Evaluation of mechanical thrombectomy in acute ischemic stroke related to a distal arterial occlusion: A randomized controlled trial.

RATIONALE: Mechanical thrombectomy (MT) associated with the best medical treatment (BMT) has recently shown efficacy for the management of acute ischemic stroke (AIS) secondary to a large vessel occlusion. However, evidence is lacking regarding the benefit of MT for more distal occlusions. AIM: To evaluate the efficacy in terms of good clinical outcome at 3 months of MT associated with the BMT over the BMT alone in AIS related to a distal occlusion. METHODS: The DISCOUNT trial is a multicenter open-label randomized controlled trial involving French University hospitals. Adult patients (⩾18 years) with an AIS involving the anterior or posterior circulation secondary to a distal vessel occlusion within 6 h of symptom onset or within 24 h if no hyperintense signal on fluid attenuation inversion recovery acquisition will be randomized 1:1 to receive either MT associated with the BMT (experimental group) or BMT alone (control group). The number of patients to be included is 488. STUDY OUTCOMES: The primary outcome is the rate of good clinical outcome at 3 months defined as a modified Rankin scale (mRS) ⩽2 and evaluated by an independent assessor blinded to the intervention arm. Secondary outcomes include recanalization of the occluded vessel within 48 h, angiographic reperfusion in the experimental group, 3-month excellent clinical outcome (mRS ⩽ 1), all adverse events, and death. A cost utility analysis will estimate the incremental cost per quality-adjusted life year (QALY) gained. DISCUSSION: If positive, this study will open new insights in the management of AISs. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05030142 registered on 1 September 2021.

Admission Blood Pressure and Outcome of Endovascular Therapy: Secondary Analysis of ASTER Trial.

BACKGROUND: Elevated blood pressure (BP) is common among patients presenting with acute ischemic stroke due to large vessel occlusions. The literature is inconsistent regarding the association between admission BP and outcome of mechanical thrombectomy (MT). Moreover, it is unclear whether the first line thrombectomy strategy (stent retriever [SR] versus contact aspiration [CA]) modifies the relationship between BP and outcome. METHODS: This is a post hoc analysis of the ASTER (Contact Aspiration Versus Stent Retriever for Successful Revascularization) randomized trial. BP was measured prior to randomization in all included patients. Co-primary outcomes included 90-day functional independence (modified Rankin Scale [mRS] 0-2) and successful revascularization (modified Treatment in Cerebral Ischemia [mTICI] 2b-3). Secondary outcomes included symptomatic intracerebral hemorrhage (sICH) and parenchymal hemorrhage (PH) within 24 hours. RESULTS: A total of 381 patients were included in the present study. Mean (SD) systolic BP (SBP) and diastolic BP (DBP) were 148 (26) mm Hg and 81 (16) mm Hg, respectively. There was no association between SBP or DBP and successful revascularization or 90-day functional independence. Similarly, there was no association between admission SBP or DBP with sICH or PH. Subgroup analysis based on the first-line thrombectomy strategy revealed similar results with no heterogeneity across groups. CONCLUSION: Admission BP was not associated with functional, angiographic or safety outcomes. Results were similar in both CA and CA groups.

Impact of infarct location on functional outcome following endovascular therapy for stroke.

