward less favorable outcomes with primary EVT (EVTpri : 77.4% vs MMpri : 83.3%, aOR = 0.39, 95% CI = 0.12-1.34, p = 0.13) without target mismatch (pinteraction  = 0.06). Similar findings were observed in a propensity score-matched subpopulation. INTERPRETATION: Overall, EVT was not associated with improved clinical outcomes in mild strokes due to LVO, and sICH was increased. However, in patients with target mismatch profile, EVT was associated with increased functional independence. Perfusion imaging may be helpful to select mild stroke patients for EVT. ANN NEUROL 2022;92:364-378.

Dual-Stent retriever thrombectomy for extensive dural sinus thrombosis.

INTRODUCTION: First line treatment for cerebral venous thrombosis (CVT) is systemic anticoagulation. In cases with symptoms of elevated ICP, endovascular thrombectomy (EVT) is pursued. We describe two cases in which dual stent-retrievers were used for EVT. OBJECTIVES: The use of dual stent-retrievers has been described in arterial stroke when clot is present in the M1 artery and both M2 branches as a rescue therapy after 1 stent-retriever failed to remove the clot. We applied this same thinking to our EVT patients. METHODS: A 17-year-old female with imaging demonstrating occlusion of the superior sagittal sinus (SSS), dominant right transverse sinus (TS), right sigmoid sinus (SS), and upper right internal jugular vein (IJV). A 20-year-old female with a magnetic resonance venography (MRV) noting CVT in the dominant lateral left TS, SS, and upper left IJV. RESULTS: Both were taken for EVT due to severity of symptoms. Two 6 × 40 mm stent-retrievers were deployed into the CVT and then remove with continuous aspiration with significant recanalization. CONCLUSIONS: The average diameter of the dural sinuses is 8 mm compared to the average size of the middle cerebral artery 3-4 mm. The largest available SR in the United States is 6 mm, and the largest outer diameter of available aspiration catheters is 2-3 mm. Due to the larger size of the dural sinuses, using two SRs can result in more efficient recanalization and less radiation.

Low dose intravenous cangrelor versus glycoprotein IIb/IIIa inhibitors in endovascular treatment of tandem lesions.

OBJECTIVES: Intravenous (IV) periprocedural antiplatelet therapy (APT) for patients undergoing acute carotid stenting during mechanical thrombectomy (MT) is not fully investigated. We aimed to compare the safety profile of IV low dose cangrelor versus IV glycoprotein IIb/IIIa (GP-IIb/IIIa) inhibitors in patients with acute tandem lesions (TLs). MATERIALS AND METHODS: We retrospectively identified all cases of periprocedural administration of IV cangrelor or GP-IIb/IIIa inhibitors during acute TLs intervention from a multicenter collaboration. Patients were divided in two groups according to the IV APT regimen at the time of MT procedure: 1) cangrelor and 2) GP-IIb/IIIa inhibitors (tirofiban and eptifibatide). Safety outcomes included rates of symptomatic intracranial hemorrhage (sICH), parenchymal hematoma type 1 and 2 (PH1-PH2), and hemorrhagic infarction type 1 and 2 (HI1-HI2). RESULTS: Sixty-three patients received IV APT during MT, 30 were in the cangrelor group, and 33 were in the GP-IIb/IIIa inhibitors group. There were no significant differences in the rates of sICH (3.3% vs. 12.1%, aOR=0.21, 95%CI 0.02-2.18, p=0.229), HI1-HI2 (21.4% vs 42.4%, aOR=0.21, 95%CI 0.02-2.18, p=0.229), and PH1-PH2 (17.9% vs. 12.1%, aOR=1.63, 95%CI 0.29-9.83, p=0.577) between both treatment groups. However, there was a trend toward reduced hemorrhage rates with cangrelor. Cangrelor was associated with increased odds of complete reperfusion (aOR=5.86; 95%CI 1.57-26.62;p=0.013). CONCLUSIONS: In this retrospective non-randomized cohort study, our findings suggest that low dose cangrelor has similar safety and increased rate of complete reperfusion compared to IV GP-IIb/IIIa inhibitors. Further prospective studies are warranted to confirm this association.

