New embolic protection devices: a review

The use of embolic protection (EPD) during carotid artery stenting (CAS) has always made intuitive sense. There is no randomized trial evidence in favour of the use of EPDs and this results from the statistical challenge posed when attempting to compare variations in technique based on the outcome measure all stroke/death/myocardial infarction (MI) for a procedure such as CAS which, in experienced units, is associated with such a low baseline hazard. In order to detect a statistically meaningful difference between protected and unprotected populations, many thousands of patents would have to be recruited and this would entail a concerted effort amongst a population of physicians who are largely beyond uncertainty or equipoise regarding this particular issue. Accepting this, each type of device has been shown to capture macroemboli, implying, irrefutably, an added level of protection for the brain during CAS when EPDs are employed. Since their inception early in the last decade, the stenting community has been aware of the limitations of each type of system and accordingly, necessity has driven invention. This review seeks to present data on the newest EPDs, the philosophy behind them, their unique advantages, clinical data supporting their use and data highlighting the influence of these newer systems on the microembolic penalty of CAS, where available.