Uncommon Disorders Affecting the Carotid Arteries Lana Schumacher, M.D.

Surgery Resident 5/22/06

Uncommon Carotid Disorders

• Carotid Kinks and Coils • Carotid Body Tumors • Carotid Sinus Syndrome • Carotid Dissection • Vasculitis • Moyamoya

Carotid Artery Kinks & Coils

• First described by anatomists in 1700s • Fatal hemorrhage after injury to tortuous carotid arteries after tonsillectomy described in 1900s • Most are incidental findings with no clinical significance • Some produce cerebrovascular symptoms due to angulation • Excessively long Carotid

Carotid Artery Kinks & Coils

• Congenital (usually bilateral ~50%) – Faulty descent of heart and great vessels – Excessive lengthening of carotid as cervical spine elongates • Aquired (usually unilateral) – Carotid elongates with age – Elderly with atherosclerosis, thinning of media, fragmenting of elastic lamina, plaques that fix vessel – Fascial band • ICA is usually affected – S shape, single, double complete loops have all been described – Acute angle/kinks often are associated with plaque or stenosis • Kinks - Women:Men - 4:1 • Incidence?

Carotid Artery Kinks & Coils – Clinical Presentation

• Coils and loops – don’t obstruct therefore usually asymptomatic • Kinks – luminal narrowing, intimal ulceration, embolization – TIAs, strokes, amaurosis fugax – Symptoms can be caused by head turning • Diagnose – four-vessel cerebral arteriography – Perform in position that produces symptoms

Treatment of Coils & Kinks

• Tethering – inadequate • Long-Patch Angioplasty • Resection and reanastomosis of portion of common carotid

Treatment of Coils & Kinks

•ICA resection and reanastomosis •ICA resection and Saphenous Vein interposition •ICA reimplantaion to CCA •Results – 80% asymptomatic, 5% perioperative stroke and mortality rate

Carotid Body Tumors

• Carotid Body – First described in 1743 by Von Haller – Chemoreceptor at the bifurcation of the CCA in the posterior medial adventitia • Responds to hypoxia, hypercapnia, acidosis • Increases RR, TV, HR, BP – Blood supply from ECA – Neural crest cells from the 3 rd Branchial arch – Tumors are “Paraganglionomas” or “Chemodectomas”

Carotid Body Tumors

• Characteristics – Highly vascular, blood supply from ECA – Very rare, usually 5 th decade of life – Classified as Chromaffin positive (catecholamines) and non chromaffin cells – 5% are functional causing Htn – Sporadic – 5% bilateral – Familial – autosomal dominant, 32% bilateral – Malignancy rates 2-50% • metastatic rate 5% - LN, kidney, thyroid, pancreas, lungs, brain bone brachial plexus, abdomen, breast

Carotid Body Tumors

• • •

Group I

-relatively small tumors, minimally attached to the carotid vessels; surgical excision is not difficult

Group II

- larger, moderate attachments; resectable but many require a temporary intraluminal carotid shunt

Group III

grafting - very large neoplasms encasing the carotid arteries;often require arterial resection and * Well circumscribed, rubbery, reddish brown

Clinical presentation and diagnosis

• Most common presentation - Painless swelling in neck at angle of mandible •Neck or ear pain, local tenderness, hoarse, dysphasia, tinnitus •If functional – symptoms of dizziness, flushing, palpitations, tachycardia, arrhythmias, headache, diaphoresis, photophobia •Bruit if tumor is impinging the artery •Diagnosis – •Duplex scan – highly vascular mass at bifurcation •Angiography – gold standard •CTA, MRA – size and extent of tumor •Avoid FNA – massive hemorrhage, pseudoaneurysm, carotid thrombosis

Treatment of Carotid Body Tumors

• Complete surgical excision • Radiation – – results unsatisfactory – Usually for local control of residual or recurrent disease • Chemotherapy – no role • Large tumors – Remove from inferior to cephalad – Sublux TMJ, divide digastric – Transmural invasion - resection of artery, saphenous vein graft, shunts • Incidence of cranial nerve injury 20-40% • Stroke rates ~5% • 6% develop recurrence after complete resection

Carotid Sinus Syndrome (CSS)

• Carotid Sinus – Located at distal end of CCA at bifurcation – Area of dilation – tunica media is thinner & adventitia is thicker – Baroreceptor • Increase P – reflex bradycardia, decrease BP

Carotid Sinus Syndrome (CSS)