Photo-Oxidizing Ruthenium(II) Complexes with Enhanced Visible-Light Absorption and G-quadruplex DNA Binding Abilities.

Photosensitizers that gather high photo-oxidizing power and strong visible-light absorption are of great interest in the development of new photo-chemotherapeutics. Indeed, such compounds constitute attractive candidates for the design of type I photosensitizers that are not dependent on the presence of oxygen. In this paper, we report on the synthesis and studies of new ruthenium(II) complexes that display strong visible-light absorption and can oxidize guanine residues under visible-light irradiation, as evidenced by nanosecond transient absorption spectroscopy. The reported compounds also tightly bind to G-quadruplex DNA structures from the human telomeric sequence (TTAGGG repeat). The kinetic and thermodynamic parameters of the interaction of these Ru(II) complexes with G-quadruplex and duplex DNA were studied thanks to luminescence titrations and bio-layer interferometry measurements, which revealed higher affinities towards the non-canonical G-quadruplex architecture. Docking experiments and non-covalent ionic analysis allowed us to gain information on the mode and the strength of the interaction of the compounds towards G-quadruplex and duplex DNA. The different studies emphasize the substantial influence of the position and the number of non-chelating nitrogen atoms on the interaction with both types of DNA secondary structures.

Group Contribution and Machine Learning Approaches to Predict Abraham Solute Parameters, Solvation Free Energy, and Solvation Enthalpy.

We present a group contribution method (SoluteGC) and a machine learning model (SoluteML) to predict the Abraham solute parameters, as well as a machine learning model (DirectML) to predict solvation free energy and enthalpy at 298 K. The proposed group contribution method uses atom-centered functional groups with corrections for ring and polycyclic strain while the machine learning models adopt a directed message passing neural network. The solute parameters predicted from SoluteGC and SoluteML are used to calculate solvation energy and enthalpy via linear free energy relationships. Extensive data sets containing 8366 solute parameters, 20,253 solvation free energies, and 6322 solvation enthalpies are compiled in this work to train the models. The three models are each evaluated on the same test sets using both random and substructure-based solute splits for solvation energy and enthalpy predictions. The results show that the DirectML model is superior to the SoluteML and SoluteGC models for both predictions and can provide accuracy comparable to that of advanced quantum chemistry methods. Yet, even though the DirectML model performs better in general, all three models are useful for various purposes. Uncertain predicted values can be identified by comparing the three models, and when the 3 models are combined together, they can provide even more accurate predictions than any one of them individually. Finally, we present our compiled solute parameter, solvation energy, and solvation enthalpy databases (SoluteDB, dGsolvDBx, dHsolvDB) and provide public access to our final prediction models through a simple web-based tool, software packages, and source code.

Takotsubo cardiomyopathy in the setting of a myasthenic crisis.

BACKGROUND: Myasthenic crisis is characterized by severe weakness in bulbar and respiratory muscles leading to respiratory failure and can be a natural result of myasthenia gravis or precipitate due to infections, surgeries, and pregnancy. It has been shown that stressful emotional events can lead to stress, or takotsubo cardiomyopathy. Takotsubo cardiomyopathy is characterized by transient reversible left ventricular dysfunction in the absence of obstructive artery disease with hypo- or akinesis of the apex with hypercontractility of the base. METHODS: Case report and review of literature. RESULTS: We report a 77-year old man with myasthenia gravis that was admitted to the neurological intensive care unit due to a myasthenic crisis. During the course of his treatment with plasma exchange, he developed hypotension with a reduced cardiac ejection fraction found on transthoracic electrocardiography. Repeat echocardiography 2 and 8 days later showed a normal ejection fraction and resolved cardiac function. CONCLUSION: While takotsubo cardiomyopathy rarely presents concurrently with a myasthenic crisis, its consideration is warranted in the face of cardiovascular decompensation. Given that several cardiac complications are known to be associated with myasthenic crisis, cardiac monitoring is advised. Nine reports describe takotsubo cardiomyopathy occurring concurrently with a myasthenic crisis; however, only one report demonstrates this association in the absence of concomitant comorbidities or significant emotional distress.

