Abstract TP118: Recanalization After Extracranial Dissection Stratified by Medical Treatment: Antiplatelets versus Anticoagulation

Abstract

Objective: Dissection is a leading cause of stroke in young adults, though optimal antithrombotic management with either anticoagulation or antiplatelet therapy remains controversial. Existing data have focused on recurrent stroke but these studies have been underpowered. We aimed to assess recanalization rates for patients treated with anticoagulants compared to those treated with antiplatelet agents and to identify factors associated with vessel recanalization. Methods: We performed a retrospective, single center, cohort study, identifying patients with extracranial carotid or vertebral dissection, with acute and follow up imaging, over a 15 year period. Vessel stenosis was measured using NASCET methodology. Anticoagulation was defined as treatment with therapeutic Heparin or warfarin for greater than 50% of the first month. Univariable and multivariable analyses were performed to determine clinical, demographic, and radiographic factors associated with ≥ 50% relative recanalization at follow up. Results: We identified 75 patients with 84 dissections, mean age 47± SD 15, 43% female, 39% non-white. The rate of recurrent strokes was 2.7% in the entire cohort, which was not significantly different between treatment arms (p=0.35). Median time from symptom onset to first vessel imaging was 1 day (interquartile range [IQR] 0-6) and median time to follow up imaging was 4 months (IQR 3-7) after symptoms. Patients with higher percent stenosis at baseline were more likely to be treated with anticoagulation (median 99% vs. 50%, p=0.02). Comparing anticoagulation to antiplatelet therapy, there was no difference in the rates of ≥50% relative recanalization (50% vs 48%, p=0.84), nor in the absolute change (median 16% vs 7%, p=0.34) nor relative change (median 48% vs 43%, p=0.92) from baseline. In a multivariable model, antithrombotic therapy was not significantly associated with ≥ 50% recanalization. Hypertension was the only significant variable and was negatively associated with the outcome (OR 0.26, 95% confidence interval 0.09 - 0.72, p=0.009). Conclusions: Use of anticoagulation did not result in higher rates of recanalization, suggesting antiplatelet therapy is sufficient for the majority of patients with acute extracranial dissection.