Predictive Factors for Early Clinical Improvement after Intra-arterial Thrombolytic Therapy in Acute Ischemic Stroke

Abstract

In acute ischemic stroke, the speed of improvement after intra-arterial thrombolytic therapy (IAT)-mediated recanalization varies. This study aimed to identify clinical and radiological variables that are predictive of early improvement (EI) after IAT in acute ischemic stroke. This single-center retrospective cohort study included 141 consecutive patients who underwent IAT for terminal internal carotid and/or middle cerebral artery (MCA) occlusions. EI was defined as a National Institutes of Health Stroke Scale (NIHSS) score less than 3 or NIHSS score improvement of 8 points or more within 72 hours of IAT. The EI and non-EI groups were compared in terms of clinical and radiological findings before and after IAT. Forty-nine patients showed EI (34.8%). Multivariate analysis revealed that atrial fibrillation (odds ratio [OR] .35, 95% confidence interval [CI] .14-.89, P = .028) and hyperdense MCA sign (OR .39, CI .15-.97, P = .042) were related with lack of EI. The independent EI predictors were less extensive parenchymal lesion on baseline computed tomography (OR 4.92, CI 1.74-13.9, P = .003), intermediate to good collaterals (OR 3.28, CI 1.16-9.31, P = .026), and recanalization within 6 hours of symptom onset (OR 5.2, CI 1.81-14.94, P = .002). EI associated with favorable outcomes (modified Rankin scale score 0-2) at discharge (88% versus 7%; P < .001) and 3 months after discharge (92% versus 18%; P < .001). The clinical and radiological variables maybe useful for predicting EI and favorable long-term outcomes after IAT.