Case Studies

Carotid Endarterectomy to Remove Retained Solitaire Stent
Retriever inside Carotid Stent after Mechanical Thrombectomy
Mary In-Ping Huang Cobb, MD,* Tony P. Smith, MD,† Patrick A. Brown, MD,†
L. Fernando Gonzalez, MD,* and Ali R. Zomorodi, MD*

Background: Tandem occlusions of the internal carotid artery (ICA) and middle
cerebral artery (MCA) occur in up to a third of patients with acute ischemic strokes
undergoing endovascular mechanical thrombectomy. Understanding open neurosurgical management of associated complications with this procedure is important.
Case Report: A 67-year-old man with acute onset of left hemiparesis and a tandem
right ICA and MCA occlusion. He underwent carotid stent angioplasty of a stenotic ICA, followed by attempted Solitaire stent retrieval of an MCA clot. On
withdrawal, the tines of the Solitaire stent lodged inside the Precise carotid stent.
The patient was started on aspirin, Plavix, and heparin infusion, and underwent
a carotid endarterectomy (CEA) with safe removal of the stents and primary vessel
repair. Conclusion: This is the first case reported to date of a Solitaire stent becoming lodged inside a Precise carotid stent, salvaged by CEA with safe removal
of the stents and primary vessel repair. We discuss the timing, indication, alternatives, and technical nuances of a CEA in this setting. Key Words: Carotid
endarterectomy—carotid stent—carotid stenosis—mechanical thrombectomy—retained
stent—solitaire stent—tandem occlusion.
© 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Introduction
Carotid endarterectomy (CEA) has become the primary
treatment for carotid stenosis, with carotid artery stenting
reserved for symptomatic patients with >70% stenosis and
at high risk for CEA (e.g., those with severe cardiac disease,
a history of CEA with recurrent stenosis, contralateral
From the *Duke University Hospitals, Department of Neurosurgery, Durham, North Carolina; and †Duke University Hospitals,
Department of Radiology, Division of Interventional Radiology, Durham,
North Carolina.
Received October 7, 2016; revision received January 25, 2017;
accepted February 9, 2017.
Address correspondence to Mary In-Ping Huang Cobb, MD, Duke
University Medical Center, Box 3807, Durham, NC 27701. E-mail:
maryih.cobb@duke.edu.
1052-3057/$ - see front matter
© 2017 National Stroke Association. Published by Elsevier Inc. All
rights reserved.
http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2017.02.015

e90

carotid occlusion, and history of radiation to the neck).1
Case studies have described the use of CEA as a salvage
therapy to remove either restenosed carotid stents deemed
unsalvageable with balloon-assisted stent angioplasty,
removal of a fragmented carotid stent, or stent migration.2-21
Surgical removal of an intra-arterial stent is risky secondary to the potential endothelialization of the stents
to the lumen of the vessel walls, making removal difficult without perforating the native vessel.
With 10%-30% of acute ischemic strokes presenting with
tandem internal carotid artery (ICA) and middle cerebral artery (MCA) occlusions, many patients are undergoing
deployment of both a temporary stent retriever (e.g., Solitaire [ev3 Neurovascular, Irvine, CA] or Trevo [Stryker,
Fremont, CA]) to remove a distal clot and a permanent
carotid stent (e.g., Precise Pro Rx [Cordis, Fremont, CA]
or Carotid Wall [Boston Scientific, Boston, MA]) to maintain
the patency of an underlying stenotic or dissected ICA.22-28
With recent data showing the effectiveness of mechanical

Journal of Stroke and Cerebrovascular Diseases, Vol. 26, No. 5 (May), 2017: pp e90–e95

CEA AS SALVAGE TO REMOVE RETAINED STENT

e91

thrombectomy for acute ischemic strokes, it is increasingly important to understand how to manage potential
complications associated with these procedures.22,29-33 In
the setting of tandem occlusions, we describe here the
first reported case of a CEA for the retrieval of a Solitaire stent lodged inside a carotid stent after mechanical
thrombectomy in the setting of a tandem ICA and MCA
stenosis causing an acute ischemic stroke.

