Use of intravenous tissue-type plasminogen activator (IV tPA) for acute ischaemic stroke is restricted to patients with an INR < 1.7 though a recent study showed increased risk of symptomatic intracranial haemorrhage after IV tPA in those with oral anticoagulants (OAC) even with an INR <1.7. This study assessed the risk of symptomatic intracranial haemorrhage, clinical outcome, and mortality after intra-arterial therapy (IAT) in patients with and without previous use of OAC.

Consecutive patients (n= 714) treated with IAT from December 1992 to October 2010 were included in the study. Clinical outcome and mortality were assessed 90 days after stroke onset. Patients with and without previous use of OAC were compared.

The following findings were reported:

• 28 patients (3.9%) were on OAC at time of symptom onset.

• Median INR in the OAC group was 1.79 (interquartile range [IQR], 1.41–2.3) and 1.01 (IQR, 1.0–1.09; p <0.0001) in the group without OAC.

• Patients treated with OAC at admission underwent more often mechanical-only IAT than did patients without OAC (46.4% vs. 12.8%; p <0.0001).

• Comparing patients with and without previous use of OAC, there was no statistical difference in the rate of symptomatic intracranial haemorrhage (7.1% vs. 6.0%; p=0.80), unfavorable outcome (modified Rankin Scale score, 3 to 6; 67.9% vs. 50.9%; p= 0.11), and mortality (17.9% vs. 21.6%; p = 0.58).

The researchers conclude from these findings that “previous use of OAC did not significantly increase the risk of symptomatic intracranial hemorrhage after IAT or the risk of unfavorable outcome and mortality 90 days after IAT.”