Timing of complications during carotid artery stenting. How can they be predicted?

Carotid artery stenting (CAS) is becoming increasingly common for the treatment of carotid stenosis. Accumulating data, but not randomised data, suggest that CAS has promising efficacy in preventing stroke with an acceptable rate of procedure-related complications when compared to carotid endarterectomy (CEA). However, CAS procedures can carry a risk of non-negligible complications such as cerebral embolization, cerebral hemorrhage, severe hypotension and bradycardia. These may occur after the first 24 hours. Lessons may be learned from the timing of occurrence of CAS adverse events. The most severe neurological complications are generally due to embolism and occur intraprocedurally especially during catheter, wire or sheath manipulation in the aortic arch and common carotid. These strokes, obviously, cannot be prevented by using cerebral protection devices and enhance the importance of an appropriate learning curve that includes proper material choice, patient selection, good technique and the skill of "know when to quit".