Carotid revascularization treatment is shifting to low volume centers

Background: Expansion of the endovascular and surgical workforce in the USA might lead to carotid revascularization procedures being carried out at low volume centers. Objective: To evaluate trends in the treatment of carotid stenosis at high volume centers in the USA and compare outcomes by hospital volume. Methods: Using the Nationwide Inpatient Sample, we evaluated trends in the proportion of carotid revascularization procedures performed at high volume centers in the USA from 2005 to 2011. High volume was defined as combined endarterectomy/stenting volume ≥130 patients/year, carotid endarterectomy volume ≥117 cases/year and carotid stenting volume ≥38 cases/year. In-hospital mortality, discharge to a long-term facility, intracranial hemorrhage, and postoperative stroke rates were compared between high and low volume centers. Results: A total of 181 972 patients were included in this study. Overall, 63 442 patients (34.9%) were treated at high volume centers. The proportion of patients treated at high volume carotid revascularization centers decreased from 38.3% in 2005-2006 to 30.2% in 2010-2011. The proportion of patients treated at high volume centers decreased from 35.7% to 30.0% for carotid endarterectomy (p<0.0001) and 45.2% to 35.1% for carotid stenting. Patients treated at low volume centers had significantly higher rates of discharge to a long-term facility than high volume center patients (6.3% vs 5.0%, p<0.0001). The same was true for endarterectomy patients (6.0% vs 4.7%, p<0.0001) and stenting patients (8.3% vs 6.5%, p<0.0001). Conclusions: A trend toward a lower proportion of patients with carotid stenosis being treated in high volume centers from 2005 to 2011 is concerning as these high volume centers had lower complication rates.