• Carotid Sinus Syndrome – Carotid sinus hypersensitivity leading to syncope – Sudden onset of bradycardia & hypotension – Pathophysiology is unknown – Occurs in elderly, M>W – Associated with atherosclerosis, DM, Htn, CAD – Cause of <1% of syncope – Syncope precipitated by head movement in ½ of patients • Treatment – Discontinue antihypertensives if possible – Carotid body denervation is not recommended – Cardiac pacemakers

Carotid Artery Dissection

• Dissection – intimal disruption, extravasation of blood into arterial wall • Stenosis, occlusion, aneurysm (late complication) • Blunt Trauma – MVA, fist fights, falls, direct trauma, hanging – Hyperextension, rotation – stretching of ICA against transverse processes of C2-3 • Spontaneous dissections – Marfans, FMD

Mechanisms of Injury

• • • Tear is usually 2-4 cm from the bifurcation – stops at entrance into the carotid canal Hyperextension & rotation of head – Compression by first cervical vertebrae, TP of C2 3 Extreme flexion – Compression of mandible and TP C2-3 – Fracture or posterior dislocation of mandible

Diagnosis & Treatment

• • •

Symptoms – pain, unilateral headache (anterior head, orbit, periorbital), neck pain

– TIAs, stroke in 1/3-3/4 – Oculosympathetic paresis – occurs minutes to days after onset of headache • Incomplete Horner’s syndrome (facial sweating unaffected) – Palsies – slurred speech, dysphagia

Diagnosis – Duplex or angiography Treatment

– Anticoagulate – 3-4 months, then antiplatelet 3-4 months • Repeat angiography in 2 months – Surgery if medical therapy fails – thrombectomy, intraluminal dilation, endarterectomy, intimectomy, graft interposition – Carotid ligation if recurrent emolization

• Radiation-Induced Carotid Arteritis and Stenosis Two patterns of disease

1. Luminal occlusion – 7-24 years after radiation – Pathophysiology – plaque-like thickening of intima, fibrosis of media and adventitia – Can lead to accelerated athlerosclerosis 2. Arterial Disruption – Usually after primary resection of tumor followed by radiation – Associated with tissue infection/wound breakdown

• •

Radiation-Induced Carotid Arteritis and Stenosis – When to Operate?

– Transmural radiation damage Recommend bypass graft of diseased segments – Late presentation – usually accelerated atherosclerosis Endarterectomy – technically more difficult due to periarterial fibrosis and strong adherence of plaque to vessel wall – Sometimes segmental resection and reconstruction is required due to wall attenuation  Important to consider life expectancy, healing of irradiated tissue/infection

• Radiation-Induced Carotid Arteritis and Stenosis – When to Operate?

Carotid artery rupture

– Poor prognosis – Present with sentinel bleed then exsanguinating hemorrhage – Prompt surgical exploration, carotid ligation or EC-IC bypass

Vasculitis

• Inflammatory process resulting in necrosis of structural elements of vessel wall • Obliteration of lumen leads to ischemia • Variable course and variable presentation • No definitive lab tests or clinical signs • Primary or secondary due to underslying disease • Women usually > men 2:1 • Vasculitis cannot be excluded based on negative angiogram

Giant Cell Arteritis

• Affects medium and large arteries • Elderly women • Usually presents as temporal arteritis • Can affect aortic arch and extracranial carotid arteries • findings include disruptions of elastic lamina and media, granulomatous degeneration • Lesions are short and segmental with normal artery between lesions

Temporal Arteritis

• Involves branches of external carotid artery – especially superficial temporal arteries, posterior ciliary, ophtalmic arteries • Flu-like syndrome, low-grade fever, Headache, scalp tenderness, jaw claudication, visual changes (amaursosis fugax, diplopia, permanent visual loss) • ESR may be elevated • vessels can be tender to palpation, cordlike and difficult to compress • Sudden and complete visual loss in 62% – Loss of blood supply to ophthalmic artery – Can progress to blindness in less than 24 hrs

Temporal Arteritis

• Diagnosis – 4-7 cm biopsy – Biopsy contralateral artery if first biopsy is negative – (14% incidence of positive contralateral biopsies) • Treatment – – “medical emergency” – start steroids immediately – Prognosis is good if treated expeditiously and does not influence life expectancy

