1. Transient Ischaemic Attacks
in East Lancashire
21 November 2012
Dr Arun Kumar Singh Consultant Physician
East Lancashire Hospital NHS Trust

2. Transient ischaemic attack (TIA)
A clinical syndrome characterized by an acute loss of focal cerebral or monocular function with symptoms lasting less than 24 hours and which is thought to be due to inadequate cerebral or ocular blood supply as a result of low blood flow, arterial thrombosis or embolism associated with diseases of the arteries, heart or blood.
Hankey & Warlow 1994

3. TIA = “brain attack” = “Mini stroke”
Definition as for stroke except lasts < 24 hours (and not fatal)
Vast majority are ischaemic

4. TIA: Background
About transient ischaemic attacks (TIAs) are diagnosed every year in the in the UK with an overall incidence approaching that of ischaemic stroke
Patients with TIA are generally unstable
However, most patients with TIA will have a benign short-term course
Identification of those at highest and lowest risk of stroke would allow appropriate use of costly secondary prevention strategies, including hospital admission

5. Pathology of TIA/stroke
5% - subarachnoid
haemorrhage
15% - intracerebral
haemorrhage
80% - ischaemic
stroke
Atherothromboembolism
50%

6. Pathology of TIA/stroke
5% - subarachnoid
haemorrhage
15% - intracerebral
haemorrhage
80% - ischaemic
stroke
Atherothromboembolism
50%

7. Pathology of TIA/stroke
5% - subarachnoid
haemorrhage
15% - intracerebral
haemorrhage
Lenticulostriate arteries arising from the trunk of the middle cerebral artery
80% - ischaemic
stroke
Intracranial small
vessel disease
25%

8. Pathology of stroke 5% - subarachnoid haemorrhage Lacunar infarction
15% - intracerebral
haemorrhage
80% - ischaemic
stroke
Intracranial small
vessel disease
25%

9. Prognostic Indicators

10. The ABCD2 Score Age > 60 years 1 point
BP (sys >=140 or dias >= point
Clinical features of TIA
Unilateral weakness or… 2 points
Speech impairment without weakness 1 point
Duration
> 60 minutes points
10 – 59 minutes point
Diabetes Mellitus point
Score Range

12. Use of ABCD2 score
Does not replace clinical diagnostic skill or acumen
This has be incorporated into new local TIA guidelines for investigation or fast-track out-patient referral
A score of 4 or more in a patient with a clinical TIA will likely trigger referral for seeing patient within 24 hrs

13. page Stroke coordinator
Use of ABCD2 score
TIA patient
After 72 hours
Single Event
After 72 hours but
>1 Event in 1 week
Within 72 hours
ABCD2 score
Weekly TIA clinic
Immediate
Telephone RBH
page Stroke coordinator
0-3
4-7

14. TIA SERVICE IN ELHT 7 Days service On Weekends only high risk TIA seen
Only 1 Doppler slot

15. REFERRAL TO TIA SERVICE
Ring RBH switchboard and page 387 (Stroke coordinator)
Have Patient present with you
Anyone with ABCD2 score of 4 or more will be given appointment on the same day or next day as you ring
All other referrals will be seen within a 7 days period
Ensure patient understands this is an emergency clinic – may have to wait
Numbers not capped

16. Patients’ Journey TIA or non stroke pathology decided in clinic TIA
Carotid Doppler if appropriate
Anti-platelet
Cholesterol Management
BP management
Cardiac Investigations
Driving advice
Lifestyle advice by Stroke nurse

17. NICE guidelines: Rapid recognition of symptoms and diagnosis
In people with sudden onset of neurological symptoms a validated tool, such as FAST, should be used outside hospital to screen for a diagnosis of stroke or TIA
In people with sudden onset of neurological symptoms, hypoglycaemia should be excluded as the cause of these symptoms

18. Assessment – High Risk
People who have had a suspected TIA who are at high risk of stroke (that is, with an ABCD2 score of 4 or above) should have
aspirin (300 mg daily) started immediately
specialist assessment and investigation within 24 hours of onset of symptoms
measures for secondary prevention introduced as soon as the diagnosis is confirmed, including discussion of individual risk factors
People with crescendo TIA (two or more TIAs in a week) should be treated as being at high risk of stroke, even though they may have an ABCD2 score of 3 or below

