Endovascular management of carotid arterystenosis secondary to sclerosing mediastinitisChristopher J. Smolock, MD,a Shanda Blackmon, MD,b Zsolt Garami, MD,a andHeitham T. Hassoun, MD,a Houston, Tex

Sclerosing mediastinitis is a rare, progressive condition characterized by extensive fibrotic reaction. We report the firstknown case of symptomatic, extrinsic compression of the carotid artery by fibrotic extension of sclerosing mediastinitis.A 54-year-old woman began experiencing neurologic symptoms from extension of a known mediastinal mass resulting in70% to 79% stenosis of the right internal carotid artery. The stenosis was treated with endovascular stenting. Completionangiogram revealed a good result with <10% residual stenosis. At 18-month follow-up, the patient was symptom freewithout evidence of re-stenosis. Endovascular therapy provides a novel and durable solution in the midterm to this very

rare problem. (J Vasc Surg 2012;56:492-5.)

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Sclerosing mediastinitis (SM) is a rare, slowly progres-sive condition characterized by an extensive fibrotic reac-tion in the mediastinum. Compression of mediastinal struc-tures related to SM has been reported. However, we reportthe first known case of symptomatic, extrinsic compressionof the carotid artery by fibrotic extension of sclerosingmediastinitis along with its endovascular treatment.

CASE REPORT

A 54-year-old woman with a history of hypothyroidism,asthma, and previously asymptomatic mediastinal mass presentedcomplaining of neurologic symptoms, vertigo, and syncope, alongwith a new finding of right common carotid artery stenosis. Hermediastinal mass was diagnosed as sclerosing mediastinitis and hadbeen stable in size during years of follow-up. However, evaluationby computed tomography angiography (CTA) and ultrasound,upon development of new neurologic symptoms, revealed exten-sion of the mediastinal mass cephalad, encasing the aortic arch andgreat vessels and continuing upward to the right carotid bifurca-tion (Fig 1). The patient had no other symptoms indicative ofcervical or mediastinal compression, ie, airway compromise, para-lyzed diaphragm, tongue deviation, or bradycardia. Additionally,the patient had no signs of inflammatory response by fever orlaboratory tests. Peak systolic velocity of the internal carotid arterywas 403 cm/s, interpreted as 70% to 79% stenosis (Fig 2). Flowwas absent in the right vertebral artery. Transcranial Doppler(TCD) examination confirmed the findings and demonstratedaltered cerebral perfusion in such a way that the posterior circula-

From the Department of Cardiovascular Surgery, Methodist DeBakey Heartand Vascular Center,a and Department of Surgery,b The MethodistHospital.

Author conflict of interest: none.Reprint requests: Heitham T. Hassoun, MD, Department of Cardiovascular

Surgery, Methodist DeBakey Heart and Vascular Center, Houston, TX77030 (e-mail: hhassoun@tmhs.org).

The editors and reviewers of this article have no relevant financial relationshipsto disclose per the JVS policy that requires reviewers to decline review of anymanuscript for which they may have a conflict of interest.

0741-5214/$36.00

(Copyright © 2012 by the Society for Vascular Surgery.doi:10.1016/j.jvs.2012.01.058

492

ion relied on flow from the stenotic right carotid artery, thusesulting in posterior circulation neurologic symptoms.

Due to the patient’s new development of symptoms, neuro-ascular anatomy, and the progressive nature of SM, a multidisci-linary decision was made to initiate medical therapy with clopi-ogrel (75 mg/d) and offer treatment of the carotid stenosis withndovascular stenting.

The patient was counseled regarding the risks, benefits, andlternatives to endovascular therapy and opted to proceed witharotid artery stenting. After obtaining appropriate informed con-ent, she was taken to the endovascular suite where the rightommon femoral artery was accessed under ultrasound guidancend local anesthesia with monitored light sedation to obtain neu-ologic examinations during the procedure as well as to maintain aatent airway. After sheath insertion and systemic administrationf heparin (0.8 mg/kg body weight), a marker pigtail catheter washen placed into the thoracic aorta, and an arch aortogram waserformed. The innominate artery and right common carotidrtery were selected using a JB-1 guide catheter (Cook Medicalnc, Bloomington, Ind) and glidewire (Terumo, Tokyo, Japan).he catheter and short sheath were then exchanged for a 7Finnacle destination sheath (Terumo), which was advanced to theid common carotid artery. Selective carotid and cerebral arterio-

