B7-063 Stroke Cases Flashcards
sudden onset of focal brain deficits from blockage or rupture of cerebral blood vessel
stroke
3 common causes of ischemic stroke
large vessel artherosclerosis
cardiogenic emboli
small vessel disease
is hemorrhagic or ischemic stroke more common?
ischemic
cardiogenic emboli usually consists of […] clot
red
irregularly irregular rhythm on EKG
a-fib
diagnostic test for cardiogenic emboli [3]
continous EKG (a-fib)
TTE
TEE
primary source of cardiogenic embolism
non-valvular a-fib
mainstay of therapy for patients with a-fib
anticoagulation to prevent ischemic stroke
direct oral anticoagulants
apixaban
edoxaban
dabigatran
rivaroxaban
in patients with a-fib and strong contraindication for anti-coagulation, what is an alternate therapy?
watchman device inserted to left atrial appendage
most common mechanism of ischemia from large vessel artherosclerosis
artery to artery emboli
(like at carotid bifurcation)
diagnostic tests for artherosclerosis based stroke [2]
angiography (usually CT)
carotid US
risk factors for artherosclerosis based stroke
hypertension
smoking
hyperlipidemia
diabete mellitus
prevention of artherosclerosis based stroke [3]
treat risk factors
antiplatelets (no anti-coagulation)
carotid endarterectomy/stenting
anti-platelet medications [3]
aspirin
clopidogrel
ticagrelor
is diabetes a modifiable risk factor for stroke?
no, blood sugar control has not been shown to decrease risk
when is carotid endarterectomy indicated?
symptomatic (stroke) patients with greater than 70% occulsion
(risk of perioperative MI is too high in asymptomatic, or symptomatic patient with only moderate stenosis)
common mechanisms of penetrating artery occlusion leading to small vessel strokes [2]
lipohyalinosis
microatheroma
risk factors for lacunar strokes
hypertension
maybe DM
poorly studies
[…] are assumed to be effective for prevention of lacunar strokes
anti-platelets
most common cause of ischemic stroke
cryptogenic
unusual causes of ischemic stroke [2]
aterial dissection
drug abuse (cocaine, meth)
thrombolytics [2]
TPA (IV alteplase)
tenecteplase
thombolytics are effective up to […] are onset of ischemic stroke
4.5 hours
catheter thrombectomy is effective up to […] after onset of ischemic stroke
24
catheter thrombectomy is only effective for […] occlusion
proximal large vessel
are thrombolytics or catheter thrombectomy more effective?
catheter thombectomy (if the patient is a candidate)
NNT for TPA=8
NNT for catheter thrombectomy=2
causes of intracerebral intracranial hemorrhage [3]
hypertension
amyloid angiopathy
coagulopathy
common cause of subarachnoid intracranial hemorrhage
ruptured berry aneurysm
thunderclap headache
subarachnoid intracranial hemorrhage
patients with AD can have amyloid angiopathy, causing
lobar intracerebral intracranial hemorrhage
amyloid angiopathy causes intracerebral intracranial hemorrhage where in the brain?
lobar (cortical)
hypertension causes intracerebral intracranial hemorrhage where in the brain?
deep (subcortical)
(thalamus, cerebellum, pons, basal ganglia)
two types of vascular dementia
- history of clinical strokes correlated with onset of cognitive deficits
- no history of clinical strokes, but diffuse subcortical disease on imaging (binswanger disease)
no history of clinical strokes, but diffuse subcortical disease on imaging
binswanger disease (subtype of Vascular dementia)
most ischemic strokes are caused by
emboli
red clot
cardiogenic emboli
most common cause of cardiogenic emboli
non-valvular a fib
most effective way to prevent strokes in patients with atrial fibrillation
anticoagulation
biggest modifiable risk factor for strokes
hypertension
occlusion of the lenticulostriate artery supplying the posterior limb of the internal capsule would cause
contralateral hemiplegia
non-cortical infarcts characterized by the absence of cortical signs
lacunar stroke
pure motor stroke indicates […] artery supplying the […] is affected
lenticulostriate
posterior limb of internal capsule
pure sensory stroke indicates what structure is affected?
