A diffusion-weighted magnetic resonance
imaging-based study of transcervical carotid
stenting with flow reversal versus transfemoral
Ignacio Leal, MD,aAntonio Orgaz, MD,aÁngel Flores, MD,aJose Gil, MD,aRubén Rodríguez, MD,a
Javier Peinado, MD,aEnrique Criado, MD,band Manuel Doblas, MD,aToledo, Spain; and Ann Arbor,
Background: Transfemoral carotid artery stenting (CAS) has been associated with a high incidence of embolic phenomena
and silent brain infarction. The goal of this study was to compare the incidence of new ischemic cerebral lesions on
diffusion-perfusion magnetic resonance imaging (MRI) sequences after transcervical CAS performed with carotid flow
reversal vs stenting via transfemoral approach with distal filter protection.
Methods: During a 26-month period, 64 consecutive patients diagnosed with significant carotid stenosis by ultrasound
imaging were assigned to transcervical CAS with carotid flow reversal or a transfemoral approach with a distal filter. The
Rankin stroke scale was administered by an independent neurologist, and diffusion-weighted MRI (DW-MRI) studies
were performed <24 hours before and <24 to 48 hours after the procedure. DW-MRI studies were compared by two
neuroradiologists not involved in the study and blinded for time, clinical status, and treatment option. Hyperintense
DW-MRI signals found after the procedure were interpreted as postoperative ischemic infarcts. All patients were assessed
at 1, 6, and 12 months after the intervention.
Results: The distribution of demographic and pathologic variables was similar in both groups. All procedures were
technically successful, with a mean carotid flow reversal time of 22 minutes. Twenty-one (70%) and 23 patients (69.69%)
were symptomatic in the transcervical and transfemoral groups, respectively (P ? .869). After intervention, new
postprocedural DW-MRI ischemic infarcts were found in four transcervical (12.9%) and in 11 transfemoral (33.3%)
patients (P ? .03), without new neurologic symptoms. No major adverse events occurred at 30 days after the
intervention. All patients remained neurologically intact, without an increase in stroke scale scoring. All stents remained
patent, and all patients remained stroke-free during follow-up. In multivariate analysis, age (relative risk [RR], 1.022;
P < .001), symptomatic status (RR, 4.109; P < .001), and open-cell vs closed-cell stent design (RR, 2.01; P < .001) were
associated with a higher risk of embolization in the transfemoral group but not in the transcervical group.
Conclusions: These data suggest that transcervical carotid stenting with carotid flow reversal carries a significantly lower
incidence of new ischemic brain infarcts than that resulting from transfemoral CAS with a distal filter. The transcervical
approach with carotid flow reversal may improve the safety of CAS and has the potential to improve results in especially
vulnerable patients such as the elderly and symptomatic. (J Vasc Surg 2012;56:1585-90.)
The management of patients with carotid artery steno-
sis is evolving. A major concern with transfemoral carotid
artery stenting (CAS) with a distal filter for cerebral protec-
tion is its potential for cerebral embolization. The low
incidence of clinically apparent neurologic complications of
CAS is in stark contrast with the high incidence of silent
brain infarction demonstrated by diffusion-weighted mag-
netic resonance imaging (DW-MRI) after transfemoral
CAS. Data from the only two recently published prospec-
tive trials comparing filter-protected vs unprotected trans-
femoral CAS demonstrated a higher incidence of new isch-
emic brain lesions after filter-protected transfemoral
The results of CAS are clearly influenced by the access
route and cerebral protection methods; however, these
factors have not been properly evaluated in any trial. The
risk of embolic complications with transfemoral carotid
stenting is related to instrumentation of the arch and prox-
imal supra-aortic trunks, crossing of the carotid lesion
without protection, and use of distal filter protection de-
vices of questionable benefit.
Transcervical CAS with flow reversal for cerebral pro-
tection has the potential advantage of reducing the inci-
dence of complications associated with transfemoral CAS
with distal filter protection. This is suggested by DW-MRI
studies after transcervical CAS with carotid flow reversal
showing a remarkably lower incidence of postprocedural
ischemic brain infarcts compared with patients undergoing
From the Vascular Surgery Section, Complejo Hospitalario de Toledo,
Toledoa; and the Vascular Surgery Section, Department of Surgery,
University of Michigan School of Medicine, Ann Arbor.b
Author conflict of interest: none.