Clinical Presentation
A 67-year-old man with a history of hypertension and
coronary artery disease, who presented with an acute onset
of left hemiparesis, dysarthria, and facial droop (National Institutes of Health Stroke Scale score 16). Computed
tomography (CT) of the brain showed no hemorrhage.
Intravenous tissue plasminogen activator was administered. CT angiogram showed a right carotid occlusion.
Within 6 hours of symptom onset, the patient underwent catheter angiography, which demonstrated an
occlusion of the right ICA (cervical segment) (Fig 1). He
underwent a balloon-assisted carotid stent angioplasty,
which recanalized the ICA. After opening up the ICA,
the tandem M1 occlusion was attacked with deployment of a Solitaire stent retriever (ev3 Neurovascular).
As the Solitaire stent was withdrawn, it lodged into the
tines of the Precise Pro Rx carotid stent (Cordis) (Fig 2).
The guide catheter was not passed through the stent.
Balloon angioplasty was not attempted because of the difficulty finding the lumen inside both the Solitaire and
the Precise stents. Snare retrieval was not performed
because of the high risk of perforation of the native vessel

Figure 2. Solitaire stent lodged inside a Precise carotid stent.

on removal. With antegrade flow into the anterior cerebral artery (ACA) and MCA, and time to thrombolysis
in cerebral infarction score (TICI) of 2b reperfusion distal
to the stent, the procedure was aborted.
The patient was placed on aspirin, clopidogrel (Plavix,
Bristol-Myers Squibb/Sanofi Pharmaceuticals Partnership, Bridgewater, NJ), and heparin guttae (gtt) at 600 U
an hour. Five days later, after his examination had improved and stabilized (National Institutes of Health Stroke
Scale score 12) and before the stents endothelialized, he
was brought to the operating room and underwent a CEA
for retrieval of the Solitaire stent and Precise carotid stent,
and primary reconstruction of the carotid stenosis.

Operative Nuances

Figure 1. Catheter angiogram showing right internal carotid artery occlusion.

The patient’s heparin gtt was held before anesthesia
induction. Neuromonitoring with somatosensory evoked
potentials (SSEPs) and electroencephalogram (EEG) was
established to provide evidence of vascular perfusion while
the patient was under general endotracheal anesthesia.
The standard latero-cervical incision was performed.
The carotid sheath was identified by palpation of the arterial pulse. The precise location of the stent inside the
carotid artery was confirmed by an intraoperative x-ray.
The carotid artery was circumferentially dissected away
from the carotid sheath. A temporary straight aneurysm
clip was placed on the ICA, just distal to the underlying stent, followed by a Sugita clip (Mizuho, Tokyo, Japan)
on the proximal common carotid artery. Two temporary
straight aneurysm clips were placed in the superior thyroid
artery and external carotid artery. It was important at this
point to exclude the stent from these clips.

M.I.-P.H. COBB ET AL.

e92

The length of the CEA was identified and marked, with
extension of the incision proximal to the underlying stent.
The adventitia of the common carotid artery was opened
with an 11 blade scalpel and Potts scissors. Dissection
was performed starting at the caudal end of the incision through the layers of the media and intima into the
native non-stent portion of the vessel. As the dissection
was carried cranially, the carotid stent was revealed,
showing apposition to an underlying hard thick layer of
calcified plaque and atherosclerosis. The tines of the stent
pressed unevenly against the lumen plaque, but there appeared to be no apposition against the native intimal wall.
Once the plane of the carotid stent was identified, dissection occurred more superficially, separating the plaque
and stent mass from the intima, using a nerve hook and
DeBakey forceps.
As the incision and dissection extended rostrally, the
retained Solitaire stent was identified inside the carotid
stent. With the ICA unclipped and backbleeding, the entire
plaque and stent mass was carefully removed caudally
en bloc through the native non-stent area (Fig 3). Careful
evaluation of the ICA was performed to rule out a dissection flap. Further dissection under heparinized saline
irrigation occurred with a ringed curette to fine comb additional atherosclerotic plaque away from the intimal walls.
Running sutures with a 6-0 prolene were used to close
the endarterectomy from rostral to caudal direction. Before

