Complication Rates and Center Enrollment Volume in the Carotid Revascularization Endarterectomy Versus Stenting Trial

Study Questions:

What was the effect of enrollment volume by site on complication rates in the CREST (Carotid Revascularization Endarterectomy Versus Stenting Trial) study?


The authors assessed the impact of site enrollment volume on outcome among patients enrolled in the CREST trial. The primary composite endpoint was any stroke, myocardial infarction, or death within 30 days or ipsilateral stroke in follow-up. The study required that the participating surgeons must have performed >12 procedures per year with complication rates <3% for asymptomatic patients and <5% for symptomatic patients and the interventionists were certified after a rigorous two-step credentialing process. CREST centers were divided into tertiles based on the number of patients enrolled into the study, with Group 1 sites enrolling <25 patients, Group 2 sites enrolling 25-51 patients, and Group 3 sites enrolling >51 patients.


Low-volume enrolling sites were more likely to enroll patients who were older and symptomatic. The safety of carotid angioplasty and stenting and carotid endarterectomy did not vary by site-volume during the periprocedural period, as indicated by occurrence of the primary endpoint (p = 0.54) or by stroke and death (p = 0.87).


The authors concluded that complication rates were low in CREST and were not associated with center enrollment volume.


There is a fairly large body of data demonstrating an association between operator (or institutional) volume and outcome after surgical procedures. The results of this study suggest that the number of patients enrolled in the CREST trial was not correlated with outcome for either carotid surgery or stenting. The findings are not surprising since the study did not truly evaluate overall operator or institutional experience, and the rigorous selection process would have screened out institutions and operators with poor outcomes. However, it does demonstrate that in carefully selected centers and with a well-defined operator selection process, both carotid stenting and endarterectomy can be performed with remarkable safety.

Clinical Topics: Invasive Cardiovascular Angiography and Intervention

Keywords: Myocardial Infarction, Stroke, Credentialing, Endarterectomy, Carotid, Angioplasty, Stents

< Back to Listings