Takayasu’s Arteritis

• “Pulseless Disease” • “Obliterative brachiocephalic Arteries” – Margagni (1761) • “autopsy findings in a 40 yo F with absent radial pulses, thickened proximal aorta, lower thoracic aortic stenosis, cardiac hyperthrophy and pulmonary edema – Takayasu (1908) • “young Japanese woman with progressive visual loss, vertigo, syncope, conjunctival injection, retinal arteriovenous anastomoses, alopecia” • Occurs in all races and age groups, women 2 nd -3 rd decades • Involves the aortic arch and great vessels • Cerebral ischemia is the most life-threatening complications – Can involve more distal aortic segments as well as pulmonary and coronary arteries

Classifications of Takayasu’s

Type I

•20-40% •Arch + great vessels •Cerebrovascular insufficienty, visual abnormalities

Type II

•20-40% •Mid Aortic – involving distal thoracic and abdominal •Mesenteric ischemia, renal artery stenosis

Type III

•50-65% •Both Arch and abdominal aorta •Cerebrovascular, lower extremity symptoms, htn

Type IV

•10% •Pulmonary Arteries

Clinical Presentation

• Phase I – Prodrome of “malaise, anorexia, fatigue, weight loss, anemia, myalgias, fevers, night sweats” • Phase II – Inflammation of blood vessels – discomfort • Phase III – Symptoms of ischemia depending on location • TIAs, visual impairment – diplopia, amaurosis fugax, blurred vission, stroke, effort fatigue of upper extremities • Renovascular hypertension, mesenteric ischemia, lower extremity insufficiency • Pulmonary hypertension, dyspnea on exertion, pleuritic chest pain – Arterial stenosis, embolization, occlusion, aneurysm

Diagnosis of Takayasu’s • High index of suspicion • ESR elevated in inflammatory phase • Angiography

– Stenosis, occlusion of proximal extracranial cerebral arteries

Treatment of Takayasu’s

• Course is unpredictable – Prognosis can be dependent on the presence of complications and severity of disease – Death usually due to CHF, stroke, MI, Renal failue – 5 year survival rate 55-98% • Steroids and anti-inflammatories – high dose, then taper – may be on steroids for many years • Cyclophosphamide – if no response to steroid after 3 months • Long-term anticoagulation

Surgery for Takayasu’s

• Surgery required in up to 1/3 of patients with chronic advanced Takayasu’s • Surgery should be delayed past active phase • Transmural disease with all layers – endarterectomy or patch angioplasty is not recommended – Interposition graft • Multiple operations are required • Close postoperative surveillance due to frequent development of anastomotic stenosis in first 1-2 years

Moyamoya

• Rare cerebrovacular disorder leading to progressive stenosis in the arteries of the circle of Willis • Ischemic strokes in children • Hemorrhages in adults • Described by Takeuchi & Shimizu in 1957 – “bilateral hypogenesis of the ICAs” – Moyamoya = “puff of smoke”

Moyamoya

• Cause is unknown • Episode of infection/URI is frequently antecedent • Does not affect large vessels • Begins with carotid artery in cavernous sinus and progresses • Familial cases and higher incidence in Down Syndrome

Presentation of Moyamoya

• Biphasic age – 1 st & 4 th decades • Female to male 1:5 • Children – ischemic sx, TIAs, stroke – Induced by crying, coughing, straining, seizures – Mortality 4% • Adults – hemorrhage usually into ventricles, thalamus, basal ganglia – Worse prognosis - Mortality 10%

Diagnosis of Moyamoya

• • • • • • • CT or MR – dilated abnormal vessels in basal ganglia, thalamus, occlusion/narrowing of circle of Willis, infarct or hemorrhages

stage I

-stenosis of the carotid artery at its suprasellar portion, usually ccurring bilaterally.

stage II

, narrow carotid, and moyamoya vessels at the base of the brain.

stage III

, abnormal moyamoya vessels become more prominent as major arteries in the anterior circulation, severely stenotic or occluded; at this stage, the diagnosis is usually confirmed

stage IV

, the moyamoya vessels extend to all components of the circle of Willis, including the posterior cerebral arteries.

stage V stage VI

, the moyamoya vessels begin to diminish. , they disappear completely and cerebral hemisphere receives blood through abnormal EC IC anastomoses •

Treatment of Moyamoya

• Superficial temporal artery to middle cerebral artery anastomosis • “Encephaloduroarteriosynangiosis” – suturing of superficial temporal artery along the longitudinal dural defect to approximate the artery to the brain surface • “Encephalomyosynangiosis” – suture temporalis muscle to surgical dural defects – Indirect anastomosic procedures to allow neovasculariztion from extracranial arterial and soft tissue systems to the ischemic brain