Not Too Late to Intervene? A Meta-analysis of 13 Studies Evaluating the Association of Endovascular Therapy with Clinical Outcomes in Stroke Patients Presenting Beyond 24 Hours

BackgroundAssociation of endovascular therapy (EVT) with clinical outcomes beyond 24 hours remains unclear. We conducted a meta-analysis to answer this question. MethodsWe searched for eligible studies in PubMed from inception until June 2023. The outcomes included functional independence, as assessed with 90-day modified Rankin Scale (mRS) scores (0-2), thrombolysis in cerebral infarction (TICI) scores (2b-3 or 3), symptomatic intracranial hemorrhage (sICH), and 90-day mortality. Risk ratio (RR) and 95% confidence interval (CI) were pooled. ResultsWe finally included 13 studies in our meta-analysis (number of patients treated with EVT beyond 24 h=866). For single arm analysis, the pooled estimates of functional independence (mRS 0-2), sICH, and mortality were 0.342 (95% CI = 0.275 -0.410, P < 0.001), 0.062 (95% CI = 0.045 -0.078, P < 0.001), and 0.232 (95% CI = 0.164 -0.301, P < 0.001); respectively with successful reperfusion (TICI 2b-3) of 0.837 (95% CI = 0.812 -0.861, P < 0.001). Comparing EVT with medical management, the pooled analysis showed that EVT had a statistically significant advantage over medical management (RR = 2.62, 95% CI [1.38, 4.96], P = 0.003). However, our analysis showed a higher incidence of sICH in EVT group (RR = 3.58, 95% CI [1.53, 8.37], P = 0.003). When we pooled studies comparing EVT beyond 24 h with EVT within 6-24 h, the findings showed no statistically significant difference for functional independence, sICH, and 90-d Mortality. ConclusionEVT is associated with better clinical outcomes than medical management beyond 24 hours. These results are iconoclastic enhancing a new paradigm in which a contemporary restriction to specific time window to treat patients rather than their own clinical and imaging characteristics seems to be anecdotal. Prospective studies are needed to confirm the best eligible patients for EVT in this newly proposed window extension.