Aspiration Versus Stent Retriever Thrombectomy for Posterior Circulation Stroke

BACKGROUND AND PURPOSE: Whereas a clear benefit of endovascular treatment for anterior circulation stroke has been established, randomized trials assessing the posterior circulation have failed to show efficacy. Previous studies in anterior circulation stroke suggest that advanced thrombectomy devices were of great importance in achieving clinical benefit. Little is known about the effect of thrombectomy techniques on outcomes in posterior circulation stroke. In this study, we compare first-line strategy of direct aspiration to stent retriever thrombectomy for posterior circulation stroke. METHODS: We analyzed data of patients with a posterior circulation stroke who were included in the Multicentre Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry between March 2014 and December 2018, a prospective, nationwide study, in which data were collected from consecutive patients who underwent endovascular treatment for ischemic stroke in the Netherlands. We compared patients who underwent first-line aspiration versus stent retriever thrombectomy. Primary outcome was functional outcome according to the modified Rankin Scale. Secondary outcomes were reperfusion grade, complication rate, and procedure duration. Associations between thrombectomy technique and outcome measures were estimated with multivariable ordinal logistic regression analyses. RESULTS: Overall, 71 of 205 patients (35%) were treated with aspiration, and 134 (65%) with stent retriever thrombectomy. Patients in the aspiration group had a lower pc-ASPECTS on baseline computed tomography, and general anesthesia was more often applied in this group. First-line aspiration was associated with better functional outcome compared with stent retriever thrombectomy (adjusted common odds ratio for a 1-point improvement on the modified Rankin Scale 1.94 [95% CI, 1.03-3.65]). Successful reperfusion (extended Thrombolysis in Cerebral Infarction ≥2B) was achieved more often with aspiration (87% versus 73%, P=0.03). Symptomatic hemorrhage rates were comparable (3% versus 4%). Procedure times were shorter in the aspiration group (49 versus 69 minutes P<0.001). CONCLUSIONS: In this retrospective nonrandomized cohort study, our findings suggest that first-line aspiration is associated with a shorter procedure time, better reperfusion, and better clinical outcome than stent retriever thrombectomy in patients with ischemic stroke based on large vessel occlusion in the posterior circulation

Association of thrombus density and endovascular treatment outcomes in patients with acute ischemic stroke due to M1 occlusions

PURPOSE: We aimed to study the association of non-contrast CT (NCCT) thrombus density with procedural and clinical outcomes in patients with acute ischemic stroke who underwent endovascular treatment (EVT). Since thrombus density is associated with thrombus location, we focused on M1 occlusions only.METHODS: Patients with available thin-slice (&lt; 2.5 mm) NCCT were included from a nationwide registry. Regression models were used to assess the relation between thrombus density (per Hounsfield unit [HU]) and the following outcomes. For reperfusion grade, adjusted common odds ratios (acOR) indicated a 1-step shift towards improved outcome per HU increase in thrombus density. For the binary outcomes of first-pass reperfusion (first-pass extended thrombolysis in cerebral infarction [eTICI] 2C-3, FPR), functional independence [90-day modified Rankin Scale (mRS) score of 0-2] and mortality), aORs were reported. Adjusted β coefficients (aβ) were reported for 24-h NIHSS and procedure duration in minutes. Outcome differences between first-line treatment devices (stent retriever versus aspiration) were assessed with interaction terms.RESULTS: In 566 patients with M1 occlusions, thrombus density was not associated with reperfusion (acOR 1.01, 95% CI 0.99-1.02), FPR (aOR 1.01, 95% CI 0.99-1.03), mortality (aOR 0.98, 95% CI 0.95-1.00), 24-h NIHSS (aβ - 0.7%, 95% CI - 1.4-0.2), or procedure duration (aβ 0.27, 95% CI - 0.05-0.58). In multivariable analysis, thrombus density was associated with functional independence (aOR 1.02, 95% CI 1.00-1.05). No interaction was found between thrombus density and first-line treatment device for any outcome.CONCLUSION: In patients with M1 occlusions, thrombus density was not clearly associated with procedural and clinical outcomes after EVT.</p

Effect of first pass reperfusion on outcome in patients with posterior circulation ischemic stroke

