Association of first-line thrombectomy technique and outcome in late-window large vessel occlusion strokes: A post hoc analysis of the MR CLEAN-LATE trial.

BACKGROUND: This study aimed to compare direct aspiration, stent retriever, and the combined thrombectomy technique on clinical, safety, and technical outcomes in late-window stroke patients included in the MR CLEAN-LATE trial. METHODS: This post hoc analysis of the MR CLEAN-LATE trial included patients treated with direct aspiration, stent retriever, or combined thrombectomy technique as first-line approach. Primary outcome was the modified Rankin Scale (mRS) score at 90 days follow-up, and compared between the three groups with ordinal logistic regression analysis. Secondary outcomes included mortality at 90 days, total technique switches, procedure time, recanalization rate measured with the expanded thrombolysis in cerebral infarction (eTICI) score, and symptomatic intracranial hemorrhage (sICH). Predefined variables were used for adjustments. RESULTS: In the MR CLEAN-LATE trial, 258 patients underwent endovascular treatment and 232 were included in our analyses. The mRS at 90 days did not differ (stent retriever vs. direct aspiration: adjusted common odds ratio (acOR) = 1.35, 95% confidence interval (CI) = 0.73 to 2.50; stent retriever vs. combined: acOR = 1.13, 95% CI = 0.64 to 2.00; direct aspiration vs. combined: acOR = 1.19, 95% CI = 0.64 to 2.21). Direct aspiration thrombectomy was accompanied with more switches to another technique compared to the stent retriever (adjusted odds ratio (aOR) = 6.50, 95% CI = 2.52 to 16.8) or combined group (aOR = 4.67, 95% CI = 1.80 to 12.1) and with higher sICH rates compared to the combined technique (13% vs. 2.5%; aOR = 8.19, 95% CI = 1.49 to 45.1). Mortality, procedure time, and eTICI did not differ. CONCLUSION: Stent retriever, direct aspiration, or the combined thrombectomy technique as first-line approach showed no differences in clinical outcome in late-window stroke patients. Direct aspiration was accompanied with higher sICH rates and more switcher to another technique compared to the combined group.

Sex differences in outcomes after endovascular treatment in posterior circulation stroke: results from the MR CLEAN Registry.

BACKGROUND: Women with anterior circulation large vessel occlusion (LVO) have been reported to have worse outcomes after endovascular treatment (EVT) than men. Whether these disparities also exist in LVO of the posterior circulation is yet uncertain. We assessed sex differences in clinical, technical, and safety outcomes of EVT in posterior circulation LVO. METHODS: We used data of patients with posterior circulation LVO included in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) Registry (2014-2018). Primary outcome was the modified Rankin Scale (mRS) score at 90 days assessed with multivariable ordinal regression analysis. Secondary outcomes included favorable functional outcome (mRS ≤3), functional independence (mRS ≤2), death within 90 days, National Institutes of Health Stroke Scale (NIHSS) score 24-48 hours postintervention, complications, successful reperfusion (extended Thrombolysis in Cerebral Ischemia 2B-3), and procedure duration analyzed with multivariable logistic and linear regression analyses. RESULTS: We included 264 patients (42% women). Compared with men, women were older (median age 68 vs 63 years), more often had prestroke disability (mRS ≥1: 37% vs 30%), and received intravenous thrombolytics less often (45% vs 56%). Clinical outcomes were similar between sexes (adjusted (common) OR (aOR) 0.82, 95% CI 0.51 to 1.34; favorable functional outcome 50% vs 43%, aOR 1.31, 95% CI 0.77 to 2.25; death 32% vs 29%, aOR 0.98, 95% CI 0.52 to 1.84). In addition, NIHSS score after 24-48 hours (median 7 vs 9), successful reperfusion (77% vs 73%), and complications did not differ between men and women. CONCLUSIONS: Outcomes in women treated with EVT for posterior circulation LVO were similar compared with men despite less favorable baseline characteristics in women. Therefore men and women may benefit equally from EVT.

Timing of symptomatic intracranial hemorrhage after endovascular stroke treatment.

