The Efficacy of IV Tissue Plasminogen Activator for Restoring Cerebral Blood Flow in the Hours Immediately after Administration in Patients with Acute Stroke

BACKGROUND AND PURPOSE: Timely restoration of tissue-level cerebral blood flow is the goal of thrombolytic therapy in patients presenting with an acute ischemic stroke. We aimed to identify the incidence and predictors of reperfusion immediately following treatment with intravenous recombinant tissue plasminogen activator (IV rt-PA). METHODS: This study included patients with acute ischemic stroke triaged using magnetic resonance imaging (MRI) with perfusion-weighted imaging (PWI) and treated with IV rt-PA who were subsequently enrolled in our natural history study and underwent repeat MRI with PWI approximately 2 hours posttreatment. Early reperfusion was defined as >80% decrease in the size of initial perfusion deficit on the 2 hours follow-up MRI. Demographics, stroke risk factors, presenting National Institutes of Health Stroke Scale score, and location of the thrombosis were compared between patients with and without early reperfusion. RESULTS: Of the 49 patients included in this study, 21 (43%) had early reperfusion. The mean age for patients with early reperfusion was significantly lower in comparison to the patients without early reperfusion (64 vs. 76, P =.01). The prevalence of hyperlipidemia was significantly lower among patients with early reperfusion (24% vs. 54%, P =.036). Patients with early reperfusion were less likely to have large-vessel occlusion (LVO) (internal carotid artery terminus or proximal middle cerebral artery) (24% vs. 50%, P =.06). In a multivariate analysis, the presence of an LVO was an independent predictor of lack of early reperfusion (OR [95%Cl]:.13 [.019-.89], P =.038). CONCLUSION: Early reperfusion was found in a substantial percentage of the patients treated with IV rt-PA. It was more common in patients without LVO.