CAPTURE 2 Analysis Shows Influence of Site and Operator Characteristics on CAS Outcomes

February 21, 2011—William A. Gray, MD, et al conducted an analysis of the CAPTURE 2 (Carotid Acculink/Accunet [Abbott Vascular, Santa Clara, CA] Post Approval Trial to Uncover Rare Events) study for physician- or site-related variables associated with differential outcomes for carotid artery stenting (CAS). The investigators' findings were published in the Journal of the American College of Cardiology: Cardiovascular Interventions (2011;4:235–246).

As noted by the investigators, the CAPTURE 2 trial is an ongoing, prospective, nonrandomized, independently adjudicated, multicenter clinical study enrolling high-surgical-risk patients undergoing CAS.

In this assessment of CAPTURE 2, the investigators used the American Heart Association carotid endarterectomy guideline limits to define acceptable site and physician CAS outcomes; therefore, the resulting population of asymptomatic nonoctogenarian subjects in this analysis is confined to 3,388 (of the total 5,297) subjects treated at 180 hospitals in the United States by 459 operators between March 2006 and January 2009.

The investigators reported that the rate of death, stroke, and myocardial infarction was 3.5%, and the rate of death and stroke was 3.3% for the full CAPTURE 2 study cohort at 30 days. For the asymptomatic nonoctogenarian subgroup, the rates were 2.9% and 2.7%, respectively. In this subgroup, two-thirds of the sites (118 of 180; 66%) had no death or stroke events. Within the remaining sites, an inverse relationship between event rates and hospital patient volume, as well as between event rates and individual operator volume, was observed. The death and stroke rates trended lower for interventional cardiologists compared with other specialties.

The investigators concluded that outcomes from CAPTURE 2, which they note is the largest prospectively gathered, independently adjudicated, multicenter CAS study, indicate that CAS can be safely performed in a variety of hospital settings by physicians in various specialties. The most important determinant of perioperative CAS outcomes was both site and operator CAS volume. A threshold of 72 cases was found to be necessary for consistently achieving a death and stroke rate of <3% in this later-phase single-arm study; background era and nonstudy operator experience will affect this determination, advised the investigators.