Endovascular Treatment for Acute Ischemic Stroke in Patients on Oral Anticoagulants

Abstract

Background and Purpose— The use of oral anticoagulants (OAC) is considered a contra-indication for intravenous thrombolytics as acute treatment of ischemic stroke. However, little is known about the risks and benefits of endovascular treatment in patients on prior OAC. We aim to compare outcomes after endovascular treatment between patients with and without prior use of OAC. Methods— Data of patients with acute ischemic stroke caused by an intracranial anterior circulation occlusion, included in the nationwide, prospective, MR CLEAN Registry between March 2014 and November 2017, were analyzed. Outcomes of interest included symptomatic intracranial hemorrhage and functional outcome at 90 days (modified Rankin Scale score). Outcomes between groups were compared with (ordinal) logistic regression analyses, adjusted for prognostic factors. Results— Three thousand one hundred sixty-two patients were included in this study, of whom 502 (16%) used OAC. There was no significant difference in the occurrence of symptomatic intracranial hemorrhage between patients with and without prior OACs (5% versus 6%; adjusted odds ratio, 0.63 [95% CI, 0.38–1.06]). Patients on OACs had worse functional outcomes than patients without OACs (common odds ratio, 0.57 [95% CI, 0.47–0.66]). However, this observed difference in functional outcome disappeared after adjustment for prognostic factors (adjusted common odds ratio, 0.91 [95% CI, 0.74–1.13]). Conclusions— Prior OAC use in patients treated with endovascular treatment for ischemic stroke is not associated with an increased risk of symptomatic intracranial hemorrhage or worse functional outcome compared with no prior OAC use. Therefore, prior OAC use should not be a contra-indication for endovascular treatment.

Oral Anticoagulation and Risk of Symptomatic Hemorrhagic Transformation in Stroke Patients Treated With Mechanical Thrombectomy: Data From the Nordictus Registry

“…However, only seven patients had a value of INR >3, so this precludes any conclusion. On the other hand, our result is in agreement with previous works showing that increased INR was not associated with higher sICH risk (6)(7)(8)18). Thus, pretreatment INR level may not reflect the risk of bleeding after EVT, and therefore exclusion of EVT candidates based on INR level, as done with intravenous thrombolysis patients, does not seem to be justified according to existing evidence.…”

“…Future research should address these issues (1,16). Use of VKA was associated with worse functional outcome at 3 months in bivariate analysis but did not predict functional dependence in the multivariate regression model, in accordance with a recent study (6). This lack of association with poor functional outcome could be due to the role of confounding factors associated with the use of VKA, such as age, comorbidities, premorbid status, or higher incidence of atrial fibrillation (17) in patients under VKA treatment compared with nonanticoagulated patients.…”

“…Moreover, recanalization rates were also similar in the two groups. Other series have reported better TICI scores in patients receiving OAC, raising the prospect that anticoagulation itself may reduce fibrin formation and facilitate EVT (6) or that thrombus from cardioembolic origin could be more prone to be removed (20), but this is unclear (21). According to our results, we can affirm that EVT is safe and feasible in the context of previous anticoagulation as previously reported (22).…”

“…Adjustment was performed for all variables showing a p < 0.1 on the respective bivariate analysis. Age, arterial hypertension, dyslipidemia, and atrial fibrillation were also entered into the model as relevant potential confounding factors derived from recent literature (6) and from our bivariate analysis of variables associated with prior OAC. We performed a subgroup analysis to evaluate the influence of the type of anticoagulant (VKA vs. DOACs) on the outcomes.…”

“…In addition, there is little data regarding the possible influence of the type of anticoagulant (VKA vs. DOACs) and the risk of sICH after EVT in AIS. Recently, a systematic review and meta-analysis demonstrated that patients under VKA treatment had an increased risk of sICH and mortality after mechanical thrombectomy (1), although another observational study did not report differences in the rates of sICH between patients under VKA compared with DOACs (6).…”