Leukocyte count predicts microembolic Doppler signals during carotid stenting - A link between inflammation and embolization

Background and Purpose - Protected stenting has emerged as a safe and effective alternative to endarterectomy for the treatment of carotid stenosis in patients at high operative risk. Distal microembolization occurs invariably during carotid stenting. Little is known about the relationship between systemic inflammation and embolization during carotid stenting. Methods - We examined 43 consecutive patients who underwent carotid stenting with simultaneous transcranial Doppler (TCD) monitoring of the ipsilateral middle cerebral artery. Embolization was quantified by measuring microembolic signals (MES) on TCD. Preprocedure leukocyte counts were related to MES. Results - In unadjusted analyses, preprocedure leukocyte count was positively correlated with total procedural MES (r(2) = 0.16; P=0.008). After considering age, gender, comorbidities, concomitant medical therapies, and the use of emboli prevention devices, increasing leukocyte count (beta=35 for each 1000/mu L increment; P=0.018) remained a significant and independent predictor of embolization (model-adjusted r(2)=0.365; P=0.0005). Conclusions - Increasing preprocedure leukocyte count independently predicted more frequent MES during carotid stenting. These data suggest that systemic inflammation may influence the degree of procedural embolization.