rams were performed for preprocedural planning (Fig 3, A). Theatient was noted to have an isolated middle cerebral artery perfu-ion with no anterior cerebral artery filling. After adequate vesselizing was performed, a 4.5-mm Accunet embolic protection sys-em (Abbott, Abbott Park, Ill) was prepped and advanced to theevel of the distal internal carotid artery and deployed with goodpposition to the walls of the internal carotid artery. This wasonfirmed by angiogram. A 6- to 8-mm taper � 40-mm Acculinkarotid stent system (Abbott) was then prepped and advanced overhe wire and deployed from the internal carotid artery to theommon carotid artery as a primary stent deployment. Poststentngioplasty was then performed with a 4.5-mm balloon to 6 mmg pressure without any change to the patient’s hemodynamics.ngiogram at this point demonstrated brisk flow through thearotid bifurcation with a 10% residual stenosis (Fig 3, B). Therotection device was then retrieved and the completion angio-ram revealed improved flow through the middle cerebral artery

MCA). It also demonstrated reversal of anterior cross-filling in the

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JOURNAL OF VASCULAR SURGERYVolume 56, Number 2 Smolock et al 493

anterior cerebral artery (ACA) that was present prior. Of note, thisentire procedure was performed under TCD monitoring. We didnot appreciate any emboli during monitoring, and the embolicprotection device did not display any residual clot or thrombusafter removal.

Postprocedure, the patient was continued on clopidogrel. Shehad no postoperative complications and her neurologic symptoms

Fig 1. Computed tomography angiogram (CTA) demAxial image; B, coronal image also demonstrating mass

Fig 2. Carotid duplex (bilateral), B-mode, and colorartery.

resolved. The patient underwent a carotid duplex that demon- u

trated a patent stent and markedly decreased velocities fromaseline (Fig 4). She was discharged home on POD 2. At 18-onth follow-up, the patient has remained symptom free. Follow-p ultrasound examinations at 1, 3, 6, 9 months, 1 year, 18onths, and 2 years revealed stable carotid artery velocities sug-

estive of the minimal stenosis that was achieved immediatelyostprocedure. This was confirmed by CTA. She is scheduled to

ting cervical mass encasing the right carotid artery. A,and deviation of trachea to the left.

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DISCUSSION

Sclerosing or fibrosing mediastinitis is a rare, benigncondition caused by proliferation of fibrotic tissue in themediastinum, which is often idiopathic. However, manycases in the United States are thought to arise from aninappropriate immunologic response to histoplasmosis in-fection or previous thoracic malignancy.1,2 Described asfocal or diffuse, patients often present with signs and symp-toms of obstruction of mediastinal structures such as sup-erior vena cava, pulmonary veins or arteries, trachea, oresophagus (Table).1,2 Patients do not typically present withcarotid artery compression and neurologic symptoms. Di-agnosis of this syndrome usually is made by computedtomography prompted by pertinent history and physicalexamination. Long-term implications of this disease andhow best to follow it with diagnostic studies are not welldescribed in the literature except for case series with limitedfollow-up. Treatment of sclerosing mediastinitis is directedat any underlying infectious cause as well as control viasystemic corticosteroids, endovascular therapy for struc-tural obstructions, or surgical resection. However, surgicalresections have been met with poor results.3

Buoyed by advancements in endovascular therapy, ca-rotid artery angioplasty and stenting has increased in pop-ularity and utility, primarily for atherosclerotic occlusivedisease.4,5 However, neither an open nor endovascularapproach to treat the cervical carotid artery has been re-ported for this rare problem because fibrosing mediastinitis,as its name indicates, is generally confined to the mediasti-num. Interestingly in this case, the cervical carotid artery at thecarotid bifurcation was involved by direct extension of thefibrosing mass from the mediastinum extending up the right

Fig 3. Selective carotid angiogram. A, Preprocedure; B, post-stenting demonstrating minimal residual stenosis.

neck. This mass resulted in extrinsic compression of the com-H

on and internal carotid artery, and stenosis was confirmed byncreased velocities on carotid duplex evaluation.