Higher-Quality Data Collection Is Critical to Establish the Safety and Efficacy of Pediatric Mechanical Thrombectomy.

BACKGROUND AND PURPOSE: Because children often have lifelong morbidity after stroke, there is considerable enthusiasm to pursue mechanical thrombectomy in childhood stroke based on literature reports. However, current published data may reflect inconsistent reporting and publication bias, which limit the ability to assess safety and efficacy of mechanical thrombectomy in childhood stroke. METHODS: This retrospective cohort study compared reporting quality and clinical outcomes for mechanical thrombectomy between a trial-derived cohort of 42 children treated with mechanical thrombectomy for acute stroke at study sites and 133 patients reported in the literature. National Institutes of Health Stroke Scale at baseline, 24 hours after mechanical thrombectomy, and at discharge were compared between study site patients and literature patients. Odds ratios (ORs) were used to compare reporting frequencies. Proportional odds logistic regression was used to compare outcomes. RESULTS: Premechanical thrombectomy National Institutes of Health Stroke Scale was available in 93% of study patients compared with 74% of patients in the literature (OR, 4.42 [95% CI, 1.47-19.89]). Postmechanical thrombectomy National Institutes of Health Stroke Scale was available in 69% of study patients compared with 29% of literature cases at 24 hours (OR, 5.48 [95% CI, 2.62-12.06]), and 64% of study patients compared with 32% of cases at discharge (OR, 3.85 [95% CI, 1.87-8.19]). For study sites, median scores were 12 at baseline, 9 at 24 hours, and 5 at discharge. Median scores in case reports were 15 at baseline, 4 at 24 hours, and 3 at discharge. ORs for differences in outcomes between groups were 5.97 (95% CI, 2.28-15.59) at 24 hours and 3.68 (95% CI, 1.45-9.34) at discharge. CONCLUSIONS: Study site patients had higher rates of National Institutes of Health Stroke Scale reporting and worse short-term outcomes compared with literature reports. Rigorous data collection is needed before treatment guidelines for pediatric mechanical thrombectomy can be developed.

Early Infarct Growth Rate Correlation With Endovascular Thrombectomy Clinical Outcomes: Analysis From the SELECT Study.

BACKGROUND AND PURPOSE: Time elapsed from last-known well (LKW) and baseline imaging results are influential on endovascular thrombectomy (EVT) outcomes. METHODS: In a prospective multicenter cohort study of imaging selection for endovascular thrombectomy (SELECT [Optimizing Patient's Selection for Endovascular Treatment in Acute Ischemic Stroke], the early infarct growth rate (EIGR) was defined as ischemic core volume on perfusion imaging (relative cerebral blood flow<30%) divided by the time from LKW to imaging. The optimal EIGR cutoff was identified by maximizing the sum of the sensitivity and specificity to correlate best with favorable outcome and to improve its the predictability. Patients were stratified into slow progressors if EIGR2. The primary outcome was 90-day functional independence (modified Rankin Scale score =0-2). RESULTS: Of 445 consented, 361 (285 EVT, 76 medical management only) patients met the study inclusion criteria. The optimal EIGR was <10 mL/h; 200 EVT patients were slow and 85 fast progressors. Fast progressors had a higher median National Institutes of Health Stroke Scale (19 versus 15, P<0.001), shorter time from LKW to groin puncture (180 versus 266 minutes, P<0.001). Slow progressors had better collaterals on computed tomography perfusion: hypoperfusion intensity ratio (adjusted odds ratio [aOR]: 5.11 [2.43-10.76], P<0.001) and computed tomography angiography: collaterals-score (aOR: 4.43 [1.83-10.73], P=0.001). EIGR independently correlated with functional independence after EVT, adjusting for age, National Institutes of Health Stroke Scale, time LKW to groin puncture, reperfusion (modified Thrombolysis in Cerebral Infarction score of ≥2b), IV-tPA (intravenous tissue-type plasminogen activator), and transfer status (aOR: 0.78 [0.65-0.94], P=0.01). Slow progressors had higher functional independence rates (121 [61%] versus 30 [35%], P<0.001) and had 3.5 times the likelihood of achieving modified Rankin Scale score =0-2 with EVT (aOR=2.94 [95% CI, 1.53-5.61], P=0.001) as compared to fast progressors, who had substantially worse clinical outcomes both in early and late time window. The odds of good outcome decreased by 14% for each 5 mL/h increase in EIGR (aOR, 0.87 [0.80-0.94], P<0.001) and declined more rapidly in fast progressors. CONCLUSIONS: The EIGR strongly correlates with both collateral status and clinical outcomes after EVT. Fast progressors demonstrated worse outcomes when receiving EVT beyond 6 hours of stroke onset as compared to those who received EVT within 6 hours. Registration: URL: https://clinicaltrials.gov. Unique identifier: NCT02446587.