OBJECTIVES: The relationship between stroke topography (ie, the regions damaged by the infarct) and functional outcome can aid clinicians in their decision-making at the acute and later stages. However, the side (left or right) of the stroke may also influence the identification of clinically relevant regions. We sought to determine which brain regions are associated with good functional outcome at 3 months in patients with left-sided and right-sided stroke treated by endovascular treatment using the diffusion-weighted imaging-Alberta Stroke Program Early CT Score (DWI-ASPECTS). METHODS: Patients with ischaemic stroke (n = 405) were included from the ASTER trial and Pitié-Salpêtrière registry. Blinded readers rated ASPECTS on day 1 DWI. Stepwise logistic regression analyses were performed to identify the regions related to 3-month outcome in left (n = 190) and right (n = 215) sided strokes with the modified Rankin scale (0-2) as a binary independent variable and with the 10 regions-of-interest of the DWI-ASPECTS as independent variables. RESULTS: Median National Institute of Health Stroke Scale (NIHSS) at baseline was 17 (IQR: 12-20), median age was 70 years (IQR: 58-80) and median day-one NIHSS 9 (IQR: 4-18). Not all brain regions have the same weight in predicting good outcome at 3 months; moreover, these regions depend on the affected hemisphere. In left-sided strokes, the multivariate analysis revealed that preservation of the caudate nucleus, the internal capsule and the cortical M5 region were independent predictors of good outcome. In right-sided strokes, the cortical M3 and M6 regions were found to be clinically relevant. CONCLUSION: Cortical non-motors areas related to outcome differed between left-sided and right-sided strokes. This difference might reflect the specialisation of the dominant and non-dominant hemispheres for language and attention, respectively. These results may influence decision-making at the acute and later stages. TRIAL REGISTRATION NUMBER: NCT02523261.

Similar Outcomes for Contact Aspiration and Stent Retriever Use According to the Admission Clot Burden Score in ASTER.

BACKGROUND AND PURPOSE: The clot burden score (CBS) at admission reliably evaluates the thrombus burden in acute ischemic stroke patients with anterior circulation large vessel occlusion. Mechanical thrombectomy has been diversified, especially with contact aspiration technique, and its efficiency with respect to the thrombus burden is not known. We compared reperfusion, adverse events, neurological recovery, and 90-day functional outcome of stent retriever use versus contact aspiration according to the admission CBS. METHODS: This is a post hoc analysis of the ASTER (Contact Aspiration Versus Stent Retriever for Successful Revascularization) randomized trial. The primary outcome was successful reperfusion after all procedures, defined as modified Thrombolysis in Cerebral Infarction scores 2b/3. Secondary outcomes were 90-day functional outcome, assessed with the modified Rankin Scale. Safety outcomes included 90-day mortality and any intracerebral hemorrhage. RESULTS: A total of 231 randomized patients were included in this study: 114 patients had a CBS of 0 to 6 and 117 a CBS ≥7 at admission. Successful reperfusion at procedure end was achieved more frequently in patients with CBS ≥7 (88.9%) than patients with a CBS 0 to 6 (81.6%; fully adjusted risk ratio, 1.09; 95% confidence interval, 1.01-1.28). Favorable outcome (modified Rankin Scale score, 0-2) at 90 days was achieved in significantly more patients with CBS ≥7 (61.9%) than in patients with CBS 0 to 6 (41.8%; fully adjusted risk ratio, 1.19; 95% confidence interval, 1.02-1.40). No outcome differences of first-line mechanical thrombectomy strategy (aspiration versus stent) on any angiographic or clinical outcomes were observed between the 2 groups. We also found no evidence of interaction between first-line mechanical thrombectomy strategy and CBS groups regarding safety. CONCLUSIONS: First-line mechanical thrombectomy with contact aspiration compared with stent retriever did not result in an increased successful reperfusion rate in acute ischemic stroke patients with large vessel occlusion of the anterior circulation according to the admission CBS. The latter, however, seems to be a reliable prognostic indicator of angiographic and clinical outcome.

Contact Aspiration Versus Stent Retriever in Patients With Acute Ischemic Stroke With M2 Occlusion in the ASTER Randomized Trial (Contact Aspiration Versus Stent Retriever for Successful Revascularization).