BACKGROUND: First pass reperfusion (FPR), that is, excellent reperfusion (expanded treatment in cerebral ischemia (eTICI) 2C-3) in one pass, after endovascular treatment (EVT) of an occluded artery in the anterior circulation, is associated with favorable clinical outcome, even when compared with multiple pass excellent reperfusion (MPR). In patients with posterior circulation ischemic stroke (PCS), the same association is expected, but currently unknown. We aimed to assess characteristics associated with FPR and the influence of FPR versus MPR on outcomes in patients with PCS. METHODS: We used data from the MR CLEAN Registry, a prospective observational study. The effect of FPR on 24-hour National Institutes of Health Stroke Scale (NIHSS) score, as percentage reduction, and on modified Rankin Scale (mRS) scores at 3 months, was tested with linear and ordinal logistic regression models. RESULTS: Of 224 patients with PCS, 45 patients had FPR, 47 had MPR, and 90 had no excellent reperfusion (eTICI <2C). We did not find an association between any of the patient, imaging, or treatment characteristics and FPR. FPR was associated with better NIHSS (-45% (95% CI: -65% to -12%)) and better mRS scores (adjusted common odds ratio (acOR): 2.16 (95% CI: 1.23 to 3.79)) compared with no FPR. Outcomes after FPR were also more favorable compared with MPR, but the effect was smaller and not statistically significant (NIHSS: -14% (95% CI: -51% to 49%), mRS acOR: 1.50 (95% CI: 0.75 to 3.00)). CONCLUSIONS: FPR in patients with PCS is associated with favorable clinical outcome in comparison with no FPR. In comparison with MPR, the effect of FPR was no longer statistically significant. Nevertheless, our data support the notion that FPR should be the treatment target to pursue in every patient treated with EVT

Value of Automatically Derived Full Thrombus Characteristics:An Explorative Study of Their Associations with Outcomes in Ischemic Stroke Patients

(1) Background: For acute ischemic strokes caused by large vessel occlusion, manually assessed thrombus volume and perviousness have been associated with treatment outcomes. However, the manual assessment of these characteristics is time-consuming and subject to inter-observer bias. Alternatively, a recently introduced fully automated deep learning-based algorithm can be used to consistently estimate full thrombus characteristics. Here, we exploratively assess the value of these novel biomarkers in terms of their association with stroke outcomes. (2) Methods: We studied two applications of automated full thrombus characterization as follows: one in a randomized trial, MR CLEAN-NO IV (n = 314), and another in a Dutch nationwide registry, MR CLEAN Registry (n = 1839). We used an automatic pipeline to determine the thrombus volume, perviousness, density, and heterogeneity. We assessed their relationship with the functional outcome defined as the modified Rankin Scale (mRS) at 90 days and two technical success measures as follows: successful final reperfusion, which is defined as an eTICI score of 2b-3, and successful first-pass reperfusion (FPS). (3) Results: Higher perviousness was significantly related to a better mRS in both MR CLEAN-NO IV and the MR CLEAN Registry. A lower thrombus volume and lower heterogeneity were only significantly related to better mRS scores in the MR CLEAN Registry. Only lower thrombus heterogeneity was significantly related to technical success; it was significantly related to a higher chance of FPS in the MR CLEAN-NO IV trial (OR = 0.55, 95% CI: 0.31–0.98) and successful reperfusion in the MR CLEAN Registry (OR = 0.88, 95% CI: 0.78–0.99). (4) Conclusions: Thrombus characteristics derived from automatic entire thrombus segmentations are significantly related to stroke outcomes.</p

Endovascular Treatment for Posterior Circulation Stroke in Routine Clinical Practice:Results of the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry

