What is a crescendo TIA?
Refers to 2 or more episodes of TIA within a week and usually requires urgent specialist evaluation.
What are differentials for TIA?
- Syncope
- Atypical seizures
- Migraine
- Temporal arteritis
- Retinal haemorrhage or detachment
- Hypoglycaemia
- Labyrinthine disorders e.g. BPPV
What is the initial management of TIA?
- Offer aspirin (300mg daily)
- Refer people immediately for specialist assessment and investigation, to be seen within 24 hours of onset of symptoms
- Do not use scoring systems such as ABCD2 to assess risk of subsequent stroke
- Offer 2dary prevention, in addition to aspirin as soon as possible after TIA diagnosis is confirmed (warfarin or DOAC for AF)
What investigations should be done in a specialist clinic?
- BP
- Bloods - FBC, U+E, LFT, lipids
- Height, weight, BMI
- Blood glucose
- ECG
- Carotid artery ultrasound doppler (should be performed asap for patient’s suitable for carotid endarterectomy)
What are the requirements for carotid endarterectomy?
Ensure that people with stable neurological symptoms from acute non-disabling stroke or TIA who have symptomatic carotid stenosis of 50 to 99% according to NASCET criteria (or >70% from ECST):
- are assessed and referred urgently for carotid endarterectomy to a service following current national standards
- receive best medical treatment (control of BP, anti-platelet agents, cholesterol lowering through diet and drugs, lifestyle advice)
What is a carotid endarterectomy?
Removes plaque from the carotid arteries by making an incision along the neck until GA or LA.
When is carotid endarterectomy not indicated?
Ensure that people with stable neurological symptoms from acute non-disabling stroke of TIA, who have symptomatic carotid stenosis of less than 50% from NASCET criteria, or less than 70% according to ECST criteria:
- do not have surgery
- receive best medical treatment (control of BP, anti-platelet agents, cholesterol lowering through diet and drugs, lifestyle advice)
What are the symptoms of a left anterior cerebral artery occlusion?
- Affects left frontal and parasagittal areas
- Causes speech disturbance, behavioural changes and weakness (more likely in contralateral legs than arms)
What are the symptoms of a right anterior cerebral artery occlusion?
- Affects right frontal and parasagittal areas
- Causes behavioural changes and weakness (more likely in contralateral legs than arms)
What are the symptoms of a left middle cerebral artery occlusion?
- Affects left fronto-parietal cortex and subcortical structures
- Causes dysphasia, right visual field defect, right motor or sensory deficits
- Weakness most likely in face, then arm then leg
- MCAs most common site as they are continuation of carotids
What are the symptoms of a right middle cerebral artery occlusion?
- Affects right left fronto-parietal cortex and subcortical structures
- Causes neglect (e.g. neglect to recognise body parts), left motor and sensory deficits
- MCAs most common site as they are continuation of carotids
What are the symptoms of a left posterior cerebral artery occlusion?
- Affects upper midbrain, occipital cortex, thalamus, medical temporal lobes
- Causes visual field deficits, motor or sensory loss
What are the symptoms a right posterior cerebral artery occlusion?
- Affects upper midbrain, occipital cortex, thalamus, medical temporal lobes
- Causes visual field deficits, motor or sensory loss
Describe the function of the basilar artery
- Numerous branches: anterior inferior cerebellar, pontine, superior cerebellar
- Divides at rostral end of midbrain into posterior cerebral arteries (brainstem)
- Occlusion: coma, followed by death due to respiratory failure
What is the development of ischaemic damage?
- Core dead tissue
- Cells in immediate area, die within mins to hrs
- Beyond rescue - Penumbra - vulnerable tissue
- Surrounding region, blood supply compromised but not cut off so cells under threat but not dead
- Potential for rescue
- Must start treatment early
What are the vascular risk factors of a TIA?
- HTN
- Ischaemic heart disease
- Smoking
- Diabetes
- PVD
What are the thrombotic risk factors of a TIA?
- AF
- Polycythaemia
- Combined oral contraceptive pill
- Carotid stenosis
- Clotting disorders
What is the management for a patient if they have had >1 TIA or suspected cardioembolic source or severe carotid stenosis?
Discuss the need for admission or observation urgently with stroke specialist
What are other recognised patterns of stroke?
- Lateral medullary syndrome (posterior inferior cerebellar artery) - aka Wallenberg’s syndrome
- Ipsilateral: ataxia, nystagmus, dysphagia, facial numbness, cranial nerve palsy e.g. Horner’s
- Contralateral: limb sensory loss - Weber’s syndrome
- Ipsilateral III palsy
- Contralateral weakness
