Abstract 2684: Clopidogrel Load For Emboli Reduction In Patients With Symptomatic Carotid Artery Stenosis Undergoing Urgent Carotid Endarterectomy (CEA): A Multicenter Pilot Feasibility Study

Abstract

Background&Purpose: Microembolic signals (MES) on transcranial Doppler (TCD) are an independent risk factor for recurrent stroke and neurological deterioration in patients with extracranial symptomatic and asymptomatic carotid artery disease (CARAD). Clopidogrel load (300mg) combined with dual antiplatelet therapy has been shown to reduce asymptomatic embolization in patients with symptomatic CARAD. We sought to determine feasibility of clopidogrel load in decreasing asymptomatic embolization in patients with symptomatic CARAD undergoing urgent CEA within the first 8 days from the index event. Subjects&Methods: Consecutive patients with symptomatic CARAD (70%-99% stenosis) and presence of MES on 1-hour baseline (<24 hours from the index event) TCD-monitoring of ipsilateral middle cerebral artery (MCA) were treated with clopidogrel load followed by clopidogrel 75mg±aspirin 100mg during the elapsed time period between hospital admission and urgent CEA at three tertiary care stroke centers. Repeat 1-hour TCD monitoring was performed the day before surgery. Bleeding complications during surgery and recurrent strokes/TIAs during the first month following the index event were prospectively documented. Functional independence at three months was evaluated using the modified Rankin Scale (mRS) Score. Results: A total of 9 symptomatic CARAD patients (mean age 66±6years, 89% men, 56% ischemic strokes, median NIHSS 4 points, interquartile range 0-8, 44% TIAs) were treated with clopidogrel load followed by dual (66%) or single (33%) antiplatelet therapy. MES count was significantly reduced between baseline (<24 hours from index event, median count 8 MES/hr, interquartile range 6-17) and repeat (4-7 days from index event, median count 0 MES/hr, interquartile range 0-4; p=0.008 by Wilcoxon Signed Ranks Test) TCD-monitoring. The mean MES frequency reduction (compared to baseline) was 89% (95%CI:77%-100%). No bleeding complications (0%) or recurrent strokes (0%) were documented. All patients were functionally independent (mRS-scores of 0-1) at three months. Conclusions: Our pilot study shows feasibility of administering clopidogrel load followed by dual or single antiplatelet therapy to reduce asymptomatic embolization in patients with symptomatic CARAD who are scheduled to undergo urgent CEA. The present findings are subject of a larger ongoing multi-center study.