Reprint requests: Ignacio Leal, MD, Hospital Virgen de la Salud, Servicio
Cirugía Vascular, Avenida Barber 30, 45190 Toledo, Spain (e-mail:
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 conflict of interest.
Copyright © 2012 by the Society for Vascular Surgery.
transfemoral CAS with distal filter protection.3,4This study
constitutes our institutional experience comparing trans-
cervical CAS with flow reversal vs CAS with transfemoral
Study design. The study was designed as a single-
center, prospective, nonrandomized study in accordance
with the institutional board policies and regulations at the
Complejo Hospitalario de Toledo, Spain. It was approved
and monitored by the Institutional Review Board, and all
patients gave informed consent before enrollment.
Sample size calculations were based on previously re-
ported incidences of new ischemic lesions on postoperative
DW-MRI in CAS series. To have an 80% power of detect-
ing differences of at least 30% at a two-tailed level of 0.05,
34 patients were needed in each group. Enrollment was
performed between April 2008 and June 2009. The first
interventions were in 31 patients in the transcervical co-
hort, and they were the subject of a previous publication.3
Inclusion and exclusion criteria. All patients consid-
ered for the study had to be in a high-risk category for
carotid endarterectomy (CEA). Patients were invited to
participate if they had an extracranial internal carotid artery
stenosis ?70% and a minimum distance of 5 cm from the
carotid bifurcation to the clavicle, as determined by an
ultrasound study. Exclusion criteria included allergy to
heparin, aspirin, clopidogrel, or iodinated contrast agents,
contraindication to MRI studies, intracranial bleeding,
hemorrhagic stroke or any stroke with mass effect demon-
strated on MRI or computed tomography ?4 weeks of the
index procedure, dementia or neurologic illness that might
confound the neurologic evaluation during the study, total
internal carotid artery occlusion, or common carotid artery
calcification with contraindication for puncture or sheath
Interventional technique. All patients were treated
preoperatively with aspirin and clopidogrel. All procedures
were performed by vascular surgeons experienced in CAS
and done under local anesthesia with clinical monitoring of
Patients in the transfemoral group received heparin
(100 IU/kg) to achieve an activated clotting time of be-
tween 200 and 250 seconds. A 100-cm-long Guider Soft
Tip XF (Boston Scientific, Miami, Fla) or Ver 135 (Cordis,
Miami Lakes, Fla) guide catheter was used to introduce the
filter guidewire, crossing the stenosis, and the cerebral
protection device, a self-expanding Filter Wire EZ (Boston
Scientific), was deployed in the cervical portion of the
a 3-mm percutaneous transluminal angioplasty balloon
catheter when the lesion lumen was estimated to be smaller
than the diameter of the stent delivery system. A self-
expandable Carotid Wallstent (Boston Scientific) or Pro-
tégé Rx (ev3 Endovascular, Minneapolis, Minn) was
mounted on the protection device guidewire and deployed
across the stenosis. The stent was dilated with an Ultrasoft
SV angioplasty balloon (5- to 6-mm diameter ? 20-mm
long; Boston Scientific). Atropine sulfate (1 mg) was intra-
venously administered before balloon inflations to prevent
carotid sinus stimulation. Then, the filter was removed.
Our technique for transcervical CAS with flow reversal
has been published before.5Systemic anticoagulation with
intravenous heparin (100 U/kg body weight) was con-
ducted before carotid occlusion and was not reversed with
protamine at the completion of the procedure. The tech-
nique consists of a short incision above the edge of the
clavicle between the heads of the sternocleidomastoid mus-
cle. A short segment of the common carotid artery and
jugular vein are dissected, and the common carotid artery is
controlled with a Rummel loop. Sheaths (8F) are placed in
the jugular vein and the common carotid artery and con-
is ascertained by arteriography. Then, under flow reversal, a
0.014-inch guidewire is used to cross the carotid lesion,
and the stenting is conducted under flow reversal in a
Both groups were prescribed a daily dose of acetylsali-
cylic acid (100 mg) and clopidogrel (75 mg) for 1 month
after the procedure.
