title: Safety of intra-arterial treatment in acute ischaemic stroke patients on oral anticoagulants. A cohort study and systematic review.
abstract: OBJECTIVE
  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 (6%) in the INR > 1.7 group developed a sICH compared with 53 patients (12%) in the INR ≤ 1.7 group (risk ratio 0.49, 95% confidence interval 0.07-3.13). Clinical outcomes did not differ between the two groups. Our meta-analysis showed a first week sICH risk of 8.1% (95% confidence interval 3.9%-17.1%) in stroke patients with elevated INR treated with IAT.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Neurology, MC Haaglanden, The Hague, The Netherlands.
authors.forename: A D
authors.initials: AD
authors.lastname: Rozeman
authors.affiliation: Department of Neurology, LUMC, Leiden, The Netherlands.
authors.forename: M J H
authors.initials: MJ
authors.lastname: Wermer
authors.affiliation: Department of Radiology, MC Haaglanden, The Hague, The Netherlands.
authors.forename: G J
authors.initials: GJ
authors.lastname: Lycklama à Nijeholt
authors.affiliation: Department of Neurology, Erasmus MC, Rotterdam, The Netherlands.
authors.forename: D W J
authors.initials: DW
authors.lastname: Dippel
authors.affiliation: Department of Neurology, St Antonius Hospital, Nieuwegein, The Netherlands.|Brain Center Rudolf Magnus, Department of Neurology and Neurosurgery, UMC Utrecht, Utrecht, The Netherlands.
authors.forename: W J
authors.initials: WJ
authors.lastname: Schonewille
authors.affiliation: Department of Neurology, MC Haaglanden, The Hague, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Boiten
authors.affiliation: Brain Center Rudolf Magnus, Department of Neurology and Neurosurgery, UMC Utrecht, Utrecht, The Netherlands.|Department of Clinical Epidemiology, LUMC, Leiden, The Netherlands.
authors.forename: A
authors.identifier: http://orcid.org/0000-0003-2858-5808
authors.initials: A
authors.lastname: Algra
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D002545:Brain Ischemia / Q000188:drug therapy*; D002648:Child; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007261:Infusions, Intra-Arterial; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D020521:Stroke / Q000188:drug therapy*; D014481:United States; D055815:Young Adult
chemical_list: D000925:Anticoagulants
keywords: internationalized normalized ratio; intra-arterial treatment; meta-analysis; oral anticoagulants; thrombectomy