Vascular Neurology 2: Ischemