Abstract TP523: A Randomized Controlled Trial Evaluating the Effectiveness of Pretreatment With the Free Radical Scavenger, Edaravone, Before Carotid Artery Stenting

Objective: Cerebral hyperperfusion syndrome (CHS) is likely to occur after carotid revascularization in patients with severe hemodynamic failure. It is important to control cerebral hyperperfusion phenomenon (CHP) to prevent the development of CHS. To determine whether pretreatment with the free radical scavenger, edaravone, could prevent the onset of CHP after carotid artery stenting (CAS). Methods: Patients with severe carotid artery stenosis were randomized to receive either pretreatment with edaravone immediately before CAS or the common CAS procedure. Cerebral blood flow (CBF) was assessed in the affected middle cerebral artery (MCA) region and in the ipsilateral cerebellum using single-photon emission computed tomography (SPECT) of the brain before and immediately after CAS. Cerebrovascular reactivity (CVR) in the MCA region was also evaluated using the stereotactic extraction estimation based on the Japanese extracranial-intracranial bypass trial (SEE-JET) program and classified as reduced when it was <18.4%. The ratio of MCA to cerebellar activity was defined as the CBF in the affected MCA region divided by the CBF in the ipsilateral cerebellar hemisphere. CHP was defined as an increase in the ratio of MCA to cerebellar activity after CAS ≥10%. Results: Of the 52 patients recruited in this study, 26 were assigned to the pretreatment with edaravone group and 26 were assigned to the treatment as the usual group. Eleven patients showed reduced CVR. CHP occurred in 0 of 6 patients in the edaravone group and in 4 of 5 patients in the usual group (0% vs. 80%, p=0.0152). However, there was no significant difference in the overall patient population between the two groups. Conclusion: Pretreatment with edaravone could reduce the incidence of CHP after CAS in patients with reduced CVR.