Intravenous Thrombolysis for Ischemic Stroke Patients on Dual Antiplatelets

Objective We assessed the outcomes of intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) patients on dual antiplatelet therapy prior to stroke onset. Methods We analyzed prospectively collected data from the Safe Implementation of Treatments in Stroke (SITS) International Stroke Thrombolysis Register on consecutive IVT‐treated AIS patients during a 7‐year period (2010–2017). In propensity score matched groups of patients with dual antiplatelet pretreatment and no antiplatelet pretreatment, we compared: (1) symptomatic intracerebral hemorrhage (SICH), according to SITS Monitoring Study (MOST), European Cooperative Acute Stroke Study (ECASS) II, and National Institute of Neurological Disorders and Stroke (NINDS) definitions; (2) 3‐month mortality; (3) 3‐month favorable functional outcome (FFO; modified Rankin Scale [mRS] scores = 0–1); (4) 3‐month functional independence (FI; mRS scores = 0–2); and (5) distribution of the 3‐month mRS scores. Dual antiplatelet pretreatment was defined as all possible combinations among aspirin, clopidogrel, dipyridamole, and any other antiplatelet. Results Propensity score matching resulted in 2 groups of 1,043 patients each, balanced for all baseline characteristics. In the propensity score matched analysis, the 2 groups had comparable (p > 0.017 using Bonferroni correction for multiple comparisons) SICH rates according to SITS‐MOST (2.9% vs 1.5%, 95% confidence interval [CI] = −0.03 to −0.01), ECASS II (5.2% vs 4.4%, 95% CI = −0.03 to 0.01), and NINDS (7.7% vs 6.6%, 95% CI = −0.03 to 0.01) definitions. No differences in the 3‐month mortality (17.9% vs 16.6%, 95% CI = −0.05 to 0.02), FFO (45.6% vs 46.0%, 95% CI = −0.04 to 0.05), FI (59.2% vs 60.7%, 95% CI = −0.03 to 0.06), or distribution in 3‐month mRS scores (2 [1–4] vs 2 [0–4], 95% CI = −0.29 to 0.09) were documented between the 2 groups. Interpretation Given that patients on dual antiplatelet pretreatment have similar SICH, 3‐month mortality rates, and functional outcomes compared to patients with no antiplatelet pretreatment, dual antiplatelet pretreatment history should not be used as a reason to withhold IVT in otherwise eligible AIS patients. Ann Neurol 2018;83:89–97