Increased National In-Hospital Mortality Following Carotid Stenting As Compared To Carotid Endartrectomy

James T McPhee¹, Josh Hill¹, Mohammad H Eslami¹, John Blebea², Rocco G Ciocca¹, Louis M Messina.¹.
¹University of Massachusetts, Worcester, MA;²Temple University Medical School, Philadelphia, PA.

OBJECTIVES: Although carotid endarterectomy (CEA) is the gold standard for the treatment of carotid artery stenosis, the recent FDA approval of carotid artery stenting (CAS) has led to its increased use outside of clinical trials and registries. The objective of this study was to compare mortality rates between CAS and CEA at the national level, outside of clinical trials, and to examine what factors affect such mortality.

METHODS: The Nationwide Inpatient Sample queried to identify all patient-discharges that occurred for revascularization of carotid artery stenosis. The ICD9 CM diagnostic codes for carotid artery stenosis, with (433.11) and without (433.10) stroke, were used in conjunction with the procedural codes for CEA (38.12) and CAS (39.50; 39.90; 0.63). Primary outcome measure was in-hospital mortality. Rao-Scott chi-square was used for univariate analysis of relevant variables. Multivariable logistic regression was done to evaluate in-hospital mortality with adjustment made for age, sex, medical comorbidities, admission diagnosis, procedure type, year, and hospital type.

RESULTS: During 2003-2004, there were 217, 468 patient discharges following revascularization for carotid artery stenosis. The majority of revascularization procedures, 97%, were in patients without a diagnosis of stroke. Results are partially summarized in Table 1. By logistic regression analysis, controlling for diagnosis type and medical comorbidities, endovascular treatment was independently predictive of increased in-hospital mortality as compared to CEA (O.R. 2.66; 95% C.I. 1.63-4.34). Other significant factors included the diagnosis of stroke and the presence of congestive heart or renal failure but gender or hospital type (teaching vs. non-teaching) did not affect mortality rates. The mean length of stay was 2.5 days for both groups.

CONCLUSIONS: Based on a large representative national sample, carotid stenting has significantly increased in-hospital mortality as compared to CEA. This difference is most pronounced in patients treated following stroke. These results, observed outside of clinical trials and registries, indicate a higher mortality rate for CAS in clinical practice as compared to surgical revascularization.