Pretreatment with the Free Radical Scavenger Edaravone Prevents Cerebral Hyperperfusion after Carotid Endarterectomy

Abstract

Abstract OBJECTIVE: Cerebral hyperperfusion syndrome after carotid endarterectomy (CEA) is a rare but potentially devastating complication. The purpose of the present study, which was not a randomized controlled trial but a case cohort study with historical control, was to determine whether pretreatment with a novel free radical scavenger, edaravone, could prevent occurrence of cerebral hyperperfusion after CEA. METHODS: Fifty patients with ipsilateral internal carotid artery stenosis (≥70%) underwent CEA with administration of edaravone before internal carotid artery clamping. Preoperative cerebral blood flow and cerebrovascular reactivity (CVR) to acetazolamide were assessed with single-photon emission computed tomography (SPECT). Cerebral blood flow also was measured immediately after CEA and on the 3rd postoperative day. RESULTS: Cerebral hyperperfusion (cerebral blood flow increase ≥100% compared with preoperative values) was revealed by SPECT performed immediately after CEA in only one patient (2%), who also exhibited reduced preoperative CVR. The incidence of post-CEA hyperperfusion as revealed by SPECT in the control group (51 CEA patients without administration of edaravone) was significantly higher (16%) (P= 0.0310, control versus treatment group). In addition, in a subgroup of patients with reduced preoperative CVR, the incidence of post-CEA hyperperfusion as revealed by SPECT in the edaravone group (7%) was significantly lower than that in the control group (67%) (P= 0.0029). Logistic regression analysis demonstrated that reduced preoperative CVR and absence of pretreatment with edaravone were significant independent predictors of post-CEA hyperperfusion as revealed by SPECT. CONCLUSION: Pretreatment with edaravone can prevent occurrence of cerebral hyperperfusion after CEA.