TIA Flashcards
What is a TIA?
transient neurological dysfunction caused by focal brain, spinal cord, or retinal ischaemia, without evidence of acute infarction <24 hours
transient reduction in blood flow to an area of cerebral tissue that causes neurological symptoms
Causes of TIA?
- Atherothomboembolism: from carotid- listen for bruits
- Cardioembolism: Mural thrombus post MI, AF, valve disease, prosthetic valve
- Hyperviscosity: Sickle cell anaemia, polycythaemia, myeloma
- Vasculitis
Risk factors for TIA
Smoking
Diabetes mellitus
Hypertension
Hypercholesterolaemia
Obesity
Atrial fibrillation
Carotid artery disease
Age
Thrombophilic disorders (e.g. antiphospholipid syndrome)
Sickle cell disease
What are the clinical features of a TIA?
A TIA presents with sudden, focal neurological deficit that reflects the area of the brain devoid of blood flow.
Neurological deficit
- Unilateral weakness or sensory loss
- Dysphasia
- Ataxia, vertigo, or incoordination
- Amaurosis fugax - retinal artery occluded - unileral progressive vision loss ‘like a curtain descending’
- Homonymous hemianopia
- Cranial nerve defects: particularly if associated with contralateral sensory/motor deficits
- Global evens (e.g. dizziness/syncope) are not typical of TIAs
What are cresendo TIA’s? What do they suggest?
Mutiple highly stereotyped TIAs
Suggest intracranial stenosis (commonly superior division of MCA)
Amorosis fugax cause?
principle cause of amaurosis fugax is transient obstruction of the ophthalmic artery, which is a branch of the internal carotid artery. However, other ischaemic causes to consider include giant cell arteritis (i.e. temporal arteritis) and central retinal artery occlusion. An important differential of transient visual loss, particularly in young patients, is migraine.
What do you do if patinet with suspected TIA has ongoing sx?
Urgent referral to stroke unit
What should you ask in a TIA history?
- Onset & duration of symptoms
- Associated symptoms (suggest alternative diagnosis): headache, vomiting, syncope, seizures
- Neurological deficit
- Cardiovascular risk factors: hypertension, diabetes, smoking, high cholesterol, family history
- Co-morbidities: heart disease, atrial fibrillation, carotid disease, previous stroke/TIA
- Anticoagulation history
- Clinical examination: cardiovascular exam including BP, neurological examination, fundoscopy
- NOTE: patients on anticoagulation with new neurological deficits require urgent admission and exclusion of intracerebral bleeding
Differential diagnosis for TIA?
- Toxic/metabolic: hypoglycaemia, drug and alcohol consumption
- Neurological: seizure, migraine, Bell’s palsy
- Space occupying lesion: tumour, haematoma
- Infection: meningitis/encephalitis, systemic infection with ‘decompensation’ of old stroke
- Syncope: extremely uncommon presentation of TIA, many causes
- Hyperventilation
- Retinal bleeds
Referral for TIA
All patients with a suspected TIA should be referred to a specialist TIA clinic and be seen within 24 hours.
At the TIA clinic, patients should have a comprehensive medical assessment including blood tests, electrocardiogram (ECG) and imaging. If the episode occurred > 1 week ago, the assessment should be within 7 days.
ABCD2 score
Investigations for TIA
Investigations for TIA
(oxford clinical handbook)
Which patients require urgent admission with TIA?
- ≥1 suspected TIA (crescendo TIA): typically within the last 7 days
- Suspected cardioembolic source or severe carotid stenosis
- Vulnerable patient: lack of reliable observer at home to monitor for worsening symptoms
- Bleeding disorder or taking an anticoagulant
because of the high risk of stroke, bleeding or deterioration.
What is the management of TIAs?
Treatment of TIA (acute)
Pulse notes
300 mg of aspirin for 2 weeks
This is followed by treatment with 75 mg of clopidogrel as long-term vascular prevention.
Patients with atrial fibrillation or significant carotid artery disease require a different treatment pathway.
- Atrial fibrillation (AF): should be offered and counselled about starting an oral anticoagulant
- Carotid artery disease (CAD): urgent referral for consideration of carotid endarterectomy if significant disease. Based on NASCET or ECST criteria for stenosis.
NASCET: 50-99% stenosis
ECST: 70-99% stenosis
Treatment for TIA (secondary prevention)
- Anti-hypertensives: as per hypertension guidelines (tolerate higher if significant bilateral CAD)
- Lipid modification: offer high-dose statin therapy unless contraindication.
- Diabetic control: treat any new diagnosis of diabetes and optimise control of pre-existing disease
- Obstructive sleep apnoea: referral to specialist sleep medicine/respiratory clinic if suspected
- Pre-menopause: use of combined oral contraceptive pill contraindicated.
**Lifestyle measures **
Basic advice on physical activity, smoking cessation, diet optimisation and alcohol intake should be given to all patients
Drving following a TIA
- Cars and motorcycles: stop driving one month, do not need to inform DVLA
- Larger vehicles (e.g. buses, lorries): stop driving, inform the DVLA
Management algorithms for TIA and stroke
