Extracranial Vascular Disease

GOALS:

1. Identify patients with significant extracranial vascular disease.
2. Evaluate risk factors.
3. Determine degree of stenosis.

PERTINENT HISTORY
Any of the following raise the possibility of EVD:

1. Carotid Territory Symptoms - unilateral motor or sensory loss, facial droop, aphasia.
2. Unilateral visual loss - not field cut.
3. Asymptomatic neck bruit.
4. Vertebrobasilar symptoms - cranial nerve problems (e.g. diplopia, field cut, dysarthria, transient cortical blindness), alternating monoparesis, gait disturbance, drop attacks.

PHYSICAL EXAMINATION:

1. Palpation of brachial, radial, carotid and temporal pulses, bilateral brachial pressures (sitting and lying if indicated).
2. Auscultation of heart and neck for bruits.
3. Neurological Examination.
4. Fundoscopy (Hollenhorst plaque)

DIFFERENTIAL DIAGNOSIS:

Cerebral ischemia from other sources - arrhythmia, cardiac emboli, intracranial lesions, postural hypotension.

DIAGNOSTIC TESTS

1. If extracranial vascular disease is present it can be quantified by duplex ultrasound - this should be done in preference to other tests, i.e. MR angiography, venous DSA as more cost effective.
2. Brain imaging - CT or MRI should be reserved for patients suspected of having an intracranial lesion - it is not required for every patient with TIA?s or asymptomatic bruit.
3. Holter Monitor - only when arrhythmia?s are suspected and in the absence of a positive
4. duplex.
5. Echocardiogram - transthoracic is helpful only to confirm a large atrium and useful clinically only when no carotid source is suspected. Transesophageal may be useful in evaluating the thoracic aorta as a source of emboli.

MANAGEMENT:

1. If ICA stenosis > 70% is detected by duplex, the patient should be considered as an operative candidate (i.e. for CEA). Therefore REFER TO A VASCULAR OR NEUROVASCULAR SURGEON
2. ICA stenosis 30-705 - consider follow up duplex in 6-12 months in asymptomatic patients.
3. Symptomatic patients ICA stenosis < 70% - look for other causes for symptoms (see above) if stenosis 50-70% consider surgical evaluation.
4. Bilateral vertebral disease with vertebrobasilar symptoms should be evaluated by neurologist or surgeon for possible surgical therapy.
5. Antiplatelet agents for patients with symptoms and < 50% stenosis or 50-70% stenosis, questionable for thoracic aortic disease.
6. Anticoagulants for patient with cardiac source of emboli.

 

MANAGEMENT ALGORITHM

EXTRACRANIAL VASCULAR DISEASE
Duplex Ultrasound

Less than 50% Carotid Stenosis

Asymptomatic - no further workup
Symptomatic - look for other causes of symptoms

50-70% Carotid Stenosis

Asymptomatic - follow up duplex in 6-12 months
Symptomatic

• Begin antiplatelet therapy
• Evaluate cardiac or intracranial source of symptoms
• If no good alternative source of symptoms consider referral for endarterectomy

> 70% Stenosis

Asymptomatic - refer patients with reasonable life expectancy (3-5 years) for surgical evaluation
Symptomatic - refer all patients for surgical evaluation

Subclavian Steal/Vertebral Disease

Asymptomatic - treat on basis on carotid lesion
Symptomatic (CNS or ARM) - refer for surgical evaluation