Pretreatment with the free radical scavenger edaravone prevents cerebral hyperperfusion after carotid endarterectomy

OBJECTIVE: Cerebral hyperperfu'sion syndrome after carotids endarterectomy (CEA) isa 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 (greater than or equal to70%) 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 ASPECT). Cerebral. blood flow also was measured immediately after CEA and on the 3rd postoperative day. RESULTS: Cerebral, hyperperfusion (cerebral blood flow increase greater than or equal to100% 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.