BACKGROUND AND PURPOSE: The benefit of endovascular treatment (EVT) for posterior circulation stroke (PCS) remains uncertain, and little is known on treatment outcomes in clinical practice. This study evaluates outcomes of a large PCS cohort treated with EVT in clinical practice. Simultaneous to this observational study, several intervention centers participated in the BASICS trial (Basilar Artery International Cooperation Study), which tested the efficacy of EVT for basilar artery occlusion in a randomized setting. We additionally compared characteristics and outcomes of patients treated outside BASICS in trial centers to those from nontrial centers. METHODS: We included patients with PCS from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry: a prospective, multicenter, observational study of patients who underwent EVT in the Netherlands between 2014 and 2018. Primary outcome was a score of 0 to 3 on the modified Rankin Scale at 90 days. Secondary outcomes included reperfusion status and symptomatic intracranial hemorrhage. For outcome comparison between patients treated in trial versus nontrial centers, we used ordinal logistic regression analysis. RESULTS: We included 264 patients of whom 135 (51%) had received intravenous thrombolysis. The basilar artery was most often involved (77%). Favorable outcome (modified Rankin Scale score 0-3) was observed in 115/252 (46%) patients, and 109/252 (43%) patients died. Successful reperfusion was achieved in 178/238 (75%), and symptomatic intracranial hemorrhage occurred in 9/264 (3%). The 154 nontrial patients receiving EVT in BASICS trial centers had similar characteristics and outcomes as the 110 patients treated in nontrial centers (modified Rankin Scale adjusted cOR: 0.77 [95% CI, 0.5-1.2]). CONCLUSIONS: Our study shows that high rates of favorable clinical outcome and successful reperfusion can be achieved with EVT for PCS, despite high mortality. Characteristics and outcomes of patients treated in trial versus nontrial centers were similar indicating that our cohort is representative of clinical practice in the Netherlands. Randomized studies using modern treatment approaches are needed for further insight in the benefit of EVT for PCS

Automated Detection and Location Specification of Large Vessel Occlusion on Computed Tomography Angiography in Acute Ischemic Stroke

Background Fast and accurate detection of large vessel occlusions (LVOs) is crucial in selection of patients with acute ischemic stroke for endovascular treatment. We assessed accuracy of an automated LVO detection algorithm with LVO localization feature. Methods Consecutive patients who underwent computed tomography angiography in 2 centers between January 2018 and September 2019 and between June and November 2020 for suspected anterior circulation LVO were retrospectively included. Reference standard for presence and site of an anterior circulation LVO (intracranial internal carotid artery, M1, or M2 segments of the middle cerebral artery) was established by consensus of 2 independent neuroradiologist readings. All computed tomography angiographies were processed by StrokeViewer‐LVO, Nicolab. Accuracy of this algorithm with LVO localization feature was assessed. Results In total, computed tomography angiographies of 364 patients with suspected anterior circulation LVO were analyzed (mean age 67±15 years; 185 male patients). A total of 180 patients (49%) had an LVO (intracranial internal carotid artery [n=49 (27%)], M1 [n=91 (51%)], and M2 [n=40 (22%)]). Sensitivity and specificity for LVO detection were, respectively, 91% (95% CI, 86%–95%) and 87% (95% CI, 81%–91%). NPV and PPV were, respectively, 91% (95% CI, 86%–94%) and 87% (95% CI, 82%–91%). Accuracy of the LVO localization feature was 95%. Median upload‐to‐notification time was 04:31 (interquartile range, 04:21–05:50) minutes. Conclusions The automated LVO detection algorithm evaluated in this study, rapidly and accurately detected anterior circulation LVOs with high accuracy of the LVO localization feature. Therefore, it is a suitable screening tool to support and speed up diagnosis of stroke

Influence of time metrics on the treatment effect of intravenous alteplase prior to endovascular treatment in MR CLEAN-NO IV

Background: We assessed whether the treatment effect of intravenous alteplase (IVT) prior to endovascular treatment (EVT) on functional outcome is modified by time metrics. Methods: We used data from all patients included in MR CLEAN-NO IV, a randomized trial of IVT followed by EVT versus EVT alone in patients who presented directly to EVT-capable hospitals. The primary outcome was the modified Rankin Scale score at 90 days. We used ordinal regression with a multiplicative interaction term to assess if the effect of IVT is modified by onset-to-randomization (OTR), onset-to-IV-needle (OTN), door-to-groin (DTG) or needle-to-groin (NTG) times. Secondary outcomes included successful reperfusion (extended Thrombolysis In Cerebral Infarction Scale 2b-3) and symptomatic intracranial hemorrhage (sICH). Results: In 539 included patients (266 allocated to IVT+EVT and 273 to EVT alone), median workflow times were OTR: 93 (IQR 71-145) min; OTN: 98 (IQR 75-156) min; DTG: 64 (IQR 51-78) min; and NTG: 28 (IQR 20-41) min. There was a significant association between worse outcomes and longer time intervals for all metrics except NTG. We found no interaction between any of the time metrics and IVT for the effect on functional outcome (p values for interaction: OTR=0.40, OTN=0.39, DTG=0.61, NTG=0.56). We also did not observe any significant interaction for successful reperfusion or sICH. Conclusion: In MR CLEAN-NO IV, the effect of IVT prior to EVT was not modified by OTR, OTN, DTG or NTG times. Our results do not support the use of these metrics to guide IVT treatment decisions prior to EVT in comprehensive stroke centres. Trial registration number: ISRCTN80619088