Neurologic evaluation. DW-MRI was acquired with
sagittal T1 sequences, T2-weighted axial, fluid-attenuated
inversion recovery axial, and apparent diffusion coefficient
map. In addition, T1-weighted axial and sagittal sequences
were conducted after contrast administration. DW-MRIs
were conducted ?24 hours before and 24 to 48 hours after
the procedure. Imaging was performed on a 1.5 T Signa
HD unit (General Electric, Buckinhamshire, UK).
Preoperative and postoperative DW-MRIs were read
by two independent neuroradiologists unaware of the pa-
tient’s clinical status and blinded to the timing (preopera-
tive or postoperative) of the paired scans. Ischemic lesions
in the cerebral hemispheres, size, and location were re-
corded by each reader and compared with that of the
All patients were evaluated by a neurologist before and
after the procedure using the Rankin stroke scale and
including sensory, motor, and autonomic testing. Neuro-
logic deficits lasting ?24 hours were defined as stroke, and
those lasting ?24 hours were defined as transient ischemic
All patients were evaluated 30 days after surgery with a
clinical assessment and carotid ultrasound imaging. Addi-
tional follow-up visits were performed at 6 and 12 months.
Technical success was considered when the stent was satis-
factorily deployed with ?30% residual stenosis in the target
Data analysis. The primary study end point was the
evidence of new ischemic lesions on postoperative DW-
MRI studies. Continuous variables are expressed as the
mean and standard deviation (SD). Normality distribution
was assessed using the Kolmogorov-Smirnov test. Cate-
goric data were compared using the Fisher exact test and
are summarized as absolute frequencies and percentages.
Comparison of continuous variables between cohorts was
done with the unpaired Student t-test. Statistical signifi-
JOURNAL OF VASCULAR SURGERY
1586 Leal et al
cance was defined as two-sided P ? .05. Statistical analysis
was conducted using SPSS 15.0 software (SPSS Inc, Chi-
We used binary regression models to compare MRI
outcome measures between treatment groups. Interactions
between the effect of treatment on the primary outcome
measure and selected variables (age, sex, operator, type of
stent used, symptomatic status) were investigated and ad-
justed for any significant imbalances in baseline character-
istics, if necessary.
Patient enrollment. Between April 2008 and June
2009, 64 consecutive patients were diagnosed with signif-
to the inclusion and exclusion criteria, 64 (58 men, 6
women) patients, with a mean age of 72.04 (SD, 10.97)
years, were enrolled. The procedures were done in two
separate periods. During the first part of the study, 31
patients underwent transcervical carotid stenting. During
the second part of the study, 33 patients underwent trans-
femoral CAS with distal filter protection.
Patient population. Comorbid conditions are sum-
marized in Table I. The two groups did not differ signifi-
cantly in demographics, symptomatic status, degree of ste-
nosis, and contralateral disease.
Procedural results. We used 45 Wallstents (Boston
Scientific, Natick, Mass) and 19 Protégé Rx (ev3 Endovas-
cular), without reaching a significant difference in the dis-
tribution of the types of stent (P ? .647). Stent selection
was determined by lesion characteristics and surgeon pref-
erence. A closed-cell design was used whenever possible
and an open-cell one when size discrepancies between
common and internal carotid arteries or tortuosities were
found. Predilatation was performed in three patients in the
transcervical group and in two in the transfemoral group
(P ? .694), using 3- to 4-mm diameter ? 2-cm-long
balloons inflated to 10 atm.
All procedures were technically successful without
(?30%) residual stenosis. Mean surgical time was 46 (SD,
5.05) minutes in the transcervical group and 52 (SD,
10.14) minutes in the transfemoral group, which was not
significantly different (P ? .324). Intolerance to carotid
there were no changes in the stroke scale in any patient in
either group. No strokes or transient ischemic attacks oc-
curred. There were no complications related to access site
in either group.
the preoperative DW-MRI study and surgical procedure
was 13.5 (SD, 2.4) hours in the transcervical group and
11.6 (SD, 2.1) hours in the transfemoral group, without
significant differences between groups (P ? .564). The
delay between procedures and the postoperative DW-MRI
study was 21.3 (SD, 1.5) hours in the transcervical group
and 20.4 (SD, 2.1) hours in transfemoral group (P ?
and DW-MRI studies.
