Stroke Flashcards
What is Stroke
Stoppage of blood supply to part of the brain usually due to a clot or bursting of a blood vessel
What are the 2 types of stroke?
Haemorrhagic (Around 15%)
Ischaemic (Around 85%)
What possibles causes for haemorrhagic stroke?
Primary Intracerebal Haemorrhage
Secondary Haemorrhage
(i.e. a burst blood vessel in brain either as a primary pathology or due to something else)
What are the possible causes for ischaemic stroke?
Large Artery Atheroma (the vast bulk of cases)
Emboli:
- Usually Cardioembolic e.g. Afib, IE, MI
Drug Abuse:
- Raises BP causing vessel rupture
Haemotological Disorder:
- E.g. Sickle Cell
Carotid Dissection (Idiopathic or as a result of trauma)
risk factors for stroke?
Male Old Age Hypertension FH Atrial Fibrillation Race (far eastern e.g. chinese are more susceptible in a western enviroment)
What are the possible symptoms of stroke?
Motor loss - Clumsy/weak limbs
Sensory - Loss of feeling
Speech:
- Dysarthia (slurring due to motor loss)
- Dysphasia (Inability to find words or comprehend language)
Vision:
- Loss of one eye vision (Amaurosis Fugax)
- hemianopsia
Nystagmus - Involuntary eye movement
Whats the difference between dysarthia or dysphasia?
Dysarthia is slurring of speech due to motor loss
Dysphasia is loss of ability to find words due to brain problem
What are the types of vision loss in stroke?
Homonymous Hemianopia = loss of the same side of both fields of view
Heteronymous Hemianopia = Loss of opposite halves of each field of view
What is the accepted response to an acute stroke?
If time get emergency CT
Thrombolysis with IV alteplase (tissue plasminogen activator, tPA) ASAP but not if >4.5 hours have elapsed.
Can add Surgical Clot retrieval to increase chances. (thrombectomy)
What can thrombolysis with alteplase cause?
Bleeding in the damaged brain tissue and elsewhere in the body
How else can we investigate a stroke?
Bloods - FBC and Lipid profile
ECG
MRI (shows ischaemic stroke better)
Carotid Doppler US - Shows atheroma and Dissection
Echo - For source of clots in heart (cardioembolic stroke)
What do we use as secondary prevention of stroke?
[Clopidogrel] OR [Aspirin + Dipyridamole] Statins Anti-Hypertensives Diabetic Control Carotid Endarterectomy
In what patients would we consider a carotid endarterectomy?
Definetely for Symptomatics >70% stenosis
Consider for 50-69% symptomatics and >70% asymptomatics
What are the 4 subtypes of stroke?
TACI - Total Anterior Circulation Infarct - Total infarction of anterior supply to one side of brain
PACI - Partial Anterior Circulation Infarct - Partial Infarction of Anterior Supply to one side of brain
LACI - Lacunar Infarct (small vessels) - Most Common Type
POCI - Posterior Circulation Infarct- Infarction of posterior supply to one side of brain
They are refferred to as **S instead of **I, meaning stroke syndrome instead of infarct prior to imaging as we cant yet be sure it is a stroke and not some other condition causing a stroke like syndrome.
Why wouldn’t we do a carotid endarterectomy in a TIA patient with 100% occlusion?
They still have enough flow from the other 3 vessels to prevent stroke and have no risk of embolization.
Treatment should just be catered to prevent future disease in other vessels.
