<International Circulation>: Do you agree with the routine use of cerebral protection devices to during carotid artery stenting? How can we keep the rate of neurological complications of CAS as low as possible?

Prof. Sievert: I believe so. This is a field where we do not have randomized trials but when I do a carotid stenting procedure and see some debris in the filter， even if it is just one patient out of 100， I feel it is evidence enough to continue with the use of embolic protection devices. The major issue with neurological complications is training. This has been shown in the recent publications. For example， when you look at the CREST trial (Carotid Revascularization Endarterectomy vs Stent Trial) and the ICSS trial (International Carotid Stenting Study); it appears to me that some of the operators in the ICSS trial were not that experienced and they only required 10 carotid stenting procedures before the physicians were allowed to participate in that trial. On the other hand， in the CREST trial all the physicians had to go through a lead-in phase， a training phase， and they were not allowed to enroll patients before they had done at least 20 cases plus training and additional experience. I think this made the difference and CREST was very positive and showed that stenting and surgery are equal whereas the ICSS trial was negative. Thus， I feel that training is the most important issue.