Abstract DP291: Updated Meta-Analysis Of 2,897 Patients Comparing Antegrade Versus Retrograde Approaches In Endovascular Treatment For Large Vessel Occlusion Stroke With Tandem Lesions.

Background: There is no consensus on whether emergent carotid artery stenting should be performed before (antegrade approach) or after (retrograde approach) endovascular thrombectomy for tandem lesions, defined as concomitant intracranial large vessel occlusion with cervical artery severe stenosis or occlusion. This updated systematic review and meta-analysis sought to compare the two approaches to provide updated clinical evidence on strategy selection. Methods: A comprehensive literature search was conducted across PubMed, Embase, and Cochrane databases from inception through May 20th, 2025. Comparative studies of antegrade vs retrograde approaches were included. Outcomes analyzed included successful recanalization (thrombolysis in cerebral infarction score 2b-3), procedural complications, symptomatic intracranial hemorrhage (sICH), 90-day good functional outcome (modified Rankin scale 0-2), and 90-day mortality. Random-effects model was used, with heterogeneity assessed by I 2 statistics. Results: Nineteen studies (n = 2987; 1,479 antegrade; 1,418 retrograde) were included (Figure 1). The antegrade approach was less likely to achieve successful recanalization (OR: 0.71; CI: 0.54-0.95; p = 0.02; I 2 = 41.0%, Figure 2). The antegrade approach also had significantly longer puncture-to-recanalization time (MD: 14.90; CI: 5.44-24.35; p < 0.01; I 2 = 70.9%) and longer overall procedural times (MD: 14.76; CI: 10.79-18.74; p < 0.01; I 2 = 48.0%, Figure 3). The retrograde approach was associated with significantly higher rates of good functional outcomes in a leave-one-out sensitivity analysis (OR: 0.79; CI: 0.64-0.98; p = 0.03; I 2 = 20.0%). No significant differences were observed in sICH (RR: 1.04; CI: 0.70-1.53; p = 0.849, I 2 = 0.0%) or 90-day mortality (RR 1.07; CI: 0.88–1.28; p = 0.506; I 2 = 4.0%). Conclusion: This large, updated meta-analysis supports that the retrograde approach may be better and faster at achieving successful recanalization with improved long-term functional outcomes, while having a similar procedural safety profile compared to the antegrade approach. Further prospective studies and randomized controlled trials are warranted to confirm these findings.