.354). Results from DW-MRI evaluation are summarized
in Table II.
New postprocedural DWI-MRI–detected cerebral
ischemic lesions were found in four patients (12.9%) in the
transcervical group. These four patients developed one
(two patients), two (one patient), and five (one patient)
ischemic lesions, respectively. All lesions were subcortical,
Table I. Comorbid conditions
(n ? 31)
(n ? 33)
Age, mean (SD) years
Pre-op Rankin, mean
68.1 (10.7) 67.2 (10.01).869
5 (16.13)3 (9.68).394
0.6605 (1.14)0.6745 (1.04).305
ICA, Internal carotid artery; SD, standard deviation.
aData are shown as number (%), unless stated otherwise.
bMorphology was assessed according to echolucency criteria. Type 1: dom-
inantly echolucent; type 2: substantially echolucent with small areas of
echogenicity; type 3: dominantly echogenic with small areas of echolucency;
type 4: uniformly echogenic; and type 5: not classified owing to acoustic
Table II. Results from diffusion-weighted magnetic
resonance imaging (DW-MRI) evaluation
(n ? 31)
(n ? 33)
Patients with new
No. of new lesions
Localization of new
4 (12.90)11 (33.33) .03
JOURNAL OF VASCULAR SURGERY
Volume 56, Number 6
Leal et al 1587
ipsilateral to the treated side, ?5 mm in diameter, and
In the transfemoral group, new lesions were found in
11 of the 33 patients (33.3%) enrolled, one in nine patients
and two in the remaining two. Eleven ischemic lesions
(84.3%) were ipsilateral and two (15.7%) were contralat-
eral. All were ?5 mm, localized in the white matter, and
asymptomatic. The difference in the incidence of new isch-
groups (12.9% vs 33.3%) was significant (P ? .03).
The Rankin stroke scale did not deteriorate in any
patient. Postoperatively, the Rankin scale slightly improved
in the transcervical and transfemoral groups, although this
difference did not reach significance.
Evaluation of predictors of embolization. In the
multivariate analysis, none of the tested variables (age, sex,
operator, type of stent used, symptomatic status) reached
significance to predict the presence of embolization in the
postoperative DW-MRI studies.
Adjusting analysis by type of treatment, age (relative
1.041; P ? .001), recent symptomatic status (RR, 4.109;
95% CI, 1.74-9.65; P ? .001), and closed-cell vs open-cell
stent type (RR, 0.082; 95% CI, 0.019-0.359; P ? .001)
were independent predictors of embolization in the trans-
femoral group but not in the transcervical group.
Follow-up. All patients were evaluated with neuro-
logic evaluation and carotid ultrasound imaging at 1 and 6
months, at 1 year, and yearly thereafter. Mean follow-up
time was 23.25 months. No new neurologic events, deaths,
period. The Rankin stroke scale remained unchanged in all
patients. According to the ultrasound evaluation, all stents
remained patent, with no signs of restenosis.
CAS is currently an accepted alternative treatment for
carotid stenosis. Although early case series and registries
reported low rates of periprocedural complications risk,6-11
recent large randomized trials comparing CAS with CEA
have yielded controversial results.12-14
The risk of stroke associated with CAS is clearly related
to embolic phenomena that occur during the intravascular
instrumentation of the aortic arch, supra-aortic trunks, and
carotid plaque itself throughout the procedure, as has been
demonstrated with transcranial Doppler monitoring.15
A more sensitive tool for the detection of periproce-
dural embolization producing acute cerebral ischemia dur-
ing CAS is MRI diffusion-perfusion imaging.16-19Cyto-
toxic cell swelling that occurs as an immediate response to
neuronal ischemia causes an increase in the diffusion signal
that correlates with perfusion imaging results in the gener-
ation of hyperintense images corresponding to areas of
acute cerebral ischemia.20,21
Our single-center results are revealing. The existence of
a significant difference in the incidence of new ischemic
lesions on postoperative DWI-MRI between transcervical
and transfemoral groups is very consistent with published
Distal filter use can be associated with internal carotid
artery spasm, increased crossing profile for the initial wire
access, and technical misadventures in attempts to retrieve
the filter after stent deployment.22The current generation
of antiembolic filters also have important limitations: First,
commercially available filters have pore sizes of 100 to 150
?m; meanwhile, high-volume microemboli from ?60 ?m
have been demonstrated in experimental models at all
Second, the absence of neuroprotection creates a prob-
lem during aortic arch manipulation, accessing the com-
mon carotid artery, and while crossing the stenosis, which
are highly emboligenic maneuvers, according to research
conducted with continuous transcranial Doppler imag-
the contralateral hemispheric lesions found in two of 11
patients with new lesions in the transfemoral group. Simi-
larly as in previously published CEA series and unlike in the
transfemoral group, no contralateral hemispheric infarcts
were found in the transcervical cohort.