Introduction: Little is known about the timing of occurrence of symptomatic intracranial hemorrhage (sICH) after endovascular therapy (EVT) for acute ischemic stroke. A better understanding could optimize in-hospital surveillance time points and duration. The aim of this study was to delineate the probability of sICH over time and to identify factors associated with its timing. Patients and methods: We retrospectively analyzed data from the Dutch MR CLEAN trial and MR CLEAN Registry. We included adult patients who underwent EVT for an anterior circulation large vessel occlusion within 6.5 h of stroke onset. In patients with sICH (defined as ICH causing an increase of ⩾4 points on the National Institutes of Health Stroke Scale [NIHSS]), univariable and multivariable linear regression analysis was used to identify factors associated with the timing of sICH. This was defined as the time between end of EVT and the time of first CT-scan on which ICH was seen as a proxy. Results: SICH occurred in 205 (6%) of 3391 included patients. Median time from end of EVT procedure to sICH detection on NCCT was 9.0 [IQR 2.9-22.5] hours, with a rapidly decreasing incidence after 24 h. None of the analyzed factors, including baseline NIHSS, intravenous alteplase treatment, and poor reperfusion at the end of the procedure were associated with the timing of sICH. Conclusion: SICHs primarily occur in the first hours after EVT, and less frequently beyond 24 h. Guidelines that recommend to perform frequent neurological assessments for at least 24 h after intravenous alteplase treatment can be applied to ischemic stroke patients treated with EVT.

Brain atrophy and endovascular treatment effect in acute ischemic stroke: a secondary analysis of the MR CLEAN trial.

BACKGROUND: Brain atrophy is suggested to impair the potential for functional recovery after acute ischemic stroke. We assessed whether the effect of endovascular treatment is modified by brain atrophy in patients with acute ischemic stroke due to large vessel occlusion. METHODS: We used data from MR CLEAN, a multicenter trial including patients with acute ischemic stroke due to anterior circulation large vessel occlusion randomized to endovascular treatment plus medical care (intervention) versus medical care alone (control). We segmented total brain volume (TBV) and intracranial volume (ICV) on baseline non-contrast computed tomography (n = 410). Next, we determined the degree of atrophy as the proportion of brain volume in relation to head size (1 - TBV/ICV) × 100%, analyzed as continuous variable and in tertiles. The primary outcome was a shift towards better functional outcome on the modified Rankin Scale expressed as adjusted common odds ratio. Treatment effect modification was tested using an interaction term between brain atrophy (as continuous variable) and treatment allocation. RESULTS: We found that brain atrophy significantly modified the effect of endovascular treatment on functional outcome (P for interaction = 0.04). Endovascular treatment led to larger shifts towards better functional outcome in the higher compared to the lower range of atrophy (adjusted common odds ratio, 1.86 [95% CI: 0.97-3.56] in the lowest tertile vs. 1.97 [95% CI: 1.03-3.74] in the middle tertile vs. 3.15 [95% CI: 1.59-6.24] in the highest tertile). CONCLUSION: Benefit of endovascular treatment is larger in the higher compared to the lower range of atrophy, demonstrating that advanced atrophy should not be used as an argument to withhold endovascular treatment.

Sensitivity of prehospital stroke scales for different intracranial large vessel occlusion locations.

INTRODUCTION: Prehospital stroke scales have been proposed to identify stroke patients with a large vessel occlusion to allow direct transport to an intervention centre capable of endovascular treatment (EVT). It is unclear whether these scales are able to detect not only proximal, but also more distal treatable occlusions. Our aim was to assess the sensitivity of prehospital stroke scales for different EVT-eligible occlusion locations in the anterior circulation. PATIENTS AND METHODS: The MR CLEAN Registry is a prospective, observational study in all centres that perform EVT in the Netherlands. We included adult patients with an anterior circulation stroke treated between March 2014 and November 2017. We used National Institutes of Health Stroke Scale scores at admission to reconstruct previously published prehospital stroke scales. We compared the sensitivity of each scale for different occlusion locations. Occlusions were assessed with CT angiography by an imaging core laboratory blinded to clinical findings. RESULTS: We included 3021 patients for the analysis of 14 scales. All scales had the highest sensitivity to detect internal carotid artery terminus occlusions (ranging from 0.21 to 0.97) and lowest for occlusions of the M2 segment (0.08 to 0.84, p-values < 0.001).Discussion and conclusion: Although prehospital stroke scales are generally sensitive for proximal large vessel occlusions, they are less sensitive to detect more distal occlusions.

