[6] Carotid Artery Disease Flashcards
What is carotid artery disease?
The build-up of atherosclerotic plaque in one or more common and internal carotid arteries, resulting in stenosis or occlusion
Is carotid artery disease always symptomatic?
No, the majority of cases are asymptomatic
What % of ischaemic strokes are due to carotid artery disease?
15%
How can carotid artery disease cause ischaemic strokes?
Plaque rupture and/or atheroembolism
What is the pathophysiology of carotid artery disease?
Same as for atheroma elsewhere, starting with fatty streak, accumulating a lipid core, and formation of a fibrous cap
What predisposes the atheromatous process specifically at the carotid artery?
The turbulent flow at the bifurcation of the carotid artery
What is carotid artery disease usually classified based on?
Classified radiologically by the degree of stenosis
What is considered to be mild carotid artery disease?
<50% reduction in diameter
What is considered to be moderate carotid artery disease?
50-69% reduction in diameter
What is considered to be severe carotid artery disease?
70-99% reduction in diameter
What is considered to be total occlusion in carotid artery disease?
100% reduction in diameter
What are the major risk factors for carotid artery disease?
>65 years Smoking Hypertension Hypercholesterolaemia Obesity Diabetes mellitus History of cardiovascular disease Family history of cardiovascular disease
How does carotid artery disease present?
It will often be asymptomatic, however may present as a focal neurological deficit
How can carotid artery disease lead to focal neurological disease?
Can lead to transient ischaemic attack or stroke
How long does a TIA last before resolution?
24 hours
What is amaurosis fugax?
Transient visual loss that may be associated with TIA
How long does a stroke last?
24 hours or more without full resolution
How are strokes classified?
Oxford Stroke (Bamford) Classification
What is the Oxford Stroke Classification based on?
The stroke symptoms in relation to the arterial regions involved
What may be found on examination in carotid artery disease?
A carotid bruit may be auscultated in the neck
What proportion of carotid bruits auscultated in the neck are associated with carotid stenosis?
About half
Why is carotid stenosis likely to be asymptomatic if unilateral (apart from clinical features of stroke)?
Due to collateral supply from the contralateral internal carotid artery and vertebral arteries, via the Circle of Willis
What are the different classifications of stroke according to the Oxford Stroke Classification?
Total Anterior Circulation Stoke (TCAS)
Partial Anterior Circulation Stroke (PACS)
Lacunar Stroke (LACS)
Posterior Circulation Stroke (POCS)
What % of strokes are total anterior circulation strokes?
20%