In the four patients in whom new lesions were docu-
mented in the transcervical group, flow interruptions oc-
curred because the carotid sheath was dislodged during the
procedure. All interruptions were due to movement and
exit of the carotid sheath by accidental manipulation in the
surgical field, needing to interrupt flow reversal, and in
some cases, carotid artery clamping was required to rein-
troduce the sheath. Ensuring the stability of the arterial
sheath is crucial to maintain a stable and constant flow
reversal. There are two maneuvers to achieve this: first,
fixing the sheath to the patient’s skin, and second, routing
the sheath through a skin and a subcutaneous tunnel cre-
ated from the clavicle to the carotid sheath. As seen in our
results, all patients with an unstable arterial access devel-
oped new lesions in postoperative DW-MRI, revealing the
transcendency of this fact, which probably must be im-
proved in the technique.
The sensitivity in acute lesion detection varies among
different MRI systems, so it is difficult to compare our
results with those of other studies. However, the low 12.9%
incidence in the transcervical group is comparable to the
best series of CEA and a great improvement over the results
of CAS with distal filters. The results of this work also
confirm previously reported transcervical series.25Based on
our technique, a novel transcervical access and cerebral
embolic protection system (MICHI Neuroprotection Sys-
tem; Silk Road Medical Inc, Sunnyvale, Calif) has shown
similar low DW-MRI rates.26
Our study has several limitations that should be ac-
knowledged. First, it is a nonrandomized single-center
different and consecutive periods over time to develop a
consecutive sampling, including every patient who met
inclusion and exclusion criteria. Randomization reduces
allocation bias, balancing both known and unknown prog-
JOURNAL OF VASCULAR SURGERY
1588 Leal et al
nostic factors in the assignment of treatment; however, the
two intervention groups are comparable in all of the main
demographic and pathologic variables.
Second, we used DW-MRI to compare silent brain
infarcts occurring after the two different techniques, but
the real clinical relevance of postoperative DW-MR lesions
has yet to be clarified. The effect of these new hyperintense
signals that do not correlate with clinical events is still
unknown, and some of these lesions may disappear over
time.4,27The long-term effect of these lesions may be
associated with an increased risk of dementia and cognitive
impairment,28although this association is still uncertain.29
The need to surgically access both the common carotid
artery and jugular vein could be considered a drawback of
our technique. However, no wound complications oc-
curred in this study, and also, no cranial nerve injury has
been reported with this approach. Our technique focuses
on improving results of CAS and overcoming limitations of
transfemoral access and filters. Results regarding neuro-
logic complications, even asymptomatic, make this tech-
nique probably comparable to CEA, although the latter
continues to be the gold standard treatment of carotid
artery stenosis in most patients. However, CAS is undoubt-
edly a very welcome addition to our armamentarium. Some
of the main issues that appear to limit its usefulness and
applicability are probably cerebral embolization and cathe-
ter and device access to the target lesion. Transcervical CAS
with flow reversal overcomes limitations in access to the
lesion, and as shown in this study, also cerebral emboliza-
Age and symptomatic status are risk factors for peripro-
cedural cerebrovascular events in the subgroup analysis of
large trials.30In our experience, age and symptomatic
status were risk factors for new embolization in the trans-
of CAS in octogenarian patients has been questioned in
several large trials. In the Carotid Revascularization Endar-
terectomy Versus Stenting Trial (CREST) study,31patients
aged ?70 years who underwent stenting had fewer adverse
events—combined rate of death, stroke or myocardial in-
farction—than patients who underwent CEA.
