Abstract Body: INTRODUCTION: An optimal strategy for the treatment of intracranial atherosclerotic disease (ICAD) has remained unclear, despite medical therapy (antiplatelet therapy and LDL control management) or endovascular therapy (angioplasty or stenting). Recently, cilostazol plus other antiplatelet agents combined therapy (CT) has been reported to reduce recurrent stroke, and eicosapentaenoic acid (EPA) has been reported to reduce the risk of cardiovascular events and plaque progression. Therefore, our hypothesis is that the addition of CT and EPA therapy may reduce stroke recurrence and further regression of stenosis.

METHODS: Patients with symptomatic and asymptomatic intracranial artery stenosis treated and followed at our institution from January 2009 to December 2023 were included in this study: 198 ICAD lesions in 155 patients (mean follow-up 11 months) were retrospectively evaluated. Each patient was divided into antiplatelet therapy alone (AA) (monotherapy (MT) or CT), antiplatelet therapy plus statin (AS), and antiplatelet therapy plus statin and EPA (AE). Antiplatelet drug monotherapy was aspirin, clopidogrel, or prasugrel and combination therapy was any of them plus cilostazol. ICAD was assessed by MRA and the stenosis rate was calculated by the warfarin-aspirin symptomatic intracranial disease (WASID) method.

RESULTS: The improvement in stenosis was significantly better with CT than with MT (Median% interquartile range(IQR)= CT: 21.71% (11.33-41.40) vs. MT: 9.15% (2.69-25.78), P<0.0001 Mann-Whitney test). Within the CT group, the AE group showed the greatest improvement in stenosis (Median% (IQR)= AA: 10.95% (5.55-30.45) vs AS: 20.41% (12.54-41.26) vs AE: 25.51% (14.11-42.55), Kruskal-Wallis test p:0.0181), while there were no significant differences between the MT groups (Kruskal-Wallis test p:0.7185). Stroke recurrence rates were 16.2% in the AA group, 13.8% in the AS group, and 5.9% in the AE group, with no significant difference, but a trend toward lower recurrence rates in the AE group was observed; in a comparison of the CT+AE group with the MT+AA group, the CT+AE group had significantly lower recurrence rates than the MT+AA group (Fisher's exact test P: 0.0455).

CONCLUSION: Cilostazol and EPA added to the conventional therapy was associated with less stroke recurrence, and it also showed significant regression in ICAD. Larger studies should investigate the role of cilostazol and EPA in stroke recurrence and plaque regression.