Ischaemic Stroke Flashcards
(38 cards)
what are the 3 pathologies included in cerebrovascular disease (stroke)
thrombosis, embolism, haemorrhage
what is a stroke
abnormality in the brain caused by a pathological process of the blood vessels
cliincal syndrome: rapid onset of focal disturbance in cerebral function of vascular origin longer than 24 hrs
describe ischaemic vs haemorrhagic strokes
I = thrombosis/embolism
H = bleeding by ruptured artery
what should you ask in a pateint history for stroke diagnosis
time of onset, history of mini strokes (TIA), pattern of symptom progression, specifical focal symptoms, co existing diseases
what happens during physical exam and lab diagnostics for stroke diagnosis
neuro evaluation of mental status, consciousness, cranial nerves, motor + sensory function, cerebellar function, gait, deep tendon reflexes
complete blood count, chemistry panel, coagulation studies, cardiac enzymes
CT scan
What does cerebral infarction lead to
irreversible cell death
which factors influence the size of the infarct
availability of collateral circulation
duration of iscahemia
magnitude of reduction in cerebral blood flow
what is a pale infarct
non-haemorrhagic, usually thrombosis
what is a red infarct
haemorrhagic
caused by petechial haemorrhages
associate with embolic events
what is the penumbra
potentially salvageable tissue
cells vant function but they’re not dead yet
can be rescued by reperfusion
which secondary factors can cause neuronal death
inflammation, excitotoxicity, loss of ion homeostasis, oxidative stress, mitochondrial damage. disruption of blood brain barrier, cerebral oedema
What is reperfusion injury
worsening of injury upon restoration of blood flow
what type of damage can occur to blood vessels during iscaemia
disruptions to bbl’ccausing
extravasation of fluid and proteins and rbcs to the brain parenchyma
what do injured endothelial cells within the capillaries and arteioles cause
inflammation = release of inflam mediators and WBCS causing cellular damage
and generation of free radicals -> destructive enzymes
What is TIA
mini stroke, indicator of underlying thrombotic disease
same underlying pathology as stroke
brief period of inadequate cerebral perfusion. lasts mins-hours
disturbance reverses before infarction occurs
symptoms resolve
cuases of tia
atherosclerotic plaque = break off and obscure vessel + thrombus formation
increased blood viscosity and clot formation
temporary vasospasm
TIA mimcs
migraine
glucose abnormalities
brain tumours
demyelinating diseases
within which vessels is the occlusion occurring?
larger arteries (ICA, MCA, BA)
describe formation of thrombotic stroke
caused by arterial occlusion
artieral wall damage causes blood coag and narrowing vessel
plaques form at branches and curves in circulation
eventually occludes vessel
what is the most common cause of cerebral infarction
cerebral atherosclerosis
what is an embolic stroke and describe the speed of its onset
thrombus fragments that have formed outside the brain, lodging in cerebral vessel
sudden onset and big sections of brain
individuals with what pathologies are likely to have emboli formation
atrial fibrilation, recent myocardial infarction, bacterial endocarditis, hypercoaguable etc
what is large vessel disease
big areas of stroke
ischaemic stroke
thrombosis is common cause, within carotid or vertebral artieries
can also happen from embolisms
what is a lacunar stroke
small vessel disease
usually more than 1 present
located in deep, non-cortical structures like internal capsule, basal ganglia, brain stem
territory of single penetrating artery of a large cerebral artery eg mca
