Thrombectomy in ischemic stroke patients with tandem occlusion in the posterior versus anterior circulation

Background Mechanical thrombectomy (MT) was found to be beneficial in acute ischemic stroke patients with anterior tandem occlusion (a-TO). Instead, little is known about the effectiveness of MT in stroke patients with posterior tandem occlusion (p-TO). We aimed to compare MT within 24 h from last known well time in ischemic stroke patients with p-TO versus a-TO. Methods We conducted a cohort study on prospectively collected data of patients registered in the Italian Registry of Endo- vascular Treatment in Acute Stroke (IRETAS) who were treated with MT within 24 h from last known well time for acute ischemic stroke with p-TO (n = 275) or a-TO (n = 1853). Results After adjustment for unbalanced pre-procedure variables (year 2015–2021, age, sex, NIHSS score, ASPECTS, and time strata for puncture groin) and pre-stroke mRS score as pre-defined predictor, p-TO was significantly associated with lower probability of mRS score 0–2 (OR 0.415, 95% CI 0.268–0.644) and with higher risk of death (OR 2.813, 95% CI 2.080–3.805) at 3 months. After adjustment for unbalanced procedural and post-procedure variables (IVT, general anesthesia, TICI 3, and 24-h HT) and pre-stroke mRS score as pre-defined predictor, association between p-TO and lower probability of mRS score 0–2 (OR 0.444, 95% CI 0.304–0.649) and association between p-TO and with higher risk of death (OR 2.971, 95% CI 1.993–4.429) remained significant. Conclusions MT within 24 h from last known well time in ischemic stroke patients with p-TO versus a-TO was associated with worse outcomes at 3 months.