Background: and Purpose Effect of endovascular therapy (EVT) in acute large vessel occlusion (LVO) patients with tandem lesions (TLs) within 6–24 hours after last known well (LKW) remains unclear. We evaluated the clinical and safety outcomes among TL-LVO patients treated within 6–24 hours. Methods: This multicenter cohort was divided into two groups, based on LKW to puncture time: early window (<6 hours), and late window (6–24 hours). Primary clinical and safety outcomes were 90-day functional independence measured by the modified Rankin Scale (mRS: 0–2) and symptomatic intracranial hemorrhage (sICH). Secondary outcomes were successful reperfusion (modified Thrombolysis in Cerebral Infarction score ≥2b), first-pass effect, early neurological improvement, ordinal mRS, and in-hospital and 90-day mortality. Results: Of 579 patients (median age 68, 32.1% females), 268 (46.3%) were treated in the late window and 311 (53.7%) in the early window. Late window group had lower median National Institutes of Health Stroke Scale score at admission, Alberta Stroke Program Early Computed Tomography Score, rates of intravenous thrombolysis, and higher rates for perfusion imaging. After adjusting for confounders, the odds of 90-day mRS 0–2 (47.7% vs. 45.0%, adjusted odds ratio [aOR] 0.71, 95% confidence interval [CI] 0.49–1.02), favorable shift in mRS (aOR 0.88, 95% CI 0.44–1.76), and sICH (3.7% vs. 5.2%, aOR 0.56, 95% CI 0.20–1.56) were similar in both groups. There was no difference in secondary outcomes. Increased time from LKW to puncture did not predicted the probability of 90-day mRS 0–2 (aOR 0.99, 95% CI 0.96–1.01, for each hour delay) among patients presenting <24 hours. Conclusion EVT for acute TL-LVO treated within 6–24 hours after LKW was associated with similar rates of clinical and safety outcomes, compared to patients treated within 6 hours.

Background: and Purpose Outcomes following mechanical thrombectomy (MT) are strongly correlated with successful recanalization, traditionally defined as modified Thrombolysis in Cerebral Infarction (mTICI) ≥2b. This retrospective cohort study aimed to compare the outcomes of patients with low Alberta Stroke Program Early Computed Tomography Score (ASPECTS; 2–5) who achieved mTICI 2b versus those who achieved mTICI 2c/3 after MT. Methods: This study utilized data from the Stroke Thrombectomy and Aneurysm Registry (STAR), which combined databases from 32 thrombectomy-capable stroke centers between 2013 and 2023. The study included only patients with low ASPECTS who achieved mTICI 2b, 2c, or 3 after MT for internal carotid artery or middle cerebral artery (M1) stroke. Results: Of the 10,229 patients who underwent MT, 234 met the inclusion criteria. Of those, 98 (41.9%) achieved mTICI 2b, and 136 (58.1%) achieved mTICI 2c/3. There were no significant differences in baseline characteristics between the two groups. The 90-day favorable outcome (modified Rankin Scale score: 0–3) was significantly better in the mTICI 2c/3 group than in the mTICI 2b group (adjusted odds ratio 2.35; 95% confidence interval [CI] 1.18–4.81; P=0.02). Binomial logistic regression revealed that achieving mTICI 2c/3 was significantly associated with higher odds of a favorable 90-day outcome (odds ratio 2.14; 95% CI 1.07–4.41; P=0.04). Conclusion In patients with low ASPECTS, achieving an mTICI 2c/3 score after MT is associated with a more favorable 90-day outcome. These findings suggest that mTICI 2c/3 is a better target for MT than mTICI 2b in patients with low ASPECTS.