Efficacy and Safety of Mono Antiplatelet Treatment for Cardioembolic and Undetermined Etiological Stroke after Receiving Successful Mechanical Thrombectomy

Abstract Background Periprocedural antithrombotic medication after mechanical thrombectomy (MT) for acute intracranial large vessel occlusion (LVO) is still controversial. Recent studies have indicated that majority of stroke with undetermined etiology (SUE), as defined by the TOAST classification, showed strong overlap with cardioembolic stroke (CE). We intended to determine the efficacy of the mono antiplatelet (MA) therapy in both stroke types after receiving successful MT recanalization in the acute stage. Methods 178 consecutive stroke patients who received MT treatment were retrospectively analyzed. CE and SUE type stroke patients were chosed to received MA therapy. Aspirin 100mg or clopidogrel 75 mg was added immediate for patients who didn`t received intravenously recombinant tissue plasminogen activator (IV-rtPA) and after 24 hours for those received IV-rtPA if symptomatic intracranial hemorrhage (sICH) was not found. MA treatment outcomes included recanalized artery patency, subsequent sICH and functional independence (mRS score of 0-2) were compared between two stroke types. Results Successful recanalization (TICI 2b/3) was achieved in 75 CE stroke patients and 50 SUE patients without hemorrhagic transformation were included into final analysis. Target artery at 7 days after recanalization was confirmed 100% patency in the CE group and 97.5% in the SUE group. Hemorrhagic transformation after 24h was found in 26% patients in the SUE group and in 26.7% patients in the CE group (P > 0.05). sICH was confirmed in 3 patients in the SUE group and in 10 patients in the CE group. At 90 days, 45.8% in the SUE group and 46.5% in the CE group of patients had achieved good outcomes (mRs 0-2) (P=1.00). However, accumulative death was higher in the CE group than in the SUE group (21% vs. 15%; P=0.47) Conclusion Mono antiplatelet strategy for the treatment of accurate stage of cardioembolic stroke received mechanical thrombectomy is safe and effective. Meanwhile, for patients considered SUE stroke type, mono antiplatelet therapy after thrombectomy achieved similar treatment outcomes as compared to cardioembolic stroke patients.