Abstract WP106: Timing of Tissue-plasminogen-activator Induced Recanalization and Functional Recovery in Acute Ischemic Stroke

Abstract

Introduction: Although onset-to-treatment time is associated with early clinical recovery in acute ischemic stroke (AIS) patients treated with intravenous tissue plasminogen activator (tPA), the effect of the timing of tPA-induced recanalization on functional outcomes in AIS remains debatable. Methods: We sought to determine whether early (within 1-hour from tPA-bolus) complete or partial recanalization assessed during 2-hour real-time transcranial Doppler (TCD) monitoring is independently associated with improved 3-month outcomes in tPA-eligible patients with proximal intracranial arterial occlusions. Outcome events included dramatic clinical recovery (DCR) within 2 and 24-hours from tPA-bolus, 3-month mortality, favorable functional outcome (FFO) and functional independence (FI) defined as modified Rankin Scale scores of 0-1 and 0-2 respectively. Results: We prospectively enrolled 480 AIS patients (mean age 66±15 years, 60% men, baseline NIHSS score 15) during a 7-year period from 12 participating centers. Complete or partial early recanalization was detected in 53% of patients. Patients with early recanalization had (p<0.001) higher rates of 2-hour DCR (54% vs. 10%), 3-month FFO (67% vs. 28%), FI (81% vs. 39%) and lower mortality rates (6% vs. 17%) compared to patients with persisting occlusions. In multivariable analyses, recanalization during tPA infusion was independently (p<0.05) associated with higher probability of three-month FFO and lower likelihood of three-month mortality. Onset to treatment time correlated to the elapsed time between tPA-bolus and recanalization (Spearman’s rho= +0.151, p=0.009). Conclusions: Earlier tPA treatment after stroke onset is associated with faster tPA-induced recanalization. Earlier onset-to-recanalization time results in improved functional recovery and survival in AIS patients with proximal intracranial occlusions.