Abstract
Endovascular carotid artery stenting (CAS) is a common treatment for carotid artery stenosis and stroke prevention. Previous studies have shown that high procedural volume centers are associated with improved patient outcomes. Unplanned 30-day readmissions, which are associated with significant expenses, are increasingly used as a metric of patient outcome. Despite prior studies evaluating associations between procedural volume and multiple outcomes, the association between very high CAS volume and short-term (30-day) readmission has not yet been evaluated in a large multicenter study. The National Readmissions Database (NRD) was analyzed retrospectively from 2010 to 2015 to evaluate the association between hospital procedural volume and patient outcomes in asymptomatic and symptomatic CAS patients. Very high volume centers (VHVC) were defined as the top 10% hospitals in terms of procedural volume, performing >= 79 procedures a year. Univariate and multivariate analyses of patient and hospital characteristics evaluated associations with short-term (30-day) readmissions (SR), long-term (90-day) readmissions (LR), index mortality, discharge disposition, major complications, and neurological complications. A total of 36,128 asymptomatic patients and 8,390 symptomatic patients who underwent CAS were identified. Asymptomatic CAS patients treated at VHVCs were associated with decreased likelihood of SR (OR 0.88, 95% CI 0.80-0.95, p = 0.003) and LR (OR 0.91, 95% CI 0.85-0.99, p = 0.037) compared to asymptomatic patients at non-VHVCs. There was no significant difference in SR or LR between symptomatic CAS patients treated at a VHVC vs. non-VHVC. Our findings provide additional evidence to support the role of experience in improved CAS treatment outcomes.