Carotid artery stenting: effect of learning curve and intermediate-term morphological outcome

To assess the impact of learning on the rate of success and complications of carotid stenting in a single-center, one-operator series and prospectively follow a patient cohort with regard to restenosis.

In 303 patients (mean age 70 +/- 8.8 years), 320 internal carotid arteries (ICA) were treated with carotid stenting for stenoses > or = 70%. Four groups of 80 consecutive interventions were compared with regard to primary technical success and periprocedural complications. Stent patency in follow-up was assessed using duplex scanning.

Stenting was successful in 298 (93%) arteries. The combined neurological complications (transient ischemic attacks and all strokes) and 30-day death rate was 8.2% (n = 25), but the all stroke and 30-day death rate was 3.0% (n = 9). A significant reduction in the frequency of neurological complications after the initial 80 interventions was observed (p = 0.03), but technical success was not appreciably improved with increasing experience thereafter. Over a median 12 months (interquartile range 6 to 24), cumulative patency rates were 91%, 90%, and 91% at 6, 12, and 36 months, respectively.

Elective carotid stenting can be performed with excellent technical success, an acceptable frequency of periprocedural complications, and good intermediate-term patency. However, our findings suggest that a larger number of interventions should be performed to overcome the negative effects of the initial learning phase.