thalamus
contralateral hemiparesis and sensory impairment […] artery supplying the […] is affected
lenticulostriate
posterior limb of internal capsule
(can also present with purely motor symptoms)
Infarction of the […] is the most common type of lacunar stroke and may manifest clinically with pure motor stroke, pure sensory stroke (rare), sensorimotor stroke, dysarthria-clumsy hand syndrome, and/or ataxic hemiparesis.
posterior limb of the internal capsule
a berry aneurysm is also called a […] aneurysm
saccular
typically occur at bifurcations in the circle of Willis
berry aneurysm
most common location of berry aneurysm
junction of anterior communicating artery and ACA
what two congentital diseases are associated with berry aneurysm?
Ehlers-Danlos
autosomal dominant polycyctic kidney disease
berry aneurysm causes […] hemorrhage
subarachnoid
compression of the […] due to berry aneurysm causes bitemporal hemianopia, visual acuity deficits, and ischemia in the ACA distribution
anterior communicating artery
rupture of the […] due to berry aneurysm causes ischemia in the MCA distribution
MCA
compression of the […] due to berry aneurysm causes ipspilateral CN III palsy (mydriasis, ptosis, down and out eye)
posterior communicating artery
what symptom can differentiate proximal vs distal MCA occlusion?
if leg is spared = distal
proximal, leg will be equally affected with face and arm
monotonous but clear speech indicates
loss of parosody (emotional tone) and recognition of parosody
(non-dominant hemisphere function)
what type of stroke is characterized by the absence of cortical signs and hemiplegia/hemisensory loss face=arm=leg
lenticulostriate
supplies the basal ganglia structures
lenticulostriate arteries
can’t feel number traced on palm
graphesthesia
indicates **cortical sensory loss*
superior quadrantanopia/homonymous hemianopia
wernickes if dominant
left-sided neglect if non-dominant
cortical sensory loss
inferior MCA
Broca’s
gaze preference (FEF involvement)
hemiparesis face=arm > leg
foot is spared
superior MCA
contralateral weakness/numbness and UMN signs confined to the leg
fluent speech
no gaze preference
no visual defect
unilateral ACA
subfalcine herniation can cause bilateral […] occlusion
ACA
paraplegia of lower extremity sparing face and hands
incontinence
abullia
bilateral ACA
dense right visual field defect
poor short term memory
fluent speech
no gaze preferences
normal strength, sensation, reflexes
PCA
supplies blood to the thalamus
PCA
contralateral loss of all sensory
dense unilateral visual field defect with macular sparing [2]
occlusion of the PCA at thalamus
inferior MCA
inferior MCA occlusion can affect which visual radiation?
both
occlusion of […] can affect the RAS
PCA
occlusion of the ophthalmic artery can cause
amaurosis fugax
episodic unilateral vision loss
like a “shade” pulled over the eye
amaurosis fugax
(due to occlusion of the ophthalmic artery)
would occlusion of the MCA or PCA cause monocular blindness?
no
pure hemiplegia without cortical findings
lacunar infarct- lenticulostriate artery
Wernickes aphasia
visual field cut
inferior MCA
sudden contralateral leg weakness and sensory loss to all modalities
ACA
Brocas
weakness of contralateral face and arm
no visual field cut
superior MCA
bilateral visual loss (cortical blindness)
PCA-MCA watershed region
with signs of systemic hypoperfusion (e.g., tachycardia, low blood pressure, pallor, sweating)
proximal limb weakness with sparing of the face, hands, and feet (“man-in-the-barrel syndrome”)
ACA-MCA watershed region
with signs of systemic hypoperfusion (e.g., tachycardia, low blood pressure, pallor, sweating)
most likely mechanism of stroke with risk factors and non-flow limiting stenosis on the carotid arteries
artery-to-artery emboli
does unilateral carotid stenosis typically cause loss of consciousness?
no, would have to be bilateral to impair the RAS or cortex bilaterally
no risk factors or imaging evidence of atherosclerosis or lacunar disease
what’s the mechanism of the stroke?
cryptogenic
[…] is not indicated for the secondary prevention of ischemic stroke from atherosclerosis
warfarin