Abstract W MP97: Trends in Volume and Mortality in CEA after Introduction of CAS in Medicare population
Background: Inverse relationship between outcome and physician volume for carotid endarterectomy (CEA) has been previously established. Following the 2005 National Coverage Determination which reimburses carotid artery stenting (CAS) for Medicare beneficiaries, the number of CAS procedures increased and the number of CEA declined. We hypothesized that the reduced number of CEA procedures resulted in lower case volumes for surgeons, adversely affecting patients' peri-procedural outcomes.
Methods: We identified inpatient CEA procedures and performing surgeons in the Medicare claims files 2001-2008. We calculated surgeon volume as the number of CEAs performed in the past 365 days and categorized volume as very low (<5), low (5-9), medium (10-29) and high (≥30). Yearly trend of: 1) rate of CEA procedures, 2) proportion of CEAs performed by categories of surgeon volume , 3) patient characteristics , and 4) 30-day mortality overall and by categories of surgeon volume, were analyzed.
Results: We identified 450,727 Medicare beneficiaries undergoing CEAs. The rate of CEA procedures per 10,000 beneficiaries declined consistently after 2002, resulting in decrease in the proportion of procedures performed by high volume surgeons (from 46% in 2002 to 33% in 2008). Patients selected for CEA became older and increased in the proportion of patients with atrial fibrillation, COPD, and chronic kidney disease, but decreased in the proportions with prior myocardial infarction and concurrent CABG. Thirty day mortality improved consistently over the years from 1.41% (95% confidence interval: 1.35-1.48) in 2001-2002 to 1.18% (1.12-1.25) in 2007-2008. This trend persisted after adjustment for patient characteristics, and in all volume categories.
Conclusion: The rate of CEA procedures decreased substantially between 2001-2008 as have performing surgeon case volumes . Dissemination of CAS has not adversely impacted the peri-procedural mortality of CEA Medicare patients.
Author Disclosures: H. Kumamaru: None. J.J. Jalbert: None. L.L. Nguyen: None. J. Liu: None. M.D. Gerhard-Herman: None. C. Chen: None. L.A. Williams: None. J.D. Seeger: Consultant/Advisory Board; Significant; Optum Insight, WHISCON. S. Setoguchi: Research Grant; Significant; Johnson &Johnson.
- © 2014 by American Heart Association, Inc.