Background and purpose: An elevated international normalized ratio (INR) of >1.7 is a contraindication for the use of intravenous thrombolytics in acute ischaemic stroke. Local intra-arterial therapy (IAT) is considered a safe alternative. The safety and outcome of IAT were investigated in patients with acute ischaemic stroke using oral anticoagulants (OACs).
Methods: Data were obtained from a large national Dutch database on IAT in acute stroke patients. Patients were categorized according to the INR: >1.7 and ≤1.7. Primary outcome was symptomatic intracerebral hemorrhage (sICH), defined as deterioration in the National Institutes of Health Stroke Scale score of ≥4 and ICH on brain imaging. Secondary outcomes were clinical outcome at discharge and 3 months. Occurrence of outcomes was compared with risk ratios and corresponding 95% confidence intervals. Further, a systematic review and meta-analysis on sICH risk in acute stroke patients on OACs treated with IAT was performed.
Results: Four hundred and fifty-six patients were included. Eighteen patients had an INR > 1.7 with a median INR of 2.4 (range 1.8-4.1). One patient in the INR > 1.7 group developed a sICH compared with 53 patients in the INR ≤ 1.7 group. Clinical outcomes did not differ between the two groups. Our meta-analysis showed a first week sICH risk of 8.1% in stroke patients with elevated INR treated with IAT.
Conclusion: The use of OACs, leading to an INR > 1.7, did not seem to increase the risk of an sICH in patients with an acute stroke treated with IAT.

Internationalized normalized ratio, Intra-arterial treatment, Meta-analysis, Oral anticoagulants, Thrombectomy,
European Journal of Neurology
Department of Neurology

Rozeman, A.D, Wermer, M.J.H, Lycklama à Nijeholt, G.J, Dippel, D.W.J, Schonewille, W.J, Boiten, J, & Algra, A. (2016). Safety of intra-arterial treatment in acute ischaemic stroke patients on oral anticoagulants. European Journal of Neurology, 23(2), 290–296. doi:10.1111/ene.12734