1. Transient Ischaemic Attacks
Dr Gillian Mead

2. Overview Definition Making the diagnosis (and common differentials)
Risk Stratification
Investigation
Management

3. What is a TIA? Clinical definition (1st appeared in 1950’s)
Abrupt onset
Focal neurological symptoms/deficit
includes monocular blindness
Last less than 24 hours
Presumed to be “vascular” in origin after “appropriate” investigation

4. FOCAL neurological symptoms
weakness of face / arm /leg on one side
sensory disturbance of face / limbs on one side * **
amaurosis fugax (transient monocular blindness)
language disorder (aphasia)
homonymous visual field loss
sudden bilateral blindness
diplopia*
dysarthria*
* caution if this is the only symptom
** caution if the sensory symptoms only last minutes

5. NON-FOCAL neurological symptoms (= NOT TIA)
loss of consciousness
faintness
generalised weakness
Vertigo only
drop attacks
confusional episodes

6. The importance of an accurate diagnosis
Explanation of the symptoms for the patient
Guides the search for underlying pathology
sources of embolism
disease of large or small blood vessels
haematological problem
haemodynamic problems
Prognosis
Appropriate management
Driving advice
1/12 for single TIAs, 3/12 for frequent TIAs
HGV: different rules apply

7. The diagnosis is not always easy
Many patients referred with TIAs to hospital have not had them
Only moderate inter-rater reliability even between experts
Pattern recognition is important
Good history (may need to ask a witness)
Ask the right questions
Lots of clinical experience

8. Diagnoses made in patients referred to a Neurovascular clinic
Cardiac syncope
Cough/micturition syncope
Postural hypotension
Hyperventilation
Sleep apnoea
Hypoglycaemia
Neurological problems
Migraine (+/- headache)
Epilepsy
Transient global amnesia
Glioma
Meningioma
Cerebral metastases
Subdural haematoma
Lymphocytic meningitis
Peripheral neuropathy
Guillain–Barré syndrome
Cervical myelopathy
Brachial neuritis
Herpes Zoster neuropathy
Bell’s palsy
Syringobulbia
Myasthenia gravis
Multiple sclerosis
Motor neurone disease
Psychiatric problems
Somatisation disorder
Ophthalmic problems
Retinal vein occlusion
Glaucoma

9. 85 year old man
Referred to CAA with recurrent episodes of right arm weakness
Diagnosis of TIA
Referred to stroke team
Detailed history: writing had ‘not been right’ for a few weeks
CT brain showed left hemisphere metastases

10. Mr B, a 41 year old male
3 weeks, episodes of ‘tingling’ and paraesthesia over part of the left arm and upper part of left leg
Attacks became more severe and more frequent, & involved the whole of the left side of the body.
Symptoms spread: from the hand to the head over one minute.

11. Mr B, a 41 year old male No cerebrovascular or cardiovascular disease
Ex-smoker.
BP 140/75
Examination normal
Diagnosis: transient ischaemic attacks

12. CT scan CT showed a glioma in right sensory cortex
Attacks were NOT TIA; the correct diagnosis was sensory epileptic seizures

13. 50 year old lady
At work, sudden onset of left arm tingling and very mild weakness
Referred to stroke team as ? Stroke
o/e left arm drift, subjective reduced sensation.
On direct questioning, reported dull headache starting a few hours afterwards
No vascular risk factors
Had migraine in her 20s, none recently
CT brain normal
Referred to neurology: MRI showed small deep infarct in right internal capsule, based on history, diagnosis was migraine, infarct was a result of vasospasm

14. Bilateral subdural haematoma
This scan shows low density areas (arrows) over the surface of the cerebral hemispheres. These are due to blood in the subdural space. More often the bleeding is on one side and can mimic a stroke although the symptoms usually come on more slowly. The blood can be removed surgically. Often such bleeding occurs after head injury and in patients taking anticoagulants

15. A brain tumour
This shows a rounded lesion (white ) with surrounding swelling (black). The tumour itself is showing up white because the radiologist has injected a dye (contrast media) which is taken up by the tumour. This is a brain tumour which can sometimes produce symptoms similar to those of a stroke. Typically however the symptoms of a brain tumour would worsen over days or weeks rather than coming on over minutes or hours.

