- MRI (on the same day) to determine the territory of ischaemia or detect haemorrhage
- Urgent carotid imaging (if considered a candidate for carotid endarterectomy)
Transient Ischaemic Attack (TIA)
National Clinical Guideline for Stroke 2023 Edition.
NICE Guideline [NG128] Stroke and transient ischaemic attack in over 16s: diagnosis and initial management. Last updated: Apr 2022
TO BE REVIEWED!
Diagnosis
Assessment and Diagnosis
Primary Care / Emergency Department
Immediate steps if TIA is suspected:
- Exclude hypoglycaemia
- Offer aspirin 300mg immediately unless contraindicated (e.g., patients on anticoagulants)
- Refer within 24 hours to acute stroke unit / specialist
Do NOT use the ABCD2 score to stratify risk of TIA / inform urgency of referral / guide treatment
Specialist Care (Stroke Unit)
If the patient takes anticoagulant / has a bleeding disorder → urgent non-contrast head CT to exclude haemorrhage
- Otherwise, NICE recommends NOT to routinely offer CT brain unless there is clinical suspicion of an alternative diagnosis that CT could detect
Management
There are 3 aspects of TIA management:
1. Antithrombotic Therapy
Every patient with TIA needs some form of antithrombotic therapy to prevent further cerebrovascular events, but the choice depends on whether the patient has atrial fibrillation or not.
TIA with no Atrial Fibrillation
Antiplatelets are the choice of antithrombotic therapy in the absence of AF (i.e., for thrombotic TIA)
There are 2 regimens recommended, depending on the patient’s bleeding risk.
| Bleeding risk | Antiplatelet regimen |
|---|---|
| Low bleeding risk (most cases) |
Alternative to clopidogrel is ticagrelor (loading dose: 180mg, maintenance dose: 90mg BD) |
| High bleeding risk |
|
Note that DAPT is used in TIA but not in ischaemic stroke. This is due to the higher risk of haemorrhagic transformation in ischaemic stroke, which outweighs the potential benefits of DAPT.
TIA with Atrial Fibrillation
Offer a head CT to exclude intracerebral haemorrhage, then offer anticoagulation
- 1st line for most patients: DOAC (e.g. apixaban)
- 1st line in valvular AF: warfarin
Note the timing to start anticoagulation in TIA is different from that in ischaemic stroke:
- In ischaemic stroke with AF (i.e., embolic stroke), anticoagulation is only started after 5-14 days, with only aspirin 300mg being given during those 5-14 days
- In TIA with AF (i.e., embolic TIA), anticoagulation can be started immediately, once intracerebral haemorrhage has been excluded
This difference in timing reflects the balance of benefits and bleeding risk in the presence of established infarction (stroke) vs TIA. Anticoagulants carry a much higher risk of intracerebral haemorrhage than antiplatelets.
In ischemic stroke with AF, there is a significant risk of hemorrhagic transformation in the infarcted brain tissue if anticoagulation is started immediately. Therefore, anticoagulation is typically delayed for about 5-14 days, while aspirin 300 mg is given in this period to prevent early recurrent ischemia.
In TIA with AF, there is no established infarcted tissue and thus essentially no risk of hemorrhagic transformation. Once intracerebral haemorrhage is excluded by imaging, anticoagulation can be started immediately to provide early secondary stroke prevention.
But ultimately, for both ischaemic stroke and TIA patients with AF, long-term anticoagulation (not antiplatelet therapy) is required for effective stroke prevention.
2. Secondary Prevention
All patients should receive the following:
- Lifestyle advice
- High-intensity stain
- BP-lowering therapy
3. Carotid Intervention
Do NOT routinely offer carotid intervention to all patients with TIA.
Indications for carotid intervention depend on the severity of stenosis (reported with the NASCET method):
- Severe stenosis (50-99%) → perform carotid endarterectomy (on the problematic side only) within 7 days
- If unfit for surgery → consider carotid angioplasty and stenting
- Mild / moderate stenosis (<50%) → no intervention
DVLA Guidelines
TIA and Driving
After a stroke / TIA → always stop driving immediately. Further action depends on the license type:
- Class I vehicle (car / motorcycle)
- Stop driving for at least 1 month
- No need to inform the DVLA routinely (unless there is residual neurological / cognitive deficit after 1 month or there was any seizure or brain surgery was performed)
- Class II vehicle (bus / coach / lorry)
- Must inform the DVLA
- Stop driving for at least 1 year (12 months)
References