the last 2 sutures were placed, the aneurysm clip on the
external carotid artery (ECA) was temporarily removed
to wash additional debris. Once the sutures were tied,
the ECA aneurysm clip was removed, followed by the
common carotid artery and ICA.
There were no changes in EEG, SSEPs, or vital signs.
Intraoperative angiography was performed showing interval removal of the Solitaire and carotid stent, with
antegrade flow into the ACA and MCA. There was a small
dissection proximal to the CEA, and the endarterectomy was extended caudally. Care was taken to stitch
down the inside of the dissection flap to the native vessel
using a double-ended suture. Hemostasis was achieved.
Gelfoam was placed on top of the endarterectomy. The
carotid sheath was approximated loosely with a couple
of 4-0 neurilon sutures, followed by closure of the platysma and skin in layers. A tiny little suction drain was
left in overnight. Post-procedural CT angiogram showed
non–flow-limiting stenosis proximal to the CEA, and an
additional balloon-assisted carotid stent angioplasty was
performed without complication.

Discussion
This is the first described case of a CEA as a salvage
technique to remove a retained Solitaire stent and carotid
stent. Several case studies of salvage CEA procedures have
been described for the removal of a carotid stent.2-21 Prior
cases were performed for stent restenoses, migration, fracture, and entrapment of a distal embolic protection device.
None were performed in the setting of an acute ischemic stroke. Only a few studies involved a primary repair
after removal of the carotid stent, with the assistance of
a patch graft being the most common strategy, followed
by a reverse saphenous vein bypass (Table 1). In our case,
primary repair was achieved safely with the assistance
of intraoperative localization by x-ray and angiography,
in a patient who remained paralyzed, under general endotracheal anesthesia, with intracranial perfusion monitored
by potential changes in EEG and SSEPs.

Surgical Risk of Stent Removal

Figure 3. Gross specimen of the Solitaire stent, Precise carotid stent, and
calcified atherosclerotic plaque.

Surgical removal of an intraluminal stent is uncommon for the primary fear that the stent tines have penetrated
the lumen of the vessel walls and endothelialized, making
surgical dissection of the stent away from the intima cumbersome and unsafe. Shearing of the stent against the lumen
of the native vessels can compromise the integrity of the
native vessel, making it difficult for the surgeon to reconstruct the vessel.34,35 This could lead to the need for
a patch graft to assist in repair, or more complicated salvage
techniques such as vessel bypass, proximal vessel occlusion, or vessel trapping.11,15
In this case, the stent was intertwined in the plaque.
Our exposure was extra long to allow for exposure of

CEA AS SALVAGE TO REMOVE RETAINED STENT

e93

Table 1. Review of carotid endarterectomy cases for removal of diversion of stents
Author

No. of cases

Technique

Vale et al 19972
Johnson et al 19973
Calvey and Gough 19984
Reedy et al 20005
Leger et al 20016
Owens et al 20027

1
1
1
2
2
6

de Borst et al 20038

4

Akin et al 20049
Setacci et al 200510
de Vries et al 200511
Raithel 200512

1
3
1
8

Faggioli et al 200713

5

Jimenez et al 200814
Valibhoy et al 200715
King et al 200916
Soylu and Bayazit 201117
Reichmann et al 201118

1
1
1
1
15

Gonzalez et al 201119
Jost et al 201220

3
4

Stent removal and CEA with patch (3)
Stent removal and CEA with patch (3)
Stent removal and CEA (1)

Zheng et al 201321

1

Stent removal and CEA

Stent removal and CEA
Reversed saphenous vein bypass
Reversed saphenous vein bypass
Stent removal and CEA with patch
PTFE bypass
Stent removal and CEA (1)
Thrombolysis and stent removal with CEA (1)
Reversed saphenous vein bypass (2)
ICA to ECA transposition
Stent removal with CEA and patch
Stent removal with CEA and patch
Stent removal and CEA with patch
Stent removal and CEA
Stent removal and CEA with patch (6) or graft (2)
Stent removal and CEA (1)
Stent removal and CEA with patch (2)
Reversed saphenous vein bypass (2)
Stent removal and CEA (primary repair) (1)
Stent removal with CEA and patch
Stent removal with CEA and patch
Stent removal with CEA and patch
Stent removal and CEA with patch
Stent removal and CEA with patch (13)