A recent analysis examined the effect of age on the
CAS-to-CEA relative efficacy using proportional hazard
models.32In this analysis, age acted as a treatment effect
modifier for the primary end point. For CAS, risk for the
primary end point increased with age, mainly by stroke
events as the primary contributor to the overall effect
The results of our study are consistent with recent data
that suggest that age by itself is associated in a weak but
significant way (RR, 1.022; 95% CI, 1.021-1.041; P ?
.04), with an increased risk of embolization by DW-MRI
evaluation. However, this effect is only observed in the
transfemoral group and not in the transcervical group.
Similarly, symptomatic status is a strong predictor of
the presence of new ischemic lesions in postoperative MRI
studies (RR, 4.109; 95% CI, 1.74-9.65; P ? .01) but only
in the transfemoral group. Comparative results between
did not reach significance, although the incidence of ad-
verse events was higher in the symptomatic group.
There are conflicting publications in the current litera-
ture about the influence of stent design on the outcome of
CAS, and results of our work are also conflicting.33-37No
differences were found between the two designs, consider-
ing all individuals, for the contribution of risk in the occur-
rence of new lesions in MRI studies, which is consistent
with recent studies. However, the adjusted analysis by the
type of procedure showed a slight but significant difference
in favor of closed-cell stents but only in the transfemoral
group (RR, 0.082; 95% CI, 0.019-0.359; P ? .001).
operative lesions should be interpreted with caution, given
the small sample size and the small number of new lesions.
These two main factors make this model relatively under-
powered to identify independent predictors of the study
outcome. However, the existence of worse prognostic data
in older patients, symptomatic patients, and CAS with
open-cell stents only in the transfemoral group could be
critical subgroups that benefit most from the use of the
transcervical approach with flow reversal.
Our data strongly suggest that transcervical carotid
stenting with carotid flow reversal may produce a signifi-
cantly lower incidence of cerebral embolization compared
with conventional transfemoral carotid stenting procedures
with distal filter protection. Age, recent symptomatic sta-
tus, and stent design were significantly associated with a
higher incidence of new embolic lesions in the transfemoral
group but not in the transcervical group.
Conception and design: IL, AO, AF, JG, RR, JP, EC, MD
Analysis and interpretation: IL, EC, MD
Data collection: IL, RR, JP
Writing the article: IL
Critical revision of the article: IL, AO, AF, JG, RR, JP, EC,
Final approval of the article: IL, AO, AF, JG, RR, JP, EC,
Statistical analysis: IL
Obtained funding: IL, MD
Overall responsibility: IL
1. Barbato JE, Dillavou E, Horowitz MB, Jovin TG, Kanal E, David S, et
al. A randomized trial of carotid artery stenting with and without
cerebral protection. J Vasc Surg 2008;47:760-73.
2. Macdonald S, Evans DH, Griffiths PD, McKevitt FM, Venables GS,
Cleveland TJ, et al. Filter-protected versus unprotected carotid artery
stenting: a randomised trial. Cerebrovasc Dis 2010;29:282-9.
3. Leal JI, Orgaz A, Fontcuberta J, Flores A, Doblas M, Garcia-Benassi
JM, et al. A prospective evaluation of cerebral infarction following
transcervical carotid stenting with carotid flow reversal. Eur J Vasc
Endovasc Surg 2010;39:661-6.
4. Faraglia V, Palombo G, Stella N, Rizzo L, Taurino M, Bozzao A.
Cerebral embolization during transcervical carotid stenting with flow
JOURNAL OF VASCULAR SURGERY
Volume 56, Number 6
Leal et al 1589
reversal: a diffusion-weighted magnetic resonance study. Ann Vasc Surg Download full-text
5. Criado E, Doblas M, Fontcuberta J, Orgaz A, Flores A. Transcervical
carotid artery angioplasty and stenting with carotid flow reversal: surgi-
cal technique. Ann Vasc Surg 2004;18;257e61.