Prior antiplatelet therapy in patients undergoing endovascular treatment for acute ischemic stroke: Results from the MR CLEAN Registry.

BACKGROUND: Antiplatelet therapy may increase the risk of symptomatic intracranial hemorrhage after endovascular treatment for ischemic stroke but may also have a beneficial effect on functional outcome. The aim of this study is to compare safety and efficacy outcomes after endovascular treatment in patients with and without prior antiplatelet therapy. METHODS: We analyzed patients registered in the MR CLEAN Registry between March 2014 and November 2017, for whom data on antiplatelet therapy were available. We used propensity score nearest-neighbor matching with replacement to balance the probability of receiving prior antiplatelet therapy between the prior antiplatelet therapy and no prior antiplatelet therapy group and adjusted for baseline prognostic factors to compare these groups. Primary outcome was symptomatic intracranial hemorrhage. Secondary outcomes were 90-day functional outcome (modified Rankin Scale), successful reperfusion (extended thrombolysis in cerebral infarction score ≥2B) and 90-day mortality. RESULTS: Thirty percent (n = 937) of the 3154 patients were on prior antiplatelet therapy, who were matched to 477 patients not on prior antiplatelet therapy. Symptomatic intracranial hemorrhage occurred in 74/937 (7.9%) patients on prior antiplatelet therapy and in 27/477 (5.6%) patients without prior antiplatelet therapy adjusted odds ratio 1.47, 95% confidence interval 0.86-2.49. No associations were found between prior antiplatelet therapy and functional outcome (adjusted common odds ratio 0.87, 95% confidence interval 0.65-1.16), successful reperfusion (adjusted odds ratio 1.23, 95% confidence interval 0.77-1.97), or 90-day mortality (adjusted odds ratio 1.15, 95% confidence interval 0.86-1.54). CONCLUSION: We found no evidence of an association of prior antiplatelet therapy with the risk of symptomatic intracranial hemorrhage after endovascular treatment, nor on functional outcome, reperfusion, or mortality. A substantial beneficial or detrimental effect of antiplatelet therapy on clinical outcome cannot be excluded. A randomized clinical trial comparing antiplatelet therapy versus no antiplatelet therapy is needed.

Impact of single phase CT angiography collateral status on functional outcome over time: results from the MR CLEAN Registry.

BACKGROUND: Collateral status modified the effect of endovascular treatment (EVT) for stroke in several randomized trials. We assessed the association between collaterals and functional outcome in EVT treated patients and investigated if this association is time dependent. METHODS: We included consecutive patients from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in The Netherlands (MR CLEAN) Registry (March 2014-June 2016) with an anterior circulation large vessel occlusion undergoing EVT. Functional outcome was measured on the modified Rankin Scale (mRS) at 90 days. We investigated the association between collaterals and mRS in the MR CLEAN Registry with ordinal logistic regression and if this association was time dependent with an interaction term. Additionally, we determined modification of EVT effect by collaterals compared with MR CLEAN controls, and also investigated if this was time dependent with multiplicative interaction terms. RESULTS: 1412 patients were analyzed. Functional independence (mRS score of 0-2) was achieved in 13% of patients with grade 0 collaterals, in 27% with grade 1, in 46% with grade 2, and in 53% with grade 3. Collaterals were significantly associated with mRS (adjusted common OR 1.5 (95% CI 1.4 to 1.7)) and significantly modified EVT benefit (P=0.04). None of the effects were time dependent. Better collaterals corresponded to lower mortality (P<0.001), but not to lower rates of symptomatic intracranial hemorrhage (P=0.14). CONCLUSION: In routine clinical practice, better collateral status is associated with better functional outcome and greater treatment benefit in EVT treated acute ischemic stroke patients, independent of time to treatment. Within the 6 hour time window, a substantial proportion of patients with absent and poor collaterals can still achieve functional independence.

Successful mechanical thrombectomy in a comatose patient with cerebral venous sinus thrombosis: A case report.

Cerebral venous sinus thrombosis is a rare cause of stroke, which is routinely treated with systemic heparin. Unfavourable outcome is often seen in severe cases. Therefore alternative treatment methods should be explored in these patients. Due to the risk of haemorrhagic complications, treatment without administration of thrombolytics is of particular interest. This report presents a case of successful mechanical thrombectomy, without the use of thrombolytics, in a comatose patient with cerebral venous sinus thrombosis.