16. Diagnosing TIAS Invite any witnesses to the consultation
See the patient as early as possible after the event
Take a full narrative history of event
Collect circumstantial evidence from history
Investigate to collect further circumstantial evidence

17. Important points from history
Demographic details
Onset and time course
Number of events and duration
Precipitating factors (position,drugs etc)
Nature of symptoms
Vascular risk factors or relevant co-morbidity

18. Risk Stratification

19. High early risk of stroke after TIA14
OXVASC
OCSP 12 10 8
Risk of stroke (%) 6
10% risk of stroke by 7 days 4 2 7 14 21 28
Days
Lancet 2005; 366: 29-36

20. ABCD2 Score Factor Category Score Age Age≥60 Age<60 1
Blood pressure at assessment
SBP>140 or DBP≥90
Other
Clinical Features
Unilateral weakness
Speech disturbance (no weakness) 2
Duration
≥60 minutes
10-59 minutes
<10 minutes
Diabetes
Yes No
And here is the score
Age over 60 and SBP>140 or DBP>=90 score one- otherwise zero
Any unilateral weakness score scores 2 while speech disturbance without weakness scores 1
Symptom duration was categorised around 10 and 60 minutes, scoring 2, one or zero.

21. Stroke risk (%) Score 1-3 LOW 2-day risk* 1% Score 4-5 MODERATE
HIGH
risk 8%
Stroke risk (%)
Johnstone Lancet

22. Refining ones prognosis Factors associated with increased risk of stroke
Increasing age
Brain TIAs
Number of recent TIAs
Peripheral vascular disease
Carotid stenosis
percentage
ulceration/irregularity

23. Routine Investigations
Full blood count
Erythrocyte sedimentation rate
Urea & Electrolytes
Blood glucose
Cholesterol
ECG

24. Investigations on selected patients
Carotid Duplex (for pts with carotid TIAs)
CT Brain scan or MRI (for multiple cerebral attacks)
Echocardiogram
24 hour ECG
Lupus anticoagulant
Thrombophilia screen

25. Treatment strategy Treat any specific underlying cause
Modify vascular risk factors
Smoking
Diabetes
Specific therapies
Antiplatelets drugs
Antihypertensives
statins
Anticoagulants
Carotid endarterectomy

26. Days from medical attention
EXPRESS: Clinic-referred population 2 4 6 8 10 30 60 90
Days from medical attention
Risk of stroke (%)
NV clinic
P<0.0001
Same day clinic
HIGHER-RISK CASES – FASTER – 5%.

27. TIA hotline introduced

28. Smoking cessation Encourage spouses to give up
Confiscate cigarettes in clinic
Change their habits
Encourage use of nicotine replacement therapy
Smoking cessation service
Support groups
Hypnosis/acupuncture

29. Ranking antiplatelet treatment What the trials tell us
None
Less effective
More effective

30. Ranking antiplatelet treatment What the trials tell us
Trialists
Collaboration
None
Aspirin
Less effective
More effective

31. Ranking antiplatelet treatment What the trials tell us
CAPRIE
Trial al
Clopidogrel
None
Aspirin
Less effective
More effective

32. Ranking antiplatelet treatment What the trials tell us
Aspirin +
Clopidogrel al
MATCH
& CHARISMA
Trials
Clopidogrel
None
Aspirin
Less effective
More effective

33. Ranking antiplatelet treatment What the trials tell us
Aspirin +
Dipyridamole
ESPS 2 & ESPRIT
Trials al
None
Aspirin
Less effective
More effective

34. Ranking antiplatelet treatment What the trials tell us
Aspirin +
Dipyridamole
PROFESS
Trial
Clopidogrel
Less effective
More effective

35. Ranking antiplatelet treatment What the trials tell us
Aspirin +
Dipyridamole
Aspirin +
Dipyridamole
Aspirin +
Clopidogrel al
Clopidogrel
None
Aspirin
Less effective
More effective

36. Antiplatelet Drugs
Aspirin - treat 100 patients for one year and prevent one stroke
Aspirin & Persantin MR marginally better than aspirin alone but more side effects and cost
Clopidogrel (PLAVIX) marginally better than aspirin used to much more expensive (x1000)
Clopidogrel now much cheaper, so we are tending to use this instead of the asp/dipyridamole combination

