Purpose: The purpose of the report was to compare contemporary outcomes of carotid endarterectomy for asymptomatic carotid stenosis with published stroke rates for best medical management.
Methods: Patients who underwent carotid endarterectomy for asymptomatic stenosis during 2005 to 2007 were identified from the National Surgical Quality Improvement Program (NSQIP) database, a risk-adjusted, outcomes-based program to measure quality of surgical care. Over the study period the number of participating hospitals varied from 121 to 283, with about half being community hospitals.
Carotid endarterectomy for asymptomatic carotid stenosis was identified by selecting cases with the Current Procedural Terminology (CPT) code for carotid endarterectomy (35301), a post-operative International Classification of Diseases 9th Revision, Clinical Modification (ICD-9-CM) diagnosis code for occlusion and stenosis of the carotid artery without mention of cerebral infarction (433.10). To eliminate potentially symptomatic cases, cases were excluded if they had an impaired sensorium, coma, hemiplegia/hemiparesis, a history of transient ischemic attack, stroke with or without residual neurologic deficit, tumor involving the central nervous system, paraplegia/paraparesis, or quadriplegia/quadriparesis. Cases were also excluded if they had disseminated cancer, emergency case classification, chemotherapy or radiotherapy within 30 days, a simultaneous surgical procedure, or previous operation within 30 days. Less clear reasons for exclusion (which may have excluded some cases with surgical complications) included open wound with or without infection, systemic sepsis within 48 hours, and contaminated/dirty wound class.
Note that the approach used was unable to ascertain the degree of preoperative carotid stenosis among cases.