Clopidogrel load for emboli reduction in patients with symptomatic carotid stenosis undergoing urgent carotid endarterectomy.

BACKGROUND AND PURPOSE Microembolic signals (MES) on transcranial Doppler are an independent risk factor for recurrent stroke in patients with extracranial symptomatic/asymptomatic carotid artery stenosis (CARAS). Clopidogrel load (300 mg) combined with dual antiplatelet therapy has been shown to reduce MES in patients with symptomatic CARAS. We sought to determine feasibility of clopidogrel load in decreasing asymptomatic embolization in patients with symptomatic CARAS undergoing urgent carotid endarterectomy within the first 2 weeks from the index event. Subjects and METHODS Consecutive patients with symptomatic CARAS (70%-99%) and presence of MES on 1-hour baseline (<24 hours from the index event) transcranial Doppler monitoring of ipsilateral middle cerebral artery were treated with clopidogrel load followed by clopidogrel (75 mg)±aspirin (100 mg) during the elapsed time period between hospital admission and urgent carotid endarterectomy at 3 tertiary-care stroke centers. Repeat 1-hour transcranial Doppler monitoring was performed the day before surgery. Bleeding complications during surgery and recurrent strokes or transient ischemic attacks during the first month of ictus were prospectively recorded. RESULTS A total of 11 symptomatic CARAS patients (mean age, 66±7 years; 73% men; 64% acute ischemic strokes) were treated with clopidogrel load followed by dual (67%) or single (33%) antiplatelet therapy. MES count was significantly reduced between baseline (median count, 8 MES/h; interquartile range, 6-19) and repeat transcranial Doppler monitoring (0 MES/h; interquartile range, 0-3; P=0.003). No bleeding complications, recurrent strokes, or transient ischemic attacks were documented. CONCLUSIONS Our pilot observational study provides preliminary nonrandomized data regarding the potential efficacy of clopidogrel load to reduce asymptomatic embolization in patients with symptomatic CARAS before urgent carotid endarterectomy.