This study included 180 consecutive MT cases at a high-volume stroke center from February 2015 to June 2017. A retrospective chart review was conducted to identify patient sociodemographics, presence of AF, use of anticoagulation, stroke severity, CHA₂DS₂-VASc scores, and functional outcome. 

AF was present in 91 (50.6%) cases. Compared to patients without AF, patients with AF were older (mean 78.8±10.4 years vs. 66.7±14.1 years) and 59.5% were women. Initial NIHSS score was similar between the two groups (17.1±5.5 vs. 15.8±6.6; P=0.17). In the AF group, 52 (29%) patients had a previous diagnosis of AF and of these, 33 (63.4%) patients were not on OAC. Of those on warfarin, 6/7 (85.7%) were subtherapeutic with INR < 2.0. Of those on a direct oral anticoagulant, 3/12 (25%) were non-adherent and received intravenous alteplase. Of the 33 patients with prior diagnosis of AF not on OAC, 3 (9%) had CHA₂DS₂-VASc score ≤1 and aspirin may have been an alternative. There was no difference in functional outcome between the AF vs. non-AF groups in terms of NIHSS score at 24-36 hours (13.4±8.3 vs. 13.0±9.3 [P=0.73]) and modified Rankin Scale score (4.1±1.7 vs. 3.67±1.8 [P=0.11]) at discharge.

In our study, 39 (21.7%) patients with LVO undergoing MT had known AF and were not adequately treated. Approximately 1 in 5 thrombectomy cases in our study could have been avoided with improved stroke prevention measures. Further research is necessary to understand barriers to OAC in patients with AF.