Long-Term Outcomes of Mechanical Thrombectomy for Stroke: A Meta-Analysis

Abstract

Mechanical thrombectomy (MT) has become the standard treatment for large vessel occlusion (LVO) in acute ischemic stroke (AIS). Few studies have investigated long-term outcomes for AIS treated with MT. Therefore, a pooled meta-analysis using data from randomized clinical trials (RCT) was performed to assess for long-term clinical outcomes. A systematic literature search was conducted on 27 September 2017, by searching the English literature in the Cochrane Library, MEDLINE, and Embase for RCTs investigating long-term outcomes (greater than standard 3-month timepoint) of endovascular intervention versus medical management for patients with AIS. The study was carried out according to PRISMA guidelines and random effects analysis was carried out to account for heterogeneity. Three trials were included: IMS III, MR CLEAN, and REVASCAT, comprising a total of 1,362 patients. Long-term clinical outcomes were available for 1-year follow-up in IMS III and REVASCAT and at 2 years in MR CLEAN. Functional independence at long-term follow-up favored endovascular stroke intervention (OR 1.51; p = 0.02). When stratified by LVO inclusion criteria, greater endovascular functional independence benefits were observed (OR 1.85; p = 0.0005). There was a significant difference between the 2 arms in favor of endovascular therapy for the quality of life at long-term follow-up (mean difference 0.11; p = 0.0002). No difference in mortality at long-term follow-up was observed (OR 0.82; p = 0.12). We conclude that endovascular therapy results in favorable outcomes at long-term follow-up for patients with acute ischemic stroke compared to standard medical treatment alone and that the 90-day timepoint offers a fair representation of the long-term outcomes.

Mechanical Thrombectomy using Distal Access Catheters: Current Status and Future Prospects

“…Aspiration devices achieve consistently high recanalization rates (68–100%), but clinical outcomes with aspiration are variable with studies showing very poor recovery rates 18 . ASTER trial showed no difference and no inferiority was shown in COMPASS trial and post‐hoc analysis of Mr CLEAN did not demonstrate any trends in outcome when comparing the two different approaches 19‐24 , 26 . While some evidence is emerging to suggest that either approach may be more efficient as a first line in different scenarios, for example, Ye et al reported 89% successful revascularisationusing ADAPT in basilar artery occlusion versus 83% using stent retreiver as first line, neurointerventionists have shifted strategy to combined approaches of which several are already reported in the literature 22,28 .…”

Biomechanics and hemodynamics of stent-retrievers

“…Stent-retriever thrombectomy shows that patients achieve high rates of good clinical outcome after 90-days 76 and there is evidence that this benefit over standard medical therapy persists for up to one year. 77 This may suggest, as do preclinical models, that the artery remodels and the injury is resolved. However, vascular imaging is not routinely acquired during long-term follow-up and vascular remodeling process in patients following stent-retriever thrombectomy remains largely unknown.…”

Post‐thrombectomy intracranial blooming artifact

“…Those that have been reported are symptomatic intracranial hemorrhage within 36 hours, subarachnoid hemorrhage (SAH), air emboli, vessel dissection, major groin complications, and emboli to new vascular territories. [1][2][3] We present a case of a patient who received mechanical thrombectomy, and on post procedure imaging was found to have artifact suggestive of a retained stent retriever or catheter remnant.…”

“…Complications from this procedure are uncommon. Those that have been reported are symptomatic intracranial hemorrhage within 36 hours, subarachnoid hemorrhage (SAH), air emboli, vessel dissection, major groin complications, and emboli to new vascular territories …”