ABSTRACT
Despite advanced stenting techniques, clinical neurological events may complicate carotid angioplasty and stenting (CAS) procedures.1-3 Obstructive carotid artery lesions are known to contain friable thrombotic and atherosclerotic components that can embolize during the carotid intervention and are responsible for the majority of the associated neurological complications.4,5 Efforts are ongoing to optimize the outcome of this treatment by identifying clinical and/or angiographic factors that predispose to these events, and by developing strategies using ‘antiemboli devices’ that capture the released embolic matter before it reaches the brain, thus minimizing the risk of embolic events.4 Detection and quantification of the embolic material during CAS and the immediate postprocedural period would improve patient selection for this treatment and facilitate the refinement of the antiembolic strategies. Live In vivo detection of microemboli passing through the
cerebral circulation can be achieved using transcranial Doppler (TCD).6-8 This technique is highly sensitive and specific, and provides a quantitative tool for microembolization in a variety of clinical settings. Microemboli produce unique and characteristic Doppler signals [microembolic signals (MES)] that are very specific when strict recognition criteria are applied (Fig. 11.1).6 Although the Doppler-detected microemboli are microscopic in size and clinically silent, their ability to predict embolic neurological events has been demonstrated in a variety of clinical conditions, such as carotid endarterectomy (CEA), atrial fibrillation and coronary bypass surgery.7 This chapter discusses the application of TCD monitoring for microemboli during CAS and the clinical implications of the currently available data.
