From the Southern Association for Vascular Surgery
Atrial fibrillation is associated with increased
risk of perioperative stroke and death from
Nancy L. Harthun, MD,aand George J. Stukenborg, PhD,bCharlottesville, Va
Background: Carotid endarterectomy is performed in high volume in the United States. Identifying patients with a higher
risk of stroke and death after carotid endarterectomy can lead to modifications in care that would significantly reduce the
occurrence of these events. This study evaluates whether atrial fibrillation is significantly associated with an increased risk
of death or stroke for patients undergoing carotid endarterectomy.
Methods: This retrospective cohort study uses multivariable logistic regression analysis to assess the relationship between
atrial fibrillation and death and/or stroke after carotid endarterectomy. The study population is drawn from the National
Inpatient Sample, 2005. All patients with a primary carotid endarterectomy and diagnosis of stenosis of precerebral
arteries were included, except patients with concomitant open heart procedures. The main outcomes examined were
in-hospital death and stroke, adjusted for age, gender, symptomatic status, and for comorbid disease.
Results: Carotid endarterectomy was performed for 20,022 patients. Strokes occurred in 189 patients (0.94%), and death
occurred in 59 (0.29%). Patients with atrial fibrillation had significantly higher adjusted odds of stroke or death (odds
ratio ? 2.45; P < .0001).
Conclusion: Patients with atrial fibrillation have a substantially higher risk of stroke and death after carotid endarterec-
tomy. (J Vasc Surg 2010;51:330-6.)
Carotid endarterectomy (CEA) is performed to lower
the risk of stroke among patients considered to be at risk
from carotid artery stenosis. Ironically, perioperative stroke
is one of the most common major complications of this
procedure. Approximately 100,000 CEAs are performed
annually in the United States.1Adverse events are rare. The
percentage of patients who experience a stroke during the
perioperative period is between 0.7 to 1.5, and the percent-
age of perioperative death is approximately 0.5.2However,
because of the high volume, CEA is responsible for 1000
strokes or deaths per year. Decreasing the adverse event
rates for this high volume procedure can meaningfully
improve patient outcomes in the population. The first step
in lowering this event rate would be to identify which
patients are at higher risk of stroke or death as a complica-
tion of the procedure.
There is little guidance available regarding which co-
morbid illnesses are potential contraindications for CEA,
and the identification of specific comorbid illness or com-
binations of comorbid illnesses that generate higher risk of
major adverse events after CEA has not been determined in
any systematic fashion. This type of determination is sub-
ject to the variation of individual clinical practices. Patients
with minimal or no comorbidities are frequently selected
the effects of the severity of the carotid stenosis and preop-
erative symptoms on outcomes of CEA. In fact, cardiac
arrhythmias were a specific exclusion factor for two of the
most well-known randomized controlled trials (Asymp-
tomatic Carotid Atherosclerosis Study [ACAS] and North
American Symptomatic Carotid Endarterectomy Trial,
[NASCET]).6,7However, CEA is frequently performed in
elderly patients with concomitant multiple and severe co-
morbid diseases.8This population is substantially different
from those typically enrolled in such trials, making exami-
ment of the application of CEA.
Chronic atrial fibrillation (AF) is a common comorbid
condition among CEA patients. Several prior studies have
documented a significantly increased risk of death or stroke
after CEA among patients with AF as a secondary find-
ing.9-11A prior study of risk factors for perioperative stroke
or death, which included more than 6000 patients from the
Ontario Carotid Endarterectomy Registry, found that pa-
death or stroke (odds ratio [OR] ? 1.75; P ? .0011).9
Patients with AF have also been found to be at higher risk
for stroke or death in a study that examined the effect of
cholesterol-lowering agents on outcomes of CEA10and in
a study that examined the effect of patient gender on CEA
The objective of this study is to determine whether
patients with AF have an increased risk of perioperative
From the Division of Vascular Surgery,aand the Department of Public
Health Sciences,bUniversity of Virginia Health System.
Reprint requests: George J. Stukenborg, PhD, Associate Professor of Public
Health Sciences, University of Virginia School of Medicine, PO Box
800821, Charlottesville, VA 22908 (e-mail: firstname.lastname@example.org).
The editors and reviewers of this article have no relevant financial relation-
ships to disclose per the JVS policy that requires reviewers to decline
review of any manuscript for which they may have a competition of
Copyright © 2010 by the Society for Vascular Surgery.
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Submitted Jul 1, 2009; accepted Aug 16, 2009.
JOURNAL OF VASCULAR SURGERY
336 Harthun and Stukenborg