Lesion patterns in successful and failed thrombolysis in middle cerebral artery stroke

Abstract

Thrombolysis has been shown to improve neurological recovery in acute stroke. But the response to thrombolysis is variable across patients. We sought to investigate this variability by analyzing the lesion patterns following systemic thrombolysis with recombinant tissue plasminogen activator (rtPA) and tirofiban in middle cerebral artery (MCA) stroke. One hundred three consecutive stroke patients (67 +/- 14 years) were grouped according to the site of MCA occlusion and successful or failed recanalization as assessed with magnetic resonance angiography. Infarct lesions were analyzed in T2-weighted magnetic resonance images after 10 days. Patients recovered markedly upon successful recanalization following thrombolysis (p < 0.05) but remained severely impaired when there was no recanalization within 24 h. Infarct lesions were smaller after successful than after failed recanalization (p < 0.005). They occurred throughout the cerebral cortex on the cerebral convexity in distal MCA occlusions with large individual heterogeneity. In contrast, there was a large lesion overlap in insular cortex, basal ganglia, internal capsule, and paraventricular white matter in proximal MCA occlusions. Systemic thrombolysis with rtPA and tirofiban of MCA occlusions resulted in early neurological recovery and preferentially peri-insular infarcts. In failed recanalization of the MCA stem there was a large lesion overlap in the hemispheric white matter and a lack of recovery.