All diagnostic tests, particularly ultrasound, demon-trated an extrinsic mass surrounding a carotid artery withmooth intima and nearly absent atherosclerotic disease.espite this, we chose to use an embolic protection deviceuring deployment of the carotid stent. We used a 6- to-mm taper �40-mm Acculink carotid stent system (Ab-ott) that allowed for approximately 15% vessel oversizings well as accounted for distal to proximal vessel size mis-atch. All other technical aspects of the procedure were

tandard for routine carotid artery stenting that is usuallyerformed for atherosclerotic disease or neointimal hyper-lasia (NIH).

Clinical decision making to treat a carotid lesion in thisase of posterior symptoms was complex. Specifically, theCD demonstrated a blunted right siphon signal and MCAaveform with major systolic upstroke delays. The left ACAelocity was higher than left MCA velocity, suggestingnterior cross-filling. Left posterior inferior cerebellar ar-ery displayed a high resistance waveform and the rightertebral artery reconstituted intracranially. Therefore, itas concluded that the posterior circulation might rely onosterior communicating artery flow from the internal ca-otid artery. A similar phenomenon has been reported asReversed Robin Hood Syndrome”6 We used this as a basiso treat a right carotid artery stenosis in order to alleviateosterior circulation symptoms and, in fact, the patient’symptoms improved postprocedure. She remains symptomree as her carotid remains stenosis free.

While there is some debate regarding the perioperativeorbidity and mortality advantages between carotid artery

tenting and carotid endarterectomy, the durability of ca-otid stenting is excellent for up to 4 years with results outo 10 years currently being evaluated.7 However, theseurability results are primarily in patients with atheroscle-osis or NIH and not perivascular fibrosis and/or extrinsicompression. At 2-year follow-up, the durability of carotidrtery stenting, as documented by serial ultrasound evalu-tion, for sclerosing mediastinitis is favorable in this anec-otal case. Such durable endovascular therapy allows forreatment of stenosis and subsequent relief of neurologicymptoms in a minimally invasive fashion to avoid a hostilenvironment for open surgical repair and the potential localomplications.

able. Clinical features of sclerosing mediastinitis

resenting signs or symptoms % reported

ough 41-45yspnea 14-67hest pain 21-27emoptysis 14-33

uperior vena cava syndrome 6-59ysphagia 2-14neumonia 23-27

oarseness 17

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CONCLUSIONS

Although a rare condition, sclerosing mediastinitis cancause extrinsic compression of both mediastinal and con-tiguous structures such as the cervical carotid artery. Du-plex examination can visualize this extrinsic compression aswell as the hemodynamic sequelae. Endovascular therapyprovides a novel and durable solution in the midterm to thisunusual clinical problem.

REFERENCES

1. Rossi SE, McAdams HP, Rosado-de-Christenson ML, Franks TJ, GalvinJR. Fibrosing mediastinitis. Radiographics 2001;21:737-57.

2. Loyd JE, Tillman BF, Atkinson JB, Des Prez RM. Mediastinal fibrosis

Fig 4. Carotid duplex (bilateral), B mode, and color floartery.

complicating histoplasmosis. Medicine (Baltimore) 1988;67:295-310. S

. Mole TM, Glover J, Sheppard MN. Sclerosing mediastinitis: a report on18 cases. Thorax 1995;50:280-3.

. Yadav JS, Wholey MH, Kuntz RE, Fayad P, Katzen BT, Mishkel GJ, et al.for the SAPPHIRE investigators. Protected carotid-artery stenting versusendarterectomy in high-risk patients. N Engl J Med 2004;351:1493-501.

. Hassoun HT, Malas MB, Freischlag JA. Secondary stroke prevention inthe era of carotid stenting: update on recent trials. Arch Surg 2010;145:928-35.

. Alexandrov AV, Sharma VK, Lao AY, Tsivgoulis G, Malkoff MD, Alex-androv AW. Reversed Robin Hood syndrome in acute ischemic strokepatients. Stroke 2007;38:3045-8.

. Brott TG, Hobson RW, Howard G, Roubin GS, Clark WM, Brooks W,et al. for the CREST investigators. Stenting versus endarterectomy fortreatment of carotid-artery stenosis. N Engl J Med 2010;363:11-23.

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ubmitted Oct 31, 2011; accepted Jan 23, 2012.