Results
No complications
No complications
No complications
No complications
No complications
1 case of reversed vein
bypass thrombosis

Hemiparesis (1)
No complications (3)
No complication
No complication
No complications
No complications
No complications

No complication
No complication
No complication
No complication
Aphasia, hemiparesis (1)
Neck hematoma (2)
No complications (12)
No complication
Neck hematoma (1)
Aphasia, dysphagia (1)
No complications (2)
No complication

Abbreviations: CEA, carotid endarterectomy; ECA, external carotid artery; ICA, internal carotid artery; PTFE, polytetrafluoroethylene.

the native vessel above and below the stent. Following
this native plane between the plaque and the lumen in
an area with native vessel was important before dissection along the stent and plaque. Care was taken in both
cases to remove the stent through an exposed native vessel
segment to avoid penetration of thinned native vessel walls.
Prior studies had described difficulty cutting the artery
because of the metallic stent.2 In our case, there was no
need to cut the Precise stent or Solitaire stent because
both were deep, intertwined inside the plaque. Repair
and reconstruction need to occur quickly with proximal
control achieved at the compromise of limited intracranial perfusion through collateral vessels.

Alternative Treatments
Alternatives described elsewhere for carotid restenosis
including percutaneous balloon angioplasty with or without
carotid stent angioplasty were not available to our patient
because of the risk of crushing the poorly positioned

Solitaire stent through the vessel walls.36 Finding the true
lumen inside an obliquely positioned Solitaire stent would
be virtually impossible under fluoroscopic guidance.
Further, the relatively small size of the stent retriever to
the carotid stent would lead to poor apposition, even with
the stent fully expanded with balloon angioplasty.
Deployment of a Snare device to retrieve the Solitaire
stent into a large proximal catheter was not performed
because of the concern for unpredictable dissection or perforation of the native vessel. Navigating a Snare stent across
the lumen of the carotid stent and attaching it to the Solitaire stent without catching the carotid stent would be
challenging. Further, if the Snare device were to attach
to the Solitaire stent, the consequent movement of the
carotid stent as the Snare-Solitaire stent unit was withdrawn would be unpredictable.
Although not performed on this patient, transcranial
cerebral Dopplers can be performed to see if there is a
shower of emboli, with indication to treat more urgently if they are persistent with an associated change

e94

in neurologic examination. Complete vessel takedown is
another alternative; however, in this patient with an acute
ischemic stroke, it was evident that he was dependent
on vascularization from the right ICA.

Alternatives to Carotid Stent Placement in Setting of
Acute Tandem Occlusion
There is still ongoing debate over the appropriate time
to place a carotid stent after a mechanical thrombectomy in patients with tandem occlusions. Some advocate
for balloon angioplasty of the carotid stent stenosis, followed by removal of a distal occlusion with a stent
retriever. A few days later, after the patient is clinically
stable and loaded with dual antiplatelet agents, the patient
will return to the angiography suite for placement of a
carotid stent. However, with a tight stenosis causing an
acute distal occlusion, there is interval risk of a reocclusion without more urgently addressing the underlying
cause.
Further, the Penumbra aspiration device may serve as
an alternative for mechanical thrombectomy without the
use of a stent retriever.37 This technique involves no placement of a stent within a stent; however, most of the core
acute ischemic stroke trials showing efficacy involved use
of flow arrest with the proximal balloon catheter and a
distal stent retriever such as Solitaire or Trevo.22,29-33

Conclusion
In conclusion, we describe here the first study to date
of surgical removal of a stent retriever lodged inside a
carotid stent, followed by a primary vessel reconstruction and repair. Although rare, understanding the open
surgical management of this complication is important
to minimize the risk of stroke and dissection. In the landscape of increasing rates of endovascular mechanical
thrombectomy and carotid stent angioplasty in patients
with tandem ICA and MCA occlusions, we hope this report
provides additional insight on how to safely manage this
clinical scenario.

