Stroke symposium

Question 1

Risk factors for endothelial injury

Answer 1

• Hyperlipidaemia
• Smoking
• Hypertension
• Homocysteine [from meat]
• Haemodynamic factors
• Immune reactions
• Toxin and viruses

Question 2

Stroke pathology [atherosclerosis formation]

Answer 2

1. Endothelial injury
   - Causes increased vascular permeability –> Infiltration of leucocytes—> Adhesion of leucocytes + monocytes
2. Accumulation of lipoproteins
   - LDL and oxidised LP
3. Monocytes migrate into the intima and become macrophages. Smooth muscle also migrates into intima
   - Digest oxidised LDL–> forms foam cells
4. Smooth muscle proliferates.
5. Collagen, other ECM components deposisted into intima
6. Lumen narrows–> Fibrofatty atheroma [formed from EC lipids] form

Question 3

Vascular risk factors for stroke

Answer 3

Hypertension

Hyperlipidaemia

High LDL–> oxidised

Diabetes

Smoking

Question 4

ACA infarct presentation

Answer 4

Mainly affects the contralateral lower limb

Question 5

Left MCA infract presentation

Answer 5

Dysphasia

Right sided weakness/numbness

Question 6

Right MCA infarct presentation

Answer 6

Neglect [lack of awareness]

Left sided-weakness/numbness

Question 7

Brainstem infarct presentation

Answer 7

Diplopia [double vision]

Visual field defect

Facial weakness

Contralateral limb weakness

In-cordination

Question 8

Critical ischaemia

Answer 8

When blood flow is <20ml/100g/min

• Electrical function stops
• Neurones are still alive but for a limited time
• Can be reversed

When blood flow is <10ml/100g/min

• Neurones dies
• Irreversible

Measured via CT perfusion image

Question 9

Thrombolysis

Answer 9

Method of breaking clots
- Treatment of stroke

Efficacy dependant on:

• Time [quicker=better]
• Length of clot [longer = less efficacy]

Question 10

Watershed infarct

Answer 10

Infarct in border zones of tissues supplied by middle and anterior cerebral arteries.

Question 11

Anti platelet agents

Answer 11

Aspirin–> Inhibits COX

Clopidogrel–> Blocks ADP binding site

Dipyridamole—> Inhibits cAMP breakdown

Question 12

Carotid stenosis

Answer 12

Narrowing of carotid artery due to atherosclerosis

Thrombus can form and dislodge—> cerebral artery

Question 13

Ischaemic infarct classification

Answer 13

TOAST

Large artery atherosclerosis

Cardioembolism

Small vessel occlusion

Stroke of undetermined etiology

Stroke of other determined origin

Question 14

Carotid stenosis treatment

Answer 14

Carotid endarterectomy

• Incision is made to open the artery
• Plaque is removed
• Artery is repaired