Comparative Evaluation of Angioscopy and Intravascular Ultrasound for Assessing Plaque Protrusion During Carotid Artery Stenting Procedures.

BACKGROUND:Evaluation of plaque protrusion after carotid artery stenting (CAS) is important for predicting periprocedural ischemic complications. In contrast to intravascular ultrasound (IVUS), angioscopy allows direct visualization of the plaque. The aim of this study was to evaluate utility and safety of angioscopy during CAS and compare it with IVUS. METHODS:The study included 13 carotid artery stenosis lesions in 11 consecutive patients (mean age 70.5 years; 10 men) at a single center. During CAS procedure, poststenting plaque protrusion was evaluated with angioscopy and IVUS. RESULTS:Mean level of internal carotid artery stenosis was 79.2%. Eight lesions were symptomatic, and 5 lesions were predicted to have vulnerable plaque by preprocedural magnetic resonance imaging. A carotid WALLSTENT was placed in all cases. After stenting, angioscopy provided good visualization in all cases. Plaque protrusions were observed in 1 case by IVUS and in 8 cases by angioscopy. Diffusion-weighted imaging showed positive lesions in 3 cases (23%). For 2 of these lesions, plaque protrusions were observed by angioscopy but not by IVUS. All lesions associated with positive diffusion-weighted imaging findings were observed to have yellow plaque on angioscopy. CONCLUSIONS:Angioscopy provided direct visualization of stent lumens after CAS. Angioscopy detected more plaque protrusion than IVUS and allowed clearer observation of plaque characteristics. Angioscopy may be more useful than IVUS for examination of plaque protrusion and plaque evaluation after CAS, especially for plaque identified as potentially vulnerable by preprocedural examination.