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 .).

Optimizing Patient Selection for Endovascular Treatment in Acute Ischemic Stroke (SELECT): A Prospective, Multicenter Cohort Study of Imaging Selection.

OBJECTIVE: The primary imaging modalities used to select patients for endovascular thrombectomy (EVT) are noncontrast computed tomography (CT) and CT perfusion (CTP). However, their relative utility is uncertain. We prospectively assessed CT and CTP concordance/discordance and correlated the imaging profiles on both with EVT treatment decisions and clinical outcomes. METHODS: A phase 2, multicenter, prospective cohort study of large-vessel occlusions presented up to 24 hours from last known well was conducted. Patients received a unified prespecified imaging evaluation (CT, CT angiography, and CTP with Rapid Processing of Perfusion and Diffusion software mismatch determination). The treatment decision, EVT versus medical management, was nonrandomized and at the treating physicians' discretion. An independent, blinded, neuroimaging core laboratory adjudicated favorable profiles based on predefined criteria (CT:Alberta Stroke Program Early CT Score ≥ 6, CTP:regional cerebral blood flow (<30%) < 70ml with mismatch ratio ≥ 1.2 and mismatch volume ≥ 10ml). RESULTS: Of 4,722 patients screened from January 2016 to February 2018, 361 patients were included. Two hundred eighty-five (79%) received EVT, of whom 87.0% had favorable CTs, 91% favorable CTPs, 81% both favorable profiles, 16% discordant, and 3% both unfavorable. Favorable profiles on the 2 modalities correlated similarly with 90-day functional independence rates (favorable CT = 56% vs favorable CTP = 57%, adjusted odds ratio [aOR] = 1.91, 95% confidence interval [CI] = 0.40-9.01, p = 0.41). Having a favorable profile on both modalities significantly increased the odds of receiving thrombectomy as compared to discordant profiles (aOR = 3.97, 95% CI = 1.97-8.01, p < 0.001). Fifty-eight percent of the patients with favorable profiles on both modalities achieved functional independence as compared to 38% in discordant profiles and 0% when both were unfavorable (p < 0.001 for trend). In favorable CT/unfavorable CTP profiles, EVT was associated with high symptomatic intracranial hemorrhage (sICH) (24%) and mortality (53%) rates. INTERPRETATION: Patients with favorable imaging profiles on both modalities had higher odds of receiving EVT and high functional independence rates. Patients with discordant profiles achieved reasonable functional independence rates, but those with an unfavorable CTP had higher adverse outcomes. Ann Neurol 2020;87:419-433.

Properties of the tert-butyl halide solvolysis transition states.

We have obtained properties (or descriptors) of the transition states in the solvolysis of tert-butyl chloride, bromide and iodide. We show that all three transition states, in both protic and in aprotic solvents, are highly dipolar and are strong hydrogen bond acids and strong hydrogen bond bases, except for the tert-butyl iodide transition state in aprotic solvents, which has a rather low hydrogen bond acidity. Thus, the transition states are stabilized by solvents that are hydrogen bond bases (nucleophiles) and are hydrogen bond acids (electrophiles). We show also that the partition of the transition states between water and solvents is aided by both nucleophilic and electrophilic solvents and conclude that the rate of solvolysis of the three halides is increased by both nucleophilic and electrophilic solvents.