37. Blood pressure reduction
Uncertain how soon to start
Likely to work but little direct evidence in TIA/ stroke patients
Lifestyle changes
Benefits of blood pressure lowering per se (we generally aim for target of 130/70)
Uncertain optimal regime (depends a bit on what they are already taking)
Care needed in haemodynamic TIAs

38. Cholesterol Reduction
Statins if cholesterol >3.5mmol/l

39. Anticoagulants (Warfarin)
Used in patients with
Atrial fibrillation
Prosthetic heart valves
Recent myocardial infarction
80 events avoided per 1000 patient treated

40. Anticoagulants If Atrial Fibrillation Prosthetic heart valve
INR 2-3 if no definite contraindication
Cardioversion not of any value
Prosthetic heart valve
consider combination with aspirin
Sinus rhythm
consider Heparin in crescendo TIAs

41. Falls and warfarin
Falls: patient with an average risk of stroke from AF (5% per year), it would require the patient to fall roughly 300 times per year for the risks of anticoagulant therapy to outweigh its benefits, in terms of intracranial bleeding (ManSonHing et al)
Yet most physicians perceive falls to be a barrier to anticoagulation

42. Secondary Prevention TIA Ischaemic Risk of recurrence  Sinus rhythm
Severe
carotid
stenosis
Ischaemic
Carotid
surgery
Sinus
rhythm
Atrial
fibrillation
Antiplatelets
Asp + Dip or
Clopidogrel
Cholesterol 
Life style
Blood pressure 
Anticoagulation
Risk of
recurrence 

43. Imaging the blood vessels
Carotid and Vertebral artery Ultrasound
can show atheroma and occlusions of vessels in neck
Transcranial Doppler (TCD)
can show flow (or lack of flow) in large intracerebral vessels
Magnetic resonance angiography
can show extra and intra cranial blood vessels
Catheter angiography

44. Carotid Duplex
Carotid duplex is a simple, risk free outpatient procedure.

45. Stenosis of the origin of the Internal Carotid Artery
There is a severe narrowing of the origin of the internal carotid artery. This is likely to be a source of clots (emboli) which can cause TIAs and strokes. In a patient with such a severe narrowing (>80%) who has had recent TIAs or a minor stroke affecting that side of the brain we would recommend an operation to remover the narrowing. This is called a carotid endarterectomy. Randomised trials have shown that it reduces the risk of stroke

47. Effect of surgery for 50-69% stenosis:
time since last event <2 weeks
Ipsilateral Carotid Territory Ischaemic Stroke
Plus Any Surgical Stroke or Surgical Death
Any Stroke or Surgical Death 1 2 3 4 5 6 7 8 9 10
Patients
Surgery
158
138
129
117
106 90 72 53 36 18
135
124
112 99 84 66 48 34 16
No surgery
150
130
108 94 70 55 45 33 26 15 .
Years from randomisation
0.5
0.6
0.7
0.8
0.9
1.0
Proportion free of event
Log-rank = 10.4
P = 0.001
Log-rank = 8.9
P = 0.003
Stroke 2004; 35:

48. Reduction in the 5-year risk of stroke or death highest if carotid surgery < 2 weeks
70-99% stenosis, highest benefit if surgery < 2 weeks
50-59% stenosis, NO benefit if surgery
> 2 weeks after onset
Absolute reduction in risk
Rothwell, ECST & NASCET investigators, Lancet 2004; 363: 915–24

49. Carotid Endarterectomy
Can be done under local anaesthetic (GALA)
3-5% risk of stroke or death
Operate on to prevent one stroke in next 3 years

50. What is you local surgeons complication rate?
Does he continuously audit his results?
How does he select cases?
Any independent assessment of outcome?
Perform 50 carotid endarterectomies with 2 deaths/strokes
4% (95% CI: %)

51. Summary Careful history critical in making diagnosis
Rapid initiation of secondary prevention
Antiplatelets, anticoagulants, carotid endarterectomy, statins and antihypertensives are the cornerstone to our treatment