Part 3 stroke Flashcards
Common causes of ischemic stroke
____________
Myocardial infarction
atrial fibrillation
atherosclerosis
Transient ischemic attack (TIA)
Also known as mini-stroke
Symptoms similar to regular stroke
____________; less than 24 hrs
No _________ brain damage
Often precedes more severe stroke
temporary
no permanent brain damage
__________:traveling blood clot
embolic stroke
________:local blood clot
thrombotic stroke
_________: middle area (watershed area) not getting enough blood
watershed stroke
Brain regions supplied by major cerebral arteries
Ischemic cascade (in ischemic stroke)
ischemia–>lack of _______
1.Switch from oxidate phosphorylation to anaerobic metabolism–>15x less ATP generation per glucose
2.lactic acid production
oxygen
Problem of less energy (ATPs)
___________—>Increase Na–>Water flows in–>
Calcium toxicity—>increase in intracellular Ca2+—>increase in glutamate–>________
mitochondrial dysfunction and apoptosis (cell suicide)
Cytotoxic edema
Excitotoxicty
____________
Blood flow less than 20% of normal
decrease glucose and oxygen
Necrosis (within a few min)
Ischemic core
___________
paene=almost+ulmbra=shadow
almost a shadow or partial shadow
the tissue neighboring the core, not going to die immediately due to collateral arteries–>some glucose and O2, but only for a few hrs, the aim of the therapy then is to rescue the issue in penumbra ASAP
Penumbra
Hemorrhagic stroke
25% of strokes
Aneurysm–>Rupture–>
Bleeding
____________regions of brain most susceptible to ischemia
Watershed
Hemorrhagic stroke
Loss or inadequate blood supply downstream–>primary stroke
Blood cannot be drained–> Increase intracranial pressure
Released blood products–>irritation of neighboring blood vessels–>vasopasms and narrowing–>secondary stroke
Hemorrhagic stroke:
Causes: __________ Ballooning out of the vessels–>weakened vessel walls–> chronic hypertension
Berry aneurysm:Spontaneously ruptures or following physical trauma
Anenurysm
Causes of Hemorrhagic stroke
___________(AVM): artertioles directly connected to the venous side (bypassing capillaries)
Problem of having a high-blood pressure system going directly into veins, a low-pressure system—>high risk of rupture
Congential (developmentally malformed)
Arteriovenous malformation (AVM)
Post-stroke inflammation
1)Brain cell death
2)Release of damage associated molecular pattern (DAMP)–>Trigger inflammatory response
3)Recruitment of inflammatory cells
4) Switch to anti-inflammatory role
5)Liquefactive necrosis begins
Neutrophils release hydrolases–>digestion of dead cells
6)Cavity formation
Common cause of ischemic stroke
Atherosclerosis plus thrombosis or ____________
thromboembolism
Major risk factor of ischemic stroke:
___________
Hypertension
Lack of O2—>Lack of ATP
1)cytotoxic edema due to accumulation of sodium
2)accumulation in calcium causes excessive release of glutamate which causes excitotoxicity
3)cell death pathways
