Mortality Risk in Acute Ischemic Stroke Patients With Large Vessel Occlusion Treated With Mechanical Thrombectomy

Abstract

Background Recent randomized controlled clinical trials have provided solid evidence that mechanical thrombectomy (MT) coupled with best medical therapy (BMT) improve functional outcomes of acute ischemic stroke patients with large vessel occlusion compared with BMT alone. However, they provided inconclusive evidence on the benefit of MT on mortality. Methods and Results We evaluated the association of MT+BMT compared with BMT with the risk of 3-month mortality using aggregate data from all available randomized controlled clinical trials. We also sought to identify potential predictors on the mortality risk and performed univariate meta-regression analyses. Our literature search identified 11 eligible randomized controlled clinical trials, including a total of 2460 patients. The pooled rates of 3-month mortality were 15% (95% CI:12%-19%) and 19% (95% CI:16%-23%), respectively, in the MT+BMT and BMT groups. In the overall analysis MT+BMT was associated with a significantly lower risk for 3-month mortality compared with BMT (risk ratio=0.83, 95% CI:0.69-0.99; P=0.04), without heterogeneity across included studies (I²=3%, P for Cochran Q=0.41). No evidence of publication bias was present in funnel plot inspection and Egger statistical test (P=0.762). In meta-regression analyses no moderating effect on the aforementioned association was detected with patient age (P=0.254), sex (P=0.702), admission systolic blood pressure (P=0.601), admission glucose (P=0.277), onset-to-groin puncture time (P=0.985), administration of intravenous alteplase before MT (P=0.804), MT under general anesthesia (P=0.735), and successful reperfusion following MT (P=0.663). Conclusions Our meta-analysis provides evidence that MT+BMT reduces the risk of 3-month mortality compared with BMT alone. This association appears not to be moderated by individual patient or procedural characteristics.

Keywords: ischemic stroke; mortality; thrombectomy.

Figure 1

Forest plot on the risk of all‐cause mortality at 3 months between patients randomized to mechanical thrombectomy plus best medical treatment or best medical treatment alone. BMT indicates best medical therapy; DAWN, DWI or CTP Assessment with Clinical Mismatch in the Triage of Wake‐Up and Late Presenting Strokes Undergoing Neurointervention with Trevo; DEFUSE, Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke; ESCAPE, Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion with Emphasis on Minimizing CT to Recanalization Times; EXTEND‐IA, Extending the Time for Thrombolysis in Emergency Neurological Deficits — Intra‐Arterial; MR CLEAN, Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands; MT, mechanical thrombectomy; PISTE, Pragmatic Ischaemic Stroke Thrombectomy Evaluation; RESILIENT, Randomisation of endovascular treatment with stent‐retriever and/or thromboaspiration versus best medical therapy with acute ischaemic stroke due to large vessel occlusion; REVASCAT, Randomized Trial of Revascularization with Solitaire FR Device versus Best Medical Therapy in the Treatment of Acute Stroke Due to Anterior Circulation Large Vessel Occlusion Presenting within Eight Hours of Symptom Onset; SWIFT PRIME, Solitaire with the Intention for Thrombectomy as Primary Endovascular Treatment; THERAPY, The Randomized, Concurrent Controlled Trial to Assess the Penumbra System's Safety and Effectiveness in the Treatment of Acute Stroke; THRACE, Thrombectomie des Artères Cerebrales.

Figure 2

Forest plot on the probability of functional improvement at 3 months between patients randomized to mechanical thrombectomy plus best medical treatment vs best medical treatment alone. BMT indicates best medical therapy; DAWN, DWI or CTP Assessment with Clinical Mismatch in the Triage of Wake‐Up and Late Presenting Strokes Undergoing Neurointervention with Trevo; DEFUSE, Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke; ESCAPE, Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion with Emphasis on Minimizing CT to Recanalization Times; EXTEND‐IA, Extending the Time for Thrombolysis in Emergency Neurological Deficits — Intra‐Arterial; MR CLEAN, Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands; MT, mechanical thrombectomy; PISTE, Pragmatic Ischaemic Stroke Thrombectomy Evaluation; RESILIENT, Randomisation of endovascular treatment with stent‐retriever and/or thromboaspiration versus best medical therapy with acute ischaemic stroke due to large vessel occlusion; REVASCAT, Randomized Trial of Revascularization with Solitaire FR Device versus Best Medical Therapy in the Treatment of Acute Stroke Due to Anterior Circulation Large Vessel Occlusion Presenting within Eight Hours of Symptom Onset; SWIFT PRIME, Solitaire with the Intention for Thrombectomy as Primary Endovascular Treatment; THERAPY, The Randomized, Concurrent Controlled Trial to Assess the Penumbra System's Safety and Effectiveness in the Treatment of Acute Stroke; THRACE, Thrombectomie des Artères Cerebrales.