From the Society for Clinical Vascular Surgery
An analysis of carotid artery stenting procedures
performed in New York and Florida (2005-2006):
Procedure indication, stroke rate, and mortality
rate are equivalent for vascular surgeons and non-
Robert Steppacher, MD, Nicholas Csikesz, BS, Mohammad Eslami, MD, Elias Arous, MD,
Louis Messina, MD, and Andres Schanzer, MD,Worcester, Mass
Objective: Carotid artery stenting (CAS) has emerged as an alternative to carotid endarterectomy (CEA) for the treatment
of carotid artery stenosis. Unlike CEA, CAS is performed by a wide variety of specialists including vascular surgeons (VS),
interventional cardiologists (IC), and interventional radiologists (IR). This study compares the indications, in-patient
mortality rate, and in-patient stroke rate for patients undergoing CAS, according to operator specialty.
Methods: The State In-patient Databases from New York and Florida, made available by the Healthcare Cost and
Utilization Project, were reviewed by International Classification of Disease (ICD)-9-CM codes to identify all patients
treated with CAS for the years 2005 and 2006. This cohort was then stratified according to operator specialty defined by
procedures performed by each operator over the years surveyed. Primary endpoints were in-patient death and stroke.
Propensity score matching adjusting for indication, demographics, and comorbidities was employed to evaluate the
influence of operator type on outcomes.
Results: During the study period, 4001 CAS procedures were performed. All primary analyses compared VS (n ? 1350)
to non-VS (n ? 2651). Patient characteristics were similar, except VS treated fewer patients with CAD (44.2% vs 50.9%,
P < .001) and valvular disease (6.3% vs 8.6%, P ? .01) and more patients with chronic lung disease (19.4% vs 15.9%,
P ? .01). Each group performed an equal proportion of CAS for symptomatic disease (8.1% vs 9.0%, P ? .32). Univariate
analysis revealed no difference in mortality (0.9% vs 0.5%, P ? .13) or stroke (1.3% vs 1.5%, P ? .73). Propensity score
matched analysis also demonstrated no difference in mortality (0.7% vs 0.4%, P ? .48) or stroke (1.1% vs 1.7%, P ? .27).
Subgroup analysis comparing VS, IC, and IR showed no significant difference in mortality or stroke, but demonstrated
that of the three specialties, IC treated the smallest proportion of symptomatic patients. The proportion of CAS
performed by VS differed significantly by state (New York 46%, Florida 19%, P < .01).
Conclusion: Despite a paucity of level 1 evidence for CAS in asymptomatic patients and current Centers for Medicare and
Medicaid Services (CMS) policy limiting reimbursement for CAS to only high-risk symptomatic patients, VS and non-VS
are treating primarily asymptomatic patients. Perioperative rates of stroke and death are equivalent between VS, IC, and
IR. Regional variation of operator type is substantial, and despite similar outcomes, <50% of CAS is performed by VS.
(J Vasc Surg 2009;49:1379-86.)
Since its inception in the early 1990s, carotid artery
stenting (CAS) has emerged as an alternative to carotid
endarterectomy (CEA) for the treatment of carotid artery
occlusive disease. Numerous single institution studies,1
stent registry reports,2,3administrative dataset evalua-
tions,4-6and randomized controlled trials,7-9have assessed
the safety and efficacy of CAS for the treatment of both
symptomatic and asymptomatic carotid artery disease.10
Because the results of these studies have been mixed, CEA,
founded on a history of rigorous evidence-based valida-
CAS use has continued to increase dramatically.3
In contrast to CEA, which has been performed uni-
formly by surgeons (primarily those trained specifically in
vascular surgery), CAS has been embraced by multiple
specialty groups that possess catheter and guidewire skills.
Accordingly, professional societies of vascular surgeons,13
cardiologists,14and interventional radiologists15have is-
of this technology and credentialing requirements for pro-
viders performing CAS. Despite the increasing rate of CAS
procedures being performed by these different operators,
the current role of CAS remains undefined. This sentiment
was reinforced by the Centers for Medicare and Medicaid’s
recent decision to deny reimbursement for CAS in any
From the Division of Vascular and Endovascular Surgery, University of
Massachusetts Medical School.
Competition of interest: none.
Presented at the 2009 Society for Clinical Vascular Surgery, March 18-21,
2009, Fort Lauderdale, Fla.
Reprint requests: Andres Schanzer, MD, Division of Vascular and Endovas-
cular Surgery, University of Massachusetts Memorial Medical Center,
55 Lake Avenue North, Worcester, MA 01655 (e-mail: schanzea@
Copyright © 2009 by the Society for Vascular Surgery.
ment success. The rigorous patient de-identification pro-
cess employed by the State Inpatient Databases to protect
clinical data. Therefore, it was impossible to evaluate other
equally important outcomes, such as long-term morbidity
and mortality or restenosis.
Despite a paucity of evidence in support of performing
CAS in asymptomatic patients and current CMS guidelines
reimbursing CAS for only high-risk symptomatic patients,
both VS and non-VS are treating primarily asymptomatic
patients. Perioperative rates of stroke and death are equiv-
alent between VS, IC, and IR. Regional variation is sub-
stantial, and despite similar outcomes, fewer than 50% of
CAS procedures are performed by VS.
Conception and design: RS, AS
Analysis and interpretation: RS, NC, AS
Data collection: RS, NC, AS
Writing the article: RS, NC, AS
Critical revision of the article: RS, ME, EA, LM, AS
Final approval of the article: RS, NC, ME, EA, LM, AS
Statistical analysis: RS, NC, AS
Obtained funding: AS
Overall responsibility: AS
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Submitted Jan 5, 2009; accepted Feb 11, 2009.
William C. Mackey, MD, Boston, Mass
This study, based on an administrative database of ?4000
carotid stent procedures, has three major findings: (1) 91%
of carotid stents are performed in asymptomatic patients, (2)
there is significant regional variation in who is performing
carotid stents (46% by vascular surgeons in New York and only
19% by vascular surgeons in Florida), and (3) early outcomes
across the three specialties performing carotid stenting are
JOURNAL OF VASCULAR SURGERY
Volume 49, Number 6