BACKGROUND AND PURPOSE: Middle cerebral artery M2-segment occlusions represent an important subgroup of patients with acute stroke with large-vessel occlusion. The safety of mechanical thrombectomy, especially contact aspiration (CA), in such distal intracranial occlusions is still under debate. We compared reperfusion, adverse events, neurological recovery, and functional outcome of patients with isolated M2 occlusions according to the first-line strategy mechanical thrombectomy devices (CA versus stent retriever [SR]). METHODS: This is a post hoc analysis of the ASTER trial (Contact Aspiration Versus Stent Retriever for Successful Revascularization). The primary outcome was successful reperfusion at the end of all endovascular procedures, defined as modified Thrombolysis in Cerebral Infarction (mTICI) scores 2b/3. Secondary outcomes were mTICI 2c/3 and mTICI 3, 90-day functional outcome, assessed with the modified Rankin Scale score. Safety outcomes included 90-day mortality and any symptomatic intracerebral hemorrhage. RESULTS: Seventy-nine patients were included: 48 were allocated to the CA group and 31 to the SR group. There were no significant differences between CA and SR groups in reperfusion after all endovascular procedures regarding mTICI 2b/3 (89.6% versus 83.9%; P=0.36), mTICI 2c/3 (54.2% versus 54.8%; P=0.90), and mTICI 3 (35.4% versus 41.9%; P=0.36) rates. There were no significant differences between CA and SR groups in 90-day modified Rankin Scale ≤2 rate (54.4% versus 50.0%; P=0.84), 24-hour change in National Institutes of Health Stroke Scale (mean difference, -3.9; 95% confidence interval, -7.9 to 0.01), and Alberta Stroke Program Early Computed Tomography score (mean difference, 0.9; 95% confidence interval, -0.1 to 2.0) scores. Safety parameters were well balanced between the 2 groups except for a higher 90-day mortality rate in the CA group (19.6% versus 3.3%; P=0.078). CONCLUSIONS: First-line mechanical thrombectomy with CA compared with SR did not result in an increased successful revascularization rate in patients with acute stroke with isolated M2 occlusion.

Effect of Endovascular Contact Aspiration vs Stent Retriever on Revascularization in Patients With Acute Ischemic Stroke and Large Vessel Occlusion: The ASTER Randomized Clinical Trial.

Importance: The benefits of endovascular revascularization using the contact aspiration technique vs the stent retriever technique in patients with acute ischemic stroke remain uncertain because of lack of evidence from randomized trials. Objective: To compare efficacy and adverse events using the contact aspiration technique vs the standard stent retriever technique as a first-line endovascular treatment for successful revascularization among patients with acute ischemic stroke and large vessel occlusion. Design, Setting, and Participants: The Contact Aspiration vs Stent Retriever for Successful Revascularization (ASTER) study was a randomized, open-label, blinded end-point clinical trial conducted in 8 comprehensive stroke centers in France (October 2015-October 2016). Patients who presented with acute ischemic stroke and a large vessel occlusion in the anterior circulation within 6 hours of symptom onset were included. Interventions: Patients were randomly assigned to first-line contact aspiration (n = 192) or first-line stent retriever (n = 189) immediately prior to mechanical thrombectomy. Main Outcomes and Measures: The primary outcome was the proportion of patients with successful revascularization defined as a modified Thrombolysis in Cerebral Infarction score of 2b or 3 at the end of all endovascular procedures. Secondary outcomes included degree of disability assessed by overall distribution of the modified Rankin Scale (mRS) score at 90 days, change in National Institutes of Health Stroke Scale (NIHSS) score at 24 hours, all-cause mortality at 90 days, and procedure-related serious adverse events. Results: Among 381 patients randomized (mean age, 69.9 years; 174 women [45.7%]), 363 (95.3%) completed the trial. Median time from symptom onset to arterial puncture was 227 minutes (interquartile range, 180-280 minutes). For the primary outcome, the proportion of patients with successful revascularization was 85.4% (n = 164) in the contact aspiration group vs 83.1% (n = 157) in the stent retriever group (odds ratio, 1.20 [95% CI, 0.68-2.10]; P = .53; difference, 2.4% [95% CI, -5.4% to 9.7%]). For the clinical efficacy outcomes (change in NIHSS score at 24 hours, mRS score at 90 days) and adverse events, there were no significant differences between groups. Conclusions and Relevance: Among patients with ischemic stroke in the anterior circulation undergoing thrombectomy, first-line thrombectomy with contact aspiration compared with stent retriever did not result in an increased successful revascularization rate at the end of the procedure. Trial Registration: clinicaltrials.gov Identifier: NCT02523261.