Stroke Flashcards
Give a definition of a TIA
A neurological deficit of presumed vascular origin, lasting for greater than 24 hours
What are the different types of strokes which can occur?
Haemorrhagic
Ischaemic
Subarachnoid haemorrhage
What artery supplies the anterior circulation?
Internal carotid artery
Which artery supplies the posterior circulation?
Vertebral arteries plus branches
Give some common causes for ischaemic stroke
Atherosclerosis Arteriosclerosis Aortic dissection Cardioembolism e.g. AF, cardiac thrombus Vasculitis Genetic causes
What types of vasculitis can cause stroke?
Antiphospholipid syndrome
Thrombophilia
Give some genetic causes which predispose to stroke
CADASIL
- Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy
Hyperhomocysteinaemia
Fabry’s disease
What cause of stroke is particularly more common in smokers?
Carotid stenosis
Give some of the common causes for haemorrhagic stroke
Chronic hypertension Cerebral amyloid angiopathy Anticoagulants Anteriovenous malformations Caveromas Tumours
What are the four main mechanisms by which strokes can occur?
Large vessel infarction
Cardio embolism
Small vessel disease
Low flow
Describe the pathophysiology for large vessel disease
Atherosclerosis and a ruptured plaque with thrombosis leads to the occlusion of an artery via a clot/multiple clots
Describe the pathophysiology for a cardio embolism causing a stroke
AF and PFO predispose due to blood stasis, leading to an increased coagulability
Describe the pathophysiology for small vessel disease infarctions
There is the occlusions of multiple thin arterioles leading to lacunar strokes. These are seen in the basal ganglia, thalamus, internal capsule and the pons
Describe the pathophysiology for low flow infarctions
These occur with sepsis, hypotension and postoperatively. Lead to a watershed infarct at the borders between arteries e.g. between ACA and MCA or MCA and PCA.
What signs would give an indication of an anterior circulation stroke?
Hemiparesis of face/trunk/arm/leg
Hemisensory loss
Homonymous Hemianopia
Dysphagia (L frontal/parietal/temporal lobe is affected)
Neglect/extinction if right parietal cortex is affected
What signs would give an indication of a posterior circulation stroke?
Hemianopia on contralateral side Vertigo Diplopia Weakness, usually on contralateral side Hicoughs Dysarthria Ataxia Facial weakness (same side) Limb weakness (opposite side) Cranial nerve palsies Horner's syndrome
What are the stroke classification systems used?
Bamford and Oxford
