Impact of Atrial Fibrillation on Outcomes in Stroke Patients with Tandem Occlusions Treated with Thrombectomy.A multicentre study.

Background. Tandem occlusions, involving simultaneous extracranial and intracranial artery blockages, represent a complex subtype of acute ischemic stroke treated with mechanical thrombectomy (MT). However, to date, the impact of atrial fibrillation (AF) on outcomes in this population remains unclear. This study aimed to evaluate the safety and efficacy of MT in patients with tandem occlusions, comparing those with AF to their counterparts without AF. Methods. We performed a multicentre, retrospective study using inverse probability weighting (IPW) to evaluate the effect of AF on outcomes in tandem occlusion patients treated with MT across three comprehensive stroke centres. The primary outcome was functional independence at 90 days (modified Rankin Scale [mRS] 0–2). Secondary outcomes included recanalization success (TICI ≥2b), intracranial hemorrhage (ICH), symptomatic ICH (sICH), and 90-day mortality. Subgroup analyses assessed the interaction between AF and clinical or procedural factors. Results. Among 635 patients, 164 (25.8%) had AF (TandemAF). TandemAF patients had significantly lower rates of favourable 90-day functional outcomes (adjusted risk ratio [aRR] 0.49 [95% CI 0.31–0.76]; p = 0.001) and higher 90-day mortality (aRR 2.29 [95% CI 1.47–3.55]; p < 0.001) compared to non-AF patients. Rates of successful recanalization, ICH, and sICH were similar between groups. Subgroup analysis revealed worse outcomes for TandemAF patients aged ≥65 years, with NIHSS 11–42, and those treated with general anesthesia or intravenous thrombolysis. Conclusions. Patients with tandem occlusion and AF undergoing MT showed significantly worse functional and survival outcomes relative to their non-AF counterparts, despite comparable procedural success rates. These findings highlight the critical need for tailored management strategies to mitigate the unique risks associated with AF in this population. Further research is essential to refine therapeutic approaches and improve outcomes for this high-risk group.