A transient ischaemic attack (TIA), as the name suggests, is a brief period of neurological deficit due to a vascular cause, typically lasting less than an hour.

The original definition of a TIA was time-based: a sudden onset of a focal neurologic symptom and/or sign lasting less than 24 hours, brought on by a transient decrease in blood flow. However, this has now changed as it is recognised that even short periods of ischaemia can result in pathological changes to the brain. Therefore, a new 'tissue-based' definition is now used: a transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischaemia, without acute infarction. #link13

Patients often use the term 'mini-stroke' for TIAs.


  • Incidence: 230.00 cases per 100,000 person-years
  • Peak incidence: 70+ years
  • Sex ratio: more common in males 1.3:1
<1 1-5 6+ 16+ 30+ 40+ 50+ 60+ 70+ 80+

Clinical features

The clinical features are similar to those of a stroke, i.e. sudden onset, focal neurological deficit but, rather than persisting, the features resolve, typically within 1 hour.

Possible features include
  • unilateral weakness or sensory loss.
  • aphasia or dysarthria
  • ataxia, vertigo, or loss of balance
  • visual problems
    • sudden transient loss of vision in one eye (amaurosis fugax)
    • diplopia
    • homonymous hemianopia


Neuroimaging #link15
  • NICE recommend that CT brains should not be done 'unless there is clinical suspicion of an alternative diagnosis that CT could detect'
  • MRI (including diffusion-weighted and blood-sensitive sequences) is preferred to determine the territory of ischaemia, or to detect haemorrhage or alternative pathologies
    • it should be done on the same day as the specialist assessment if possible

Carotid imaging
  • atherosclerosis in the carotid artery may be a source of emboli in some patients
  • all patients should therefore have an urgent carotid doppler unless they are not a candidate for carotid endarterectomy


The ABCD2 prognostic score has previously been used to risk stratify patients who present with a suspected TIA. However, data from studies have suggested it performs poorly and it is therefore no longer recommended by NICE Clinical Knowledge Summaries. Instead, NICE recommend:

Immediate antithrombotic therapy: #link14
  • give aspirin 300 mg immediately, unless:
    • 1. the patient has a bleeding disorder or is taking an anticoagulant (needs immediate admission for imaging to exclude a haemorrhage)
    • 2. the patient is already taking low-dose aspirin regularly: continue the current dose of aspirin until reviewed by a specialist
    • 3. Aspirin is contraindicated: discuss management urgently with the specialist team

Specialist review
  • if the patient has had more than 1 TIA ('crescendo TIA') or has a suspected cardioembolic source or severe carotid stenosis:
    • discuss the need for admission or observation urgently with a stroke specialist
  • If the patient has had a suspected TIA in the last 7 days:
    • arrange urgent assessment (within 24 hours) by a specialist stroke physician
  • if the patient has had a suspected TIA which occurred more than a week previously:
    • refer for specialist assessment as soon as possible within 7 days

Advise the person not to drive until they have been seen by a specialist.

Further management

Secondary prevention #link16
  • antiplatelet therapy to follow on from initial aspirin therapy
    • clopidogrel is recommended first-line (as for patients who've had a stroke)
    • aspirin + dipyridamole should be given to patients who cannot tolerate clopidogrel
  • lipid modification
    • high-intensity statin (such as atorvastatin 20–80 mg daily) - the aim of statin therapy is to reduce non-HDL cholesterol by more than 40%

With regards to carotid artery endarterectomy: #link17
  • recommend if the patient has suffered stroke or TIA in the carotid territory and is not severely disabled
  • should only be considered if
    • carotid stenosis > 70% according European Carotid Surgery Trialists' Collaborative Group criteria or
    • > 50% according to North American Symptomatic Carotid Endarterectomy Trial criteria