19. Assessment - low risk
If risk of stroke low (i.e. an ABCD2 score of 3 or below) should have:
aspirin (300 mg daily) started immediately
specialist assessment and investigation as soon as possible, but definitely within 1 week of onset of symptoms
measures for secondary prevention introduced as soon as the diagnosis is confirmed, including discussion of individual risk factors
People who have had a TIA but who present late (more than 1 week after their last symptom has resolved) should be treated as though they are at lower risk of stroke

21. Suspected TIA – referral for urgent brain imaging
TIA who are at high risk of stroke (vascular territory or pathology is uncertain) should undergo urgent brain imaging (preferably diffusion-weighted MRI [magnetic resonance imaging])
TIA who are at lower risk of stroke (vascular territory or pathology is uncertain) should undergo brain imaging (preferably diffusion-weighted MRI)
Diffusion-weighted MRI is the investigation of choice except where contraindicated in which case CT (computed tomography) scanning should be used

23. MRI SCAN

24. Duration of attack and percentage of patients with a relevant infarct on CT
Koudstaal et al 1992 JNNP;55:95

25. Warfarin-Aspirin Recurrent Stroke Study (WARSS) Trial
Is Warfarin Really a Reasonable Therapeutic Alternative to Aspirin for Preventing Recurrent Noncardioembolic Ischemic Stroke?
Warfarin Is Equally Effective as Aspirin
As warfarin is used secondary to a cause (AF, DVT, Metal valve etc) there is no need to stop warfarin
This is different if patient has a stroke

26. …and the role of Carotid Endarterectomy
Amaurosis Fugax
…and the role of
Carotid Endarterectomy

27. Definition
Unilateral transient loss of vision. This may be partial or complete, related to retinal arterial microembolization or hypoperfusion.
It is mostly painless
Described as fleeting darkness or blindness
Retinal transient ischemic attack (RTIA)
Transient monocular blindness (TMB)
Accounts for 25% of anterior circulation transient ischemic attacks (TIAs).

28. Amaurosis Fugax..
Amaurosis fugax is a symptom of carotid artery diseases
It occurs when a piece of plaque in a carotid artery breaks off and travels to the retinal artery in the eye

29. Etiologies: Transient visual loss
Occlusive retinal artery disease
Atheroembolic, cardioembolic, arteritic, hematological disorders, congenital, orbital tumor
Low retinal artery pressure
Ocular ischemia syndrome, arteriovenous fistula, congestive heart failure, anemia
Optic disc disease and anomalies
Papilloedema, Glaucoma, Drusen
Vasospasm (ophthalmic migraine)
Miscellaneous
Uhthoff’s phenomenon, classic migraine

32. Conclusions
Amaurosis Fugax is caused by ischemia to the retina, often associated with carotid stenosis, and is a risk factor for stroke
Prognosis is better for patients with amaurosis fugax treated both medically and surgically compared to patients with hemispheric TIAs
Amaurosis Fugax should be recognized, with strong consideration for carotid endarterectomy with high grade carotid stenosis, vascular risk factors present, and low complication rate of procedure in your centre

33. Driving advice: Updated: May 2012
Group 1 entitlement ODL – car, motorcycle
TIA No need to notify DVLA, must not drive for 1 month

34. Driving Advice- Group 2 entitlement vocational – lorries, buses
Licence refused or revoked for 1 year.
Can be considered for licensing after 1 year
No debarring residual impairment likely to affect safe driving
No other significant risk factors. 
(This is subject to satisfactory medical reports including exercise ECG testing)
Imaging evidence of less than 50% carotid artery stenosis
no previous history of cardiovascular disease
(Group 2 licensing may be allowed without the need for functional cardiac assessment
However, if there are recurrent TIAs or strokes functional cardiac testing shall still be required

35. Key points TIA is a medical emergency
There is no diagnostic test for TIA
Diagnosis can be very difficult or relatively easy
Diagnosis rests almost entirely on the history, balance of risk factors and selected targeted investigations
Attacks occur suddenly, are maximal in severity within seconds-minute, affect all areas simultaneously
Loss of consciousness is EXCEEDINGLY uncommon
Isolated Dizziness or diplopia is EXCEEDINGLY uncommon
Peripheral pain is very UNUSUAL
Headache is not unusual (15-20%)

36. ALWAYS ADVISE ON DRIVING
Key points…
Prescribe ASPIRIN 300mg stat then 75mg Clopidogrel regularly
Fax referral to TIA clinic
Patients with > 1 TIA in 1/52 or high ABCD2 score >5 should be investigated in hospital
ALWAYS ADVISE ON DRIVING