Embolic Protection Devices in Transcatheter Aortic Valve Replacement.

The initially reported periprocedural neurological events rates associated with transcatheter aortic valve replacement raised concerns that ultimately led to the development and to the clinical research of novel embolic protection devices. Although the reduction of clinical stroke is a desired goal, the current research design of embolic protection devices focuses on surrogate markers of the clinical disease, primarily on silent central nervous system lesions observed in postprocedural diffuse-weighted magnetic resonance imaging and cognitive function testing. As the mere presence of particulate debris in brain matter may not correlate with the extent of brain injury, cognitive function, or quality of life, the clinical significance of embolic protection devices has yet to be determined, and interpretation of study results with regard to real-life clinical use should be viewed accordingly. The purpose of this article is to provide an overview of the updated ongoing clinical research on embolic protection devices and present its major caveats.