Dual antiplatelet therapy pretreatment in IV thrombolysis for acute ischemic stroke.

Abstract

We sought to determine the safety and efficacy of IV thrombolysis (IVT) in acute ischemic stroke (AIS) patients with a history of dual antiplatelet therapy pretreatment (DAPP) in a prospective multicenter study. We compared the following outcomes between DAPP+ and DAPP- IVT-treated patients before and after propensity score matching (PSM): symptomatic intracranial hemorrhage (sICH), asymptomatic intracranial hemorrhage, favorable functional outcome (modified Rankin Scale score 0-1), and 3-month mortality. Among 790 IVT patients, 58 (7%) were on DAPP before stroke (mean age 68 ± 13 years; 57% men; median NIH Stroke Scale score 8). DAPP+ patients were older with more risk factors compared to DAPP- patients. The rates of sICH were similar between groups (3.4% vs 3.2%). In multivariable analyses adjusting for potential confounders, DAPP was associated with higher odds of asymptomatic intracranial hemorrhage (odds ratio = 3.53, 95% confidence interval: 1.47-8.47; <i>p</i> = 0.005) but also with a higher likelihood of 3-month favorable functional outcome (odds ratio = 2.41, 95% confidence interval: 1.06-5.46; <i>p</i> = 0.035). After propensity score matching, 41 DAPP+ patients were matched to 82 DAPP- patients. The 2 groups did not differ in any of the baseline characteristics or safety and efficacy outcomes. DAPP is not associated with higher rates of sICH and 3-month mortality following IVT. DAPP should not be used as a reason to withhold IVT in otherwise eligible AIS candidates. This study provides Class III evidence that for IVT-treated patients with AIS, DAPP is not associated with a significantly higher risk of sICH. The study lacked the precision to exclude a potentially meaningful increase in sICH bleeding risk.