Influence of time metrics on the treatment effect of intravenous alteplase prior to endovascular treatment in MR CLEAN-NO IV

Background: We assessed whether the treatment effect of intravenous alteplase (IVT) prior to endovascular treatment (EVT) on functional outcome is modified by time metrics. Methods: We used data from all patients included in MR CLEAN-NO IV, a randomized trial of IVT followed by EVT versus EVT alone in patients who presented directly to EVT-capable hospitals. The primary outcome was the modified Rankin Scale score at 90 days. We used ordinal regression with a multiplicative interaction term to assess if the effect of IVT is modified by onset-to-randomization (OTR), onset-to-IV-needle (OTN), door-to-groin (DTG) or needle-to-groin (NTG) times. Secondary outcomes included successful reperfusion (extended Thrombolysis In Cerebral Infarction Scale 2b-3) and symptomatic intracranial hemorrhage (sICH). Results: In 539 included patients (266 allocated to IVT+EVT and 273 to EVT alone), median workflow times were OTR: 93 (IQR 71-145) min; OTN: 98 (IQR 75-156) min; DTG: 64 (IQR 51-78) min; and NTG: 28 (IQR 20-41) min. There was a significant association between worse outcomes and longer time intervals for all metrics except NTG. We found no interaction between any of the time metrics and IVT for the effect on functional outcome (p values for interaction: OTR=0.40, OTN=0.39, DTG=0.61, NTG=0.56). We also did not observe any significant interaction for successful reperfusion or sICH. Conclusion: In MR CLEAN-NO IV, the effect of IVT prior to EVT was not modified by OTR, OTN, DTG or NTG times. Our results do not support the use of these metrics to guide IVT treatment decisions prior to EVT in comprehensive stroke centres. Trial registration number: ISRCTN80619088

Early recanalization in large-vessel occlusion stroke patients transferred for endovascular treatment

Background: We performed an exploratory analysis to identify patient and thrombus characteristics associated with early recanalization in large-vessel occlusion (LVO) stroke patients transferred for endovascular treatment (EVT) from a primary (PSC) to a comprehensive stroke center (CSC). Methods: We included patients with an LVO stroke of the anterior circulation who were transferred to our hospital for EVT and underwent repeated imaging between January 2016 and June 2019. We compared patient characteristics, workflow time metrics, functional outcome (modified Rankin Scale at 90 days), and baseline thrombus imaging characteristics, which included: occlusion location, thrombus length, attenuation, perviousness, distance from terminus of intracranial carotid artery to the thrombus (DT), and clot burden score (CBS), between early-recanalized LVO (ER-LVO), and non-early-recanalized LVO (NER-LVO) patients. Results: One hundred and forty-nine patients were included in the analysis. Early recanalization occurred in 32% of patients. ER-LVO patients less often had a medical history of hypertension (31% vs 49%, P=0.04), and more often had clinical improvement between PSC and CSC ( "NIHSS -5 vs 3, P<0.01), compared with NER-LVO patients. Thrombolysis administration was similar in both groups (88% vs 78%, P=0.18). ER-LVO patients had no ICA occlusions (0% vs 27%, P<0.01), more often an M2 occlusion (35% vs 17%, P=0.01), longer DT (27 mm vs 12 mm, P<0.01), shorter thrombi (17 mm vs 27 mm, P<0.01), and higher CBS (8 vs 6, P<0.01) at baseline imaging. ER-LVO patients had lower mRS scores (1 vs 3, P=0.02). Conclusions: Early recanalization is associated with clinical improvement between PSC and CSC admission, more distal occlusions and shorter thrombi at baseline imaging, and better functional outcome