Transient Ischaemic Attack

Question 1

What is a TIA

Answer 1

Ischaemic neurological event with symptoms lasting < 24h

Without intervention 1 in 12 patient go on to have as stroke within a week

Question 2

What are signs of TIA?

Answer 2

Specific to the arterial territory invovled
Amaruosis fugal occurs when he retinal artery is occluded, c causing unilateral progressive vision loss like a curtain descending

Global events (syncope dizziness) are NOT TYPICAL of TIAs

Attacks may be single or many
Multiple highly stereotyped attacks (crescendo TIAs) suggest intracranial stenosis (Superior division of MCA commonly)

Question 3

What are causes of TIA?

Answer 3

Atherothromboembolism from the carotid
- listen for bruits

Cardioembolism - mural thrombus post MI or in AF, valve disease or prosthetic valve

Hyperviscousity: polycythamia, sickle cell disease, myeloma

Vasculitis - rare, non embolic cause or TIA symptoms - cranial arteritis, SLE, syphilis

Question 4

What are differentials for TIA?

Answer 4

Hypoglycaemia, migraine aura, focal epilepsy, hyperventilation, retinal bleeds

Mimics:
Malignant HTN
Intracranial SOL

Question 5

What is used to help define risk of stroke in TIA patients?

Answer 5

ABCD2 score

Age >/= 60 1pt
BP 140/90 + 1pt
Clinical features:
 - unilateral weakness 2pt
- speech disturbance without weakness 1pt
Duration of symptoms:
- symptoms lasting > 1 h 2 points
- symptoms lasting 10-59 mins 1 point
Diabetes 1 pt

4+ indicates patient is high risk of early stroke and must be assess within 24h by specialist

6+ strongly predicts stroke

Other factors:
AF
>1 TIA in a week
TIA while anticoagulated

Question 6

What is management for TIA?

Answer 6

Immediate antithormbotic therapy:
Aspirin 300mg immediately unless:
1. bleeding disorder or anti coagulated
2. patient is already taking low dose aspirin
Aspirin is contraindicated

Continue for 2wks then switch to clopidogrel OD

Anticoagulation if cardiac source of emboli

Control CVS risk factors: optimise BP, hyperlipidaemia, DM, stop smoking

Carotid endarterectomy:
Perform within 2 wks of first presentation if stenosis and operative risk is acceptable
Do not stop aspirin pre-op

Question 7

Driving post TIA?

Answer 7

Prohibited for at least 1 month

do not drive until specialist review.