Carotid Artery Disease Flashcards
What does carotid artery disease refer to?
Build-up of atherosclerotic plaque in one or both common and internal carotid arteries leading to stenosis or occlusion.
Majority are asymptomatic, but 10-15% go on to have ischaemic strokes
Pathophysiology
Fatty streak -> accumulation to a lipid core + fibrous cap
The turbulent flow at the bifurcation of the carotid artery predisposed to this process specifically at this region.
How can carotid artery disease be classified?
Radiologically by degree of stenosis
Mild - <50% diameter reduction
Moderate - 50-69%
Severe - 70-99%
Total occlusion - 100%
RF
Age >65
Smoking
HTN
Hypercholesterolaemia
Obesity
DM
Hx of CVD
FH of CVD
Clincal features
Usually asymptomatic but can present with complications such as…
TIA
Stroke
Examination
Oxford Stroke Bamford Classification
You might hear a carotid bruit when auscultating over carotid
They are very much likely to be asymptomatic if it is unilateral due to collateral supply from contralateral IC and vertebral arteries via Circle of Willis
Dx
Carotid dissection (patients are more likely younger and underlying connective tissue disease)
Thrombotic occlusion of carotid (presents exactly the same)
Fibromuscular dysplasia (hypertrophy of vessel wall affecting young <50y females)
Vasculitis like GCA and Takayasu’s
Hypoglycaemia
Subdural haematoma
Todd’s paresis
Space occupying lesion
Venous sinus thrombosis
Post-ictal state
MS
Initial investigations
Any patient suspected of ischaemic or haemorrhagic stroke should have urgent non-contrast CT head scan for evidence of infarction (although US doppler is readily used first but only if no stroke/TIA)
Bloods with FBC, U&Es, clotting, lipid profile and glucose
ECG (especially to check for AF)
What investigation should be done if thrombectomy is considered in patients with evidence of ischaemia?
CT head contrast angiography
Follow-up investigations
Once diagnosis of stroke or TIA is made…
Screen carotid arteries for disease and can be done by Duplex ultrasound scans.
This gives a good estimate of degree of stenosis
A CT angiography might be done subsequently to give a more accurate assessment of the diseased portion of the vessels prior to any potential surgery
Acute management
High flow oxygen + blood glucose optimised
Swallowing screen assessment should be done as well.
Ischaemic stroke -> IV alteplase (r-tPA) if admitted within 4.5h of symptom onset and meet inclusion criteria + 300mg aspirin orally.
Haemorrhagic stroke -> correction of any coagulopathy and referral to neurosurgery for potential clot evacuation.
When is thrombectomy indicated?
In patients with confirmed acute ischaemic stroke and confirmed occlusion of proximal anterior circulation on angiography.
IV thrombolysis is indicated as well for this.
Long term management of known stroke or TIA
Anti-platelet therapy 300mg OD for 2 weeks then clopidogrel 75mg OD
Statin 80mg atorvastatin
Aggressive management of hypertension and/or diabetes mellitus (ACEi)
Smoking cessation
Regular cardiovascualr exercise and active lifestyle with weight loss
Referral to speech and language therapy if needed or physio if needed
When is carotid endarterectomy indicated?
Patients with acute non-disabling stroke or TIA who have symptomatic carotid stenosis between 50-99%
They should be referred for assessment for a CEA
Explain CEA
Removes the atheroma and associated damaged tunica intima
This reduces the risk of future strokes or TIAs.
Risks of CEA surgery
Stroke
Nerve damage to hypoglossal
Nerve damage to CN IX
Nerve damage to CN X
MI
Local bleed
Infection
