Abstract
IntroductionAlthough endovascular treatment (EVT) is highly effective for acute ischemic strokes due to proximal large vessel occlusions (LVOs), its efficacy and safety in distal medium vessel occlusions (DMVOs) has shown conflicting results. EVT in distal medium vessel occlusions is considered high‐risk due to reduced vessel size and tortuosity, but newer techniques and recent efforts to explore the EVT potential have encouraged us to revisit thrombectomy indications. We thus performed a systematic review and meta‐analysis to compare its efficacy and safety with the best medical treatment (BMT) in treating primary DMVOs.MethodsA comprehensive search was performed on Embase, PubMed, and Cochrane from inception to April 2024. Efficacy outcomes of interest included functional independence (90‐day modified Rankin scale (mRS) 0‐2) and excellent functional outcomes (90‐day mRS 0‐1). Safety outcomes were symptomatic intracranial hemorrhage (sICH) and 90‐day mortality. Statistical analysis was performed on Review Manager (RevMan) version 5.3.ResultsTwo randomized controlled trials and twenty observational studies were included in this meta‐analysis with a total sample size of 4081; 1858 (46%) patients were included in the EVT arm and 2223 (54%) belonged to the BMT arm. In the overall cohort, EVT was comparable to BMT in terms of functional independence (OR 0.97, 95% CI 0.74 to 1.28, p=0.86), symptomatic ICH (OR 1.38, 95% CI 0.75 to 2.53), and mortality (OR 1.23, 95% CI: 0.88 to 1.70). A trend towards the superiority of EVT for excellent functional outcomes in strokes with NIHSS score >6 was observed but this finding missed statistical significance by a narrow margin (OR 1.22, 95% CI 0.96 to 1.56, p=0.10). An analysis of studies with mild strokes (NIHSS <6) showed that EVT leads to significantly lower rates of functional independence (OR 0.57, 95% CI 0.33 to 0.99, p=0.05) and also leads to significantly higher rates of sICH in these patients (OR 6.35, 95% CI 1.56 to 25.83, p=0.010).ConclusionBMT is comparable to EVT for distal medium vessel ischemic strokes (AIS‐DMVO). There may be a trend towards EVT achieving higher rates of excellent functional outcomes (mRS 0‐1) in patients with NIHSS score >6 but BMT is superior to EVT in patients with NIHSS score <6.