Stroke Pathophysiology Flashcards
Definition of stroke
Work in progress
- trying to include all the clinical scenarios
What are the 2 types of classifications of stroke? Which one is more common
Subtypes?
Ischemic stroke (85%)
- including transient ischemic attack (TIA)
Hemorrhagic stroke (15%)
- intracerebreal hemorrhage
- subarachnoid hemorrhage
- subdural and epidural hematomas
Define ischemic stroke
Episode of neurological dysfunction caused by focal cerebral, spinal, or retinal infarction
- Evidence of focal ischemic injury
- Symptoms persisting 24hrs+
Define TIA
Same as ischemic stroke WITHOUT acute infarction
Symptoms lasting LESS than 24hrs
- “mini stroke”
- indicator or acute ischemia that can happen in near future
T/F is having symptoms alone good for diagnosis
True
What if a patients presents with no symptoms? What is it called
Silent CNS infaraction
Define thrombotic and embolic ischemic stroke
Thrombotic
- infarction located near the clot in the brain
Embolic
- Clot migrated from another source
- ex. Afib and valvular diseases
Define ischemic core or focal region
Tissue that has already sustained irreversible damage
- cannot be salvages
Define penumbra
Tissue at risk
- hypo-perfused tissue with disrupted function
May be salvaged by acute reperfusion therapy
- but delay can lead to permanent is irreversible
Which vessels off the aorta supply blood to brain? (2)
R common carotid artery
L common carotid artery
Which arteries in the head & neck supply blood to brain (2)
Vertebral artery
Internal carotid artery
Why is circle of willis important?
To be able to use alternate routes if a blockage happens
What are the 5 sources of ischemic stroke? %?
25% large artery
25% small artery (lacunes)
20% cardiogenic embolism (afib)
25% cryptogenic (unknown source)
5% Unusual dissections, arteritis
How can large artery atherosclerosis happen?
Commonly due to build of plaque
can be caused due to in-situ thrombosis or artery-artery embolization
Which large arteries are affected in stroke?
Internal carotid artery
Vertebral artery
How can small artery stroke happen (lacunar stroke)
Symptoms?
Endothelial dysfunction leading to occlusion in the small penetrating
- necrotic tissue from the infarct is removed by macrophages, resulting in a formation of a small cavity or lacune
Can be symptomatic or asymptomatic
How does cardiac embolism happen in afib?
Stats?
What are other reasons?
Stall blood in Left atrial appendage
Clot moves from L Atrium to L ventricle
Afib patients have 5 times greater risk
1 in 5 of all strokes can be due to Afib (20%)
Valvular heart disease
Patent Foramen Ovale
Usually attaches to a bifurcation point or narrowed vessel
Define intracerebral hemorrhage?
Where?
Cause?
Very fast neurological signs
within brain parenchyma or ventricular systems
Not caused by trauma
- Main cause is hypertension
Define subarachnoid hemorrhage
Where
Cause
Where
- bleeding into subarachnoid space
- not related to trauma
Cause
- not related due to trauma
- aneurysmal rupture
Define epidural and subdural hemotomas
Where
Cause
Where
- bleeding between the skull and dura
- outside of parenchyma
OR
- between the dura and the arachnoid mater
Cause
- result of trauma
Epidural vs subdural hemotomas
Associated with Head fracture?
Which is worse?
Easier to diagnose?
Associated with Head fracture?
Epidural
Which is worse?
Subdural
Easier to diagnose?
Epidural
How many % of patients die who have a stroke
Ischemic vs hemorrhagic?
15%
15% vs 30%
What % recover completely from stroke?
10%
Which gender is more likely to get a stroke? at what age is the spike?
Men
65+
