Stroke Flashcards
What is a TIA?
An ischaemic usually embolic neurological event with symptoms lasting less than 24h. This is what makes it transient.
Without intervention more than 1 in 12 patients will go on to have a stroke within a week.
Signs of TIA.
The signs will be specific to the artierial territory and what part of the brain that artery supplies.
E.g. amaurosis fugax can occur when the retinal artery is occluded. This causes unilateral progressive vision loss like curtain descending.
Global events like syncope and dizziness are rare but can happen.
Attack may occur in singularity but can also be many.
What do multiple highly stereotyped attacks aka crescendo TIAs suggest?
Critical intracranial stenosis commonly in the superior division of the MCA.
Causes of TIA.
Atherothromboembolism of the carotid is the main cause - listen for bruits.
Cardioembolism such as a mural thrombi post-MI or in AF, valve disease or in prosthetic valve.
Hyperviscosity - polycythaemia, sickle cell anaemia and myeloma.
Vasculitis is a non-embolic cause.
Differentials of TIA.
Hypoglycaemia
Migraine aura
Focal epilepsy
Hyperventilation
Retinal bleeds
Rare mimics such as;
Malignant hypertension
MS
Intracranial tumours
Peripheral neuropathy
Phaeochromocytoma
Somatisation
Investigation in TIA.
Bloods - FBC, U&Es, ESR, Glucose, Lipids,
CXR
ECG
Carotid doppler
CT and MRI
Echocardiogram
Treatment of TIA.
Similar to stroke patient should be given Aspirin 300mg OD for 2 weeks and then be switched onto clopidogrel 75mg OD.
If this is CId then give aspirin 75mg OD combined with slow-release dipyridamole.
Control cardiovascular risk factors
Anticoagulation indications if need be
Carotid endarterectomy.
Explain control of cardiovascular risk factors in TIA.
Optimise BP ( < 140/85 mmHg)
Hyperlipidaemia
DM
Help stop smoking
When should a carotid endarterectomy be done?
Perform within 2 weeks of first presentation if 70-99% stenosis and operative risk is acceptable.
When should antiocoagulation be done in TIA?
If there is a cardiac source of emboli.
How should people with crescendo TIA (two or more TIAs in a week) be treated?
As being at high risk of stroke.
What is the risk assessment tool designed to improve the prediction of short-term risk of a stroke after a TIA?
ABCD2 score.
Explain the ABCD2 score.
Age > 60 (1)
BP >140/90 (1)
Clinical features
Unilateral weakness (2)
Speech disturbance without weakness (1)
Duration of symptoms
> 1h (2)
10-59 min (1)
Diabetes (1)
What do different scores in ABCD2 tell you?
4 or more indicates that the patient is at high risk of an early stroke and must be assessed by a specialist within 24h.
A score of 6 or more strongly predicts a stroke (8.1% within 2 weeks and 35.5% in the next week)
Driving and TIA.
Prohibited from driving for at least 1 month.
What is a stroke?
A sudden onset of a focal neurological deficit lasting more than 24 hours or with imaging evidence of brain damge due to either infarction or haemorrhage.
Causes of stroke.
Small vessel occlusion/cerebral microangiopathy or thrombosis in situ.
Cardiac emboli
Atherothromboembolism form e.g. carotids.
CNS bleeds
Carotid artery dissection
Vasculitis
SAH
Venous sinus thrombosis
Antiphospholipid syndrome
Thrombophilia
Fabry disease
CADASIL
Differentials of strokes.
Head injury
Hypo/hyperglycaemia
Subdural haemorrhage
Intracranial tumours
Hemiplegic migraine
Post-ictal
CNS lymphoma
Wernicke’s encephalopathy
Hepatic encephalopathy
Encephalitis
Toxoplasmosis
Cerebral abscesses
Mycotic aneurysm
Drug overdose
What can be used to help medical staff distinguish between a stroke and a stroke mimic?
ROSIER scale.
Explain ROSIER scale.
Stands for Rule Out Stroke In the Emergency Room
Risk factors of stroke.
HTN
Smoking
DM
Heart disease
Peripheral vascular disease
Increased PCV
Carotid bruit
COCP
Dyslipidaemia
Alcohol use
Increased clotting
Low antithrombin III
etc…