6. Gray WA, Hopkins LN, Yadav S, Davis T, Wholey M, Atkinson R, et al.
ARCHe Trial Collaborators. Protected carotid stenting in high-surgical-
risk patients: the ARCHeR results. J Vasc Surg 2006;44:258-69.
7. Iyer SS, White CJ, Hopkins LN, Katzen BT, Safian R, Wholey MH, et
al. BEACH Investigators. Carotid artery revascularization in high-
J Am Coll Cardiol 2008;51:427-34.
8. Hopkins LN, Myla S, Grube E, Wehman JC, Levy EI, Bersin RM, et al.
Carotid artery revascularization in high surgical risk patients with the
NexStent and the FilterWire EX/EZ: 1 year results in the CABERNET
tria. Catheter Cardiovasc Interv 2008;71:950-60.
9. Safian RD, Bresnahan JF, Jaff MR, Foster M, Bacharach JM, Maini B, et
al. CREATE Pivotal Trial Investigators. Protected carotid stenting in
high-risk patients with severe carotid artery stenosis. J Am Coll Cardiol
10. Higashida RT, Popma JJ, Apruzzese P, Zimetbaum P, MAVErIC I and
II Investigators. MAVErIC I and II investigators. Evaluation valuation
of the Medtronic exponent self-expanding carotid stent system with the
Medtronic guardwire temporary occlusion and aspiration system in the
treatment of carotid stenosis: combined from the MAVErIC
(Medtronic AVE Self-expanding CaRotid Stent System with distal
protection In the treatment of Carotid stenosis) I and MAVErIC II
trials. Stroke 2010;41:e102-9.
11. Gray WA, Yadav JS, Verta P, Scicli A, Fairman R, Wholey M, et al.
CAPTURE Trial Collaborators. The CAPTURE registry: predictors of
outcomes in carotid artery stenting with embolic protection for high
surgical risk patients in the early post-approval setting. Catheter Car-
diovasc Interv 2007;70:1025-33.
12. Massop D, Dave R, Metzger C, Bachinsky W, Solis M, Shah R, et al.
SAPPHIRE Worldwide Investigators. Stenting and angioplasty with
protection in patients at high-risk for endarterectomy: SAPPHIRE
worldwide registry first 2,001 patients. Catheter Cardiovasc Interv
13. Mas JL, Chatellier G, Beyssen B, Branchereau A, Moulin T, Becquemin
JP, et al; EVA-3S Investigators. Endarterectomy versus stenting in
patients with symptomatic severe carotid stenosis. N Engl J Med
14. Featherstone RL, Brown MM, Coward LJ; ICSS Investigators. Inter-
national carotid stenting study: protocol for a randomised clinical trial
comparing carotid stenting with endarterectomy in symptomatic ca-
rotid artery stenosis. Cerebrovasc Dis 2004;18:69-74.
15. Crawley F, Stygall J, Lunn S, Harrison M, Brown MM, Newman S.
Comparison of microembolism detected by transcranial Doppler and
neuropsychological sequelae of carotid surgery and percutaneous
transluminal angioplasty. Stroke 2000;31:1329-34.
16. Lövblad KO, Jakob PM, Chen Q, Baird AE, Schlaug G, Warach S, et al.
Turbo spin-echo diffusion-weighted MR of ischemic stroke. AJNR
Am J Neuroradiol 1998;19:201-8; discussion 209.
17. Meyer JR, Gutierrez A, Mock B, Hebron D, Prager JM, Gorey MT, et
al. High-b-value diffusion-weighted MR imaging of suspected brain
infarction. AJNR Am J Neuroradiol 2000;21:1821-9.
18. Hammer FD, Lacroix V, Duprez T, Grandin C, Verhelst R, Peeters A,
et al. Cerebral microembolization after protected carotid artery stenting
Surg 2005;42:847-53; discussion 853.
19. Jaeger HJ, Mathias KD, Hauth E, Drescher R, Gissler HM, Hennigs S,
et al. Cerebral ischemia detected with diffusion-weighted MR imaging
after stent implantation in the carotid artery. AJNR Am J Neuroradiol
20. Moseley ME, Cohen Y, Mintorovitch J, Chileuitt L, Shimizu H,
Kucharczyk J, et al. Early detection of regional cerebral ischemia in cats:
comparison of diffusion- and T2-weighted MRI and spectroscopy.
