Intracranial hemorrhage after carotid endarterectomy and carotid stenting in the United States in 2005

Abstract

Background: Intracranial hemorrhage (ICH) following carotid endarterectomy (CEA) or carotid artery stenting (CAS) is a rare but potentially devastating complication. The effect of more intense dual antiplatelet therapy required for CAS on the frequency of ICH has not been established. This study was undertaken to evaluate the nationwide occurrence of ICH associated with CAS vs CEA.

Methods: The Nationwide Inpatient Sample was used to identify patients discharged after CAS and CEA during 2005. The type of revascularization and major adverse events, ie, in-hospital ICH, postprocedural stroke, and death rates, were determined by cross-tabulating specific procedural codes for CAS and CEA and diagnostic codes for carotid stenosis. Risk stratification was performed using the Charlson Comorbidity Index. Univariate and multivariate logistic regression analyses were used to assess the association between type of revascularization, comorbidities, ICH, and risk-adjusted mortality.

Results: In 2005, the estimated number of carotid revascularizations was 135,903. The vast majority of patients underwent CEA (90.4%), whereas CAS was performed in 13,093 (9.6%) patients. Most patients (92.2%) underwent treatment for asymptomatic carotid stenosis. CAS patients had higher postoperative stroke rates (2.1% vs 1.1%; P < .001) and in-hospital mortality (1.1% vs 0.6%; P < .001) than CEA patients. ICH occurred in 19 patients (0.15%) after CAS and in 20 patients (0.016%) after CEA (P < .001). CAS was identified as an independent predictor for postoperative stroke (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.5-2.0; P < .001), in-hospital mortality (OR, 1.49; 95% CI, 1.2-1.8; P < .001) and ICH (OR, 5.9; 95% CI, 3.1-11.1; P < .001) after adjusting for age, gender, symptomatic status, comorbidities, admission, and hospital type using logistic regression. In-hospital mortality was 12.5% among patients developing ICH (OR, 23.2; 95% CI, 9.1-54.4; P < .001).

Conclusion: In the United States, patients undergoing CAS have not only significantly increased postoperative stroke and death rates compared with those undergoing CEA, but also a sixfold increased risk of ICH. Although ICH after CAS is extremely rare, its devastating nature and high mortality warrant further investigation to define specific risk factors, prevention, and treatment strategies.