Wide variation in outcomes following CAS procedures at U.S. hospitals

An analysis of a national registry found there were wide variations in care for patients undergoing carotid artery stenting (CAS) at U.S. hospitals.

Based on the researchers’ model, outcomes varied fourfold among hospitals and odds of experiencing a stroke or dying varied by 50 percent for two randomly selected hospitals treating the same patient.

Beau M. Hawkins, MD, of the University of Oklahoma Health Sciences Center in Oklahoma City, Okla., and colleagues published their findings online in the Journal of the American College of Cardiology: Cardiovascular Interventions on May 18.

They examined the National Cardiovascular Data Registry–Carotid Artery Endarterectomy and Revascularization (CARE) registry and included hospitals that contributed more than five CAS procedures from 2005 through 2013. They said the use of CAS is increasing, and providers from various medical specialties perform the procedure.

To evaluate the data, researchers used a CAS risk model to predict stroke and death in these patients. The model was derived from 11,122 procedures performed between 2005 and 2011 in the CARE registry.

For this analysis, they included 19,381 procedures from 188 hospitals. The mean unadjusted stroke or death rate was 2.4 percent, and the rates ranged from 0 percent to 18.8 percent. After adjusting for the case mix, the mean rates ranged from 1.2 percent to 4.7 percent.

The researchers divided the hospitals into three categories based on their stroke or death rates: below 0.3 percent, from 0.3 percent to 3.1 percent and greater than 3.1 percent. The corresponding annual procedural volumes per hospital were 11.3, 25.7 and 17.7.

“In our analysis, procedural volume was not found to be an important predictor of outcomes after adjustment in case mix,” they wrote. “This stands in contrast to previous reports that demonstrated an association between volume and CAS outcomes.”

They noted that CARE was a voluntary registry, so the results of this analysis may not be generalizable to all hospitals. They also mentioned they only assessed in-hospital events.