References
1. CMS, Decision Memo for Carotid Artery Stenting
(CAG-00085R). Centers for Medicare and Medicaid
Services. Available at: www.cms.gov. Accessed 24
November 2015.
2. Vale FL, Fisher WS 3rd, Jordan WD Jr, et al. Carotid
endarterectomy performed after progressive carotid
stenosis following angioplasty and stent placement. Case
Report J Neurosurg 1997;87:940-943.
3. Johnson SP, Fujitani RM, Leyendecker JR, et al. Stent
deformation and intimal hyperplasia complicating
treatment of a post-carotid endarterectomy intimal
flap with a Palmaz stent. J Vasc Surg 1997;25:764768.
4. Calvey T, Gough MJ. A late complication of internal
carotid artery stenting. J Vasc Surg 1998;27:753-755.

M.I.-P.H. COBB ET AL.
5. Reedy FM, Colonna M, Genovese V, et al. Successful
surgical treatment of two patients with restenosis after
previous stenting of the carotid artery. Eur J Vasc
Endovasc Surg 2000;20:99-101.
6. Leger AR, Neale M, Harris JP. Poor durability of carotid
angioplasty and stenting for treatment of recurrent artery
stenosis after carotid endarterectomy: an institutional
experience. J Vasc Surg 2001;33:1008-1014.
7. Owens EL, Kumins NH, Bergan JJ, et al. Surgical
management of acute complications and critical restenosis
following carotid artery stenting. Ann Vasc Surg
2002;16:168-175.
8. de Borst GJ, Ackerstaff RGA, Mauser HW, et al. Operative
management of carotid artery in-stent restenosis: first
experiences and duplex follow-up. Eur J Vasc Endovasc
Surg 2003;26:137-140.
9. Akin E, Knobloch K, Pichlmaier M, et al. Instent restenosis
after carotid stenting necessitating open carotid surgical
repair. Eur J Cardiothorac Surg 2004;26:442-443.
10. Setacci C, De Donato G, Setacci F, et al. Surgical
management of acute carotid thrombosis after carotid
stenting: a report of three cases. J Vasc Surg 2005;42:993996.
11. de Vries JP, Meijer RW, van den Berg JC, et al. Stent
fracture after endoluminal repair of a carotid artery
pseudoaneurysm. J Endovasc Ther 2005;12:612-615.
12. Raithel D. Complications of carotid artery stenting.
J Cardiovasc Surg (Torino) 2005;46:261-265.
13. Faggioli GL, Ferri M, Rossi C, et al. Carotid stent failure:
results of surgical rescue. Eur J Vasc Endovasc Surg
2007;33:58-61.
14. Jimenez JC, Moore WS, Lawrence PF, et al. Technical
strategies for recurrent carotid stenosis following
angioplasty and stenting. Ann Vasc Surg 2008;22:179184.
15. Valibhoy AR, Mwipatayi BP, Sieunarine K. Fracture of
a carotid stent: an unexpected complication. J Vasc Surg
2007;45:603-606.
16. King BN, Scher LA, Lipsitz EC. Refractory in-stent
restenosis following carotid artery stenting: a case report
and review of operative management. Vasc Endovascular
Surg 2009;43:306-311.
17. Soylu L, Bayazit M. Carotid endarterectomy performed
after carotid artery restenosis following stent migration.
Ann Vasc Surg 2011;25.
18. Reichmann BL, van Laanen JH, de Vries JP, et al. Carotid
endarterectomy for treatment of in-stent restenosis after
carotid angioplasty and stenting. J Vasc Surg 2011;54:87-92.
19. Gonzalez A, Drummond M, McCord S, et al. Carotid
endarterectomy for treatment of in-stent restenosis. J Vasc
Surg 2011;54:1167-1169.
20. Jost D, Unmuth SJ, Meissner H, et al. Surgical treatment
of carotid in-stent-restenosis: novel strategy and current
management. Thorac Cardiovasc Surg 2012;60:517-524.
21. Zheng J, Liu L, Cao Y, et al. Carotid endarterectomy with
stent removal in management of in-stent restenosis: a safe,
feasible, and effective technique. Eur J Vasc Endovasc
Surg 2014;47:8-12.
22. Berkhemer OA, Fransen PS, Beumer D, et al. A
randomized trial of intraarterial treatment for acute
ischemic stroke. N Engl J Med 2015;372:11-20.
23. Kappelhof M, Marquering HA, Berkhemer OA, et al.
Intra-arterial treatment of patients with acute ischemic
stroke and internal carotid artery occlusion: a literature
review. J Neurointerv Surg 2015;7:8-15.
24. Cohen JE, Gomori JM, Rajz G, et al. Extracranial carotid
artery stenting followed by intracranial stent-based

