Transcript Stroke and TIA in Emergency Room

Transient Ischaemic Attacks
in East Lancashire
21 November 2012
Dr Arun Kumar Singh
Consultant Physician
East Lancashire Hospital NHS Trust
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
TIA = “brain attack” =

“Mini stroke”

Definition as for stroke except lasts < 24
hours (and not fatal)

Vast majority are ischaemic
TIA: Background

About 70 000 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
Pathology of TIA/stroke
5% - subarachnoid
haemorrhage
15% - intracerebral
haemorrhage
80% - ischaemic
stroke
Atherothromboembolism
50%
Pathology of TIA/stroke
5% - subarachnoid
haemorrhage
15% - intracerebral
haemorrhage
80% - ischaemic
stroke
Atherothromboembolism
50%
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%
Pathology of stroke
5% - subarachnoid
haemorrhage
Lacunar infarction
15% - intracerebral
haemorrhage
80% - ischaemic
stroke
Intracranial small
vessel disease
25%
Prognostic Indicators
The ABCD2 Score




Age > 60 years
BP (sys >=140 or dias >=90
Clinical features of TIA
1 point
1 point
 Unilateral weakness or…
 Speech impairment without weakness
2 points
1 point
Duration
 > 60 minutes
 10 – 59 minutes
2 points
1 point

Diabetes Mellitus
1 point

Score Range
0-7
Use of ABCD2 score



Does not replace clinical diagnostic skill
or acumen
This has be incorporated into new local
TIA guidelines for investigation or fasttrack 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
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
0-3
Weekly TIA clinic
4-7
Immediate
Telephone RBH
page Stroke coordinator
TIA SERVICE IN ELHT
7 Days service
 On Weekends only high risk TIA seen

 Only 1 Doppler slot
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
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
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
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
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
Suspected TIA – referral for
urgent brain imaging
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TIA who are at high risk of stroke (vascular
territory or pathology is uncertain) should undergo
urgent brain imaging (preferably diffusionweighted 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
MRI SCAN
Persisting
1-6 weeks
1-7 days
5-24 hours
1-4 hours
31-60min
50
45
40
35
30
% of patients with
25
infarct on CT scan
20
15
10
5
0
1-30min
Duration of attack and percentage of
patients with a relevant infarct on CT
Duration of symptoms
Koudstaal et al 1992 JNNP;55:95
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

…and the role of
Carotid Endarterectomy
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).
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
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
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
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Driving advice: Updated: May 2012

Group 1 entitlement ODL – car, motorcycle

TIA
No need to notify DVLA, must not drive for 1
month
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
Key points
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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%)
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