Transient
ischaemic attacksA TIA is a marker of vascular disease and indicates that the patient is at risk from a serious vascular event: about 15% of patients who suffer a stroke have had previous TIA's. 3% will suffer MI in the following year. The overall incidence of a major vascular event in the following year is 9%.
Diagnosis is mainly from history:
- 80% affect the carotid territory and may present with unilateral paresis, sensosry loss, aphasia or monocular visual loss.
- Vertibrobasilar TIA's present with bilateral/alternating weakness/sensory loss, bilateral blindness, or two or more of vertigo, diplopia, dysphagia, dysarthria, ataxia .
Most patients will benefit from aspirin, a few from warfarin and very few from surgery. The risk of catastrophic events is greatest in the first few weeks, so referral should be considered early.
Investigations
Baseline:
- FBC
- ESR
- Glucose
- Cholesterol
- VDRL
- ECG
Consider:
- CXR
- Echocardiography
- CT scan
- MRI scan
- Carotid angiography
Management
Management of risk factors
- Stroke
- Hypertension
- Smoking
- Hyperlipidaemia
- Aspirin: 300mg stat, 75-150mg/day indefinitely.
- Warfarin
Definitive surgical management
Carotid artery surgery
Effectiveness of various interventions in patients who have had a TIA
| Intervention | No preventing 1stroke/yr* | Reduction in stroke incidence |
|---|---|---|
| Aspirin | 67 | 3% |
| BP treatment | 44 | 2% |
| Warfarin for AF (less than 80 yrs) | 30 | 5% |
| Carotid endarterectomy | 20 | less than 1% |
(ie: no of patients who need to be treated for 1 year)
Reference: Prescribers Journal 1996 Vol36 No1