Effect of anticoagulation on cardioembolic stroke severity, outcomes and response to intravenous thrombolysis

Area of Science:

• Neurology
• Cardiology
• Pharmacology

Background:

• Cardioembolic stroke (CS) is a significant cause of morbidity and mortality.
• The role of oral anticoagulants (OAC) in influencing CS severity and outcomes requires further elucidation.
• Understanding the impact of anticoagulation levels on treatment response, particularly intravenous thrombolysis (IVT), is crucial for patient management.

Purpose of the Study:

• To evaluate the effect of pre-stroke oral anticoagulation (OAC) and admission international normalized ratio (INR) on cardioembolic stroke (CS) severity.
• To assess the association between OAC and INR levels with 3-month outcomes (modified Rankin Scale - mRS) in CS patients.
• To determine if OAC influences the response to intravenous thrombolysis (IVT) in CS patients.

Main Methods:

• An observational study included 475 CS patients admitted to a Stroke Center between 2010 and 2013.
• Patients were categorized into three groups based on pre-stroke OAC and admission INR: <1.5, 1.5-1.9, and ≥2.
• Demographic data, vascular risk factors, symptomatic intracranial hemorrhage, stroke severity (NIHSS), and 3-month outcomes (mRS) were compared using multivariate analyses.

Main Results:

• An INR ≥2 on admission was associated with a higher probability of mild stroke (NIHSS <10) (OR 2.026).
• Previous OAC treatment (OR 2.109) and INR 1.5-1.9 (OR 3.676) were associated with favorable outcomes (mRS ≤2).
• In the subgroup of patients receiving IVT, OAC was not found to be related to stroke outcomes or response to IVT.

Conclusions:

• Therapeutic levels of oral anticoagulation (OAC) are associated with reduced cardioembolic stroke (CS) severity.
• Prior OAC treatment is linked to favorable 3-month outcomes in CS patients.
• Oral anticoagulation status does not appear to affect the response to intravenous thrombolysis (IVT) in CS patients.