Magn Reson Med 1990;14:330-46.
21. Yoneda Y, Tokui K, Hanihara T, Kitagaki H, Tabuchi M, Mori E.
Diffusion-weighted magnetic resonance imaging: detection of ischemic
injury 39 minutes after onset in a stroke patient. Ann Neurol 1999;45:
22. Kwon BJ, Han MH, Kang HS, Jung C. Protection filter-related events
in extracranial carotid artery stenting: a single-center experience. J
Endovasc Ther 2006;13:711-22.
23. Coggia M, Goëau-Brissonnière O, Duval JL, Leschi JP, Letort M,
Nagel MD. Embolic risk of the different stages of carotid bifurcation
balloon angioplasty: an experimental study. J Vasc Surg 2000;31:
24. Ribo M, Molina CA, Alvarez B, Rubiera M, Alvarez-Sabin J, Matas M.
Transcranial Doppler monitoring of transcervical carotid stenting with
flow reversal protection: a novel carotid revascularization technique.
25. Schmidt A, Diederich KW, Scheinert S, Bräunlich S, Olenburger T,
Biamino G, et al. Effect of two different neuroprotection systems on
microembolization during carotid artery stenting. J Am Coll Cardiol
26. Pinter L, Ribo M, Loh C, Lane B, Roberts T, Chou TM, et al. Safety
and feasibility of a novel transcervical access neuroprotection system
for carotid artery stenting in the PROOF study. J Vasc Surg 2011;54:
27. Cremonesi A, Setacci C, manetti R, de Donato G, Setacci F, Balestra G,
et al. Carotid angioplasty and stenting: lesion related treatment strate-
gies. EuroIntervention 2005;1:289-95.
28. Zhou W, Dinishak D, Lane B, Hernandez-Boussard T, Bech F, Rosen
A. Long-term radiographic outcomes of microemboli following carotid
interventions. J Vasc Surg 2009;50:1314-9.
N Engl J Med 2003;348:1215-22.
30. Wasser K, Pilgram-Pastor SM, Schnaudigel S, Stojanovic T, Schmidt H,
Knauf J, et al. New brain lesions after carotid revascularization are not
associated with cognitive performance. J Vasc Surg 2011;53:61-70.
31. Silver FL, Mackey A, Clark WM, Brooks W, Timaran CH, Chiu D, et al;
CREST Investigators. Safety of stenting and endarterectomy by symp-
tomatic status in the Carotid Revascularization Endarterectomy Versus
Stenting Trial (CREST). Stroke 2011;42:675-80.
32. Voeks JH, Howard G, Roubin GS, Malas MB, Cohen DJ, Sternbergh
WC 3rd, et al; CREST Investigators. Age and outcomes after carotid
stenting and endarterectomy: the carotid revascularization endarterec-
tomy versus stenting trial. Stroke 2011;42:3484-90.
33. Schillinger M, Minar E. Matching carotid anatomy with carotid stents.
J Cardiovasc Surg (Torino) 2008;49:723-7.
34. Bosiers M, Deloose K, Verbist J, Peeters P. Carotid artery stenting:
which stent for which lesion? Vascular 2005;13:205-10.
35. Jansen O, Fiehler J, Hartmann M, Brückmann H. Protection or nonpro-
tection in carotid stent angioplasty: the influence of interventional tech-
niques on outcome data from the SPACE trial. Stroke 2009;40:841-6.
36. Maleux G, Marrannes J, Heye S, Daenens K, Verhamme P, et al.
Outcome of carotid artery stenting at 2 years follow-up: comparison of
nitinol open cell versus stainless steel closed cell stent design. J Cardio-
vasc Surg (Torino) 2009;50:669-75.
37. Jim J, Rubin BG, Landis GS, Kenwood CT, Siami FS, Sicard GA; SVS
Outcomes Committee. Society for Vascular Surgery Vascular Registry
evaluation of stent cell design on carotid artery stenting outcomes. J
Vasc Surg 2011;54:71-9.
Submitted Mar 28, 2012; accepted May 31, 2012.
JOURNAL OF VASCULAR SURGERY
1590 Leal et al