CEA AS SALVAGE TO REMOVE RETAINED STENT
thrombectomy for acute tandem occlusive disease.
J Neurointerv Surg 2015;7:412-417.
25. Maurer CJ, Joachimski F, Berlis A. Two in one:
endovascular treatment of acute tandem occlusions in
the anterior circulation. Clin Neuroradiol 2015;25:397-402.
26. Lescher S, Czeppan K, Porto L, et al. Acute stroke
and obstruction of the extracranial carotid artery
combined with intracranial tandem occlusion: results of
interventional revascularization. Cardiovascular and
interventional radiology. Cardiovasc Intervent Radiol
2015;38:304-313.
27. Dababneh H, Bashir A, Hussain M, et al. Endovascular
treatment of tandem internal carotid and middle cerebral
artery occlusions. J Vasc Interv Neurol 2014;7:26-31.
28. Stampfl S, Ringleb PA, Mohlenbruch M, et al. Emergency
cervical internal carotid artery stenting in combination
with intracranial thrombectomy in acute stroke. AJNR
Am J Neuroradiol 2014;35:741-746.
29. Campbell BC, Mitchell PJ, Kleinig TJ, et al. Endovascular
therapy for ischemic stroke with perfusion-imaging
selection. N Engl J Med 2015;372:1009-1018.
30. Goyal M, Demchuk AM, Menon BK, et al. Randomized
assessment of rapid endovascular treatment of ischemic
stroke. N Engl J Med 2015;372:1019-1030.
31. Saver JL, Goyal M, Bonafe A, et al. Solitaire™ with the
Intention for Thrombectomy as Primary Endovascular

e95
Treatment for Acute Ischemic Stroke (SWIFT PRIME) trial:
protocol for a randomized, controlled, multicenter study
comparing the Solitaire revascularization device with
IV tPA with IV tPA alone in acute ischemic stroke. Int
J Stroke 2015;10:439-448.
32. Saver JL, Goyal M, Bonafe A, et al. Stent-retriever
thrombectomy after intravenous t-PA vs. t-PA alone in
stroke. N Engl J Med 2015;372:2285-2295.
33. Jovin TG, Chamorro A, Cobo E, et al. REVASCAT trial
investigators: thrombectomy within 8 hours after symptom
onset in ischemic stroke. N Engl J Med 2015;372:22962306.
34. Gersak B, Gabrijelcic T. Successful surgical removal of
partially expanded Palmaz stent from external iliac artery.
Panminerva Med 1995;37:92-94.
35. Dwivedi AJ, Sharma D, Parks K. Management of a
misplaced endovascular stent in pulmonary artery. Am
Surg 2015;81:E151-E153.
36. Di Gioia G, Campanale CM, Mega S, et al. Percutaneous
treatment of recurrent in-stent restenosis of carotid artery
stenting: a case report and state-of-the-art review. Am
J Case Rep 2015;16:558-562.
37. Hussain SI, Zaidat OO, Fitzsimmons BF. The Penumbra
system for mechanical thrombectomy in endovascular
acute ischemic stroke therapy. Neurology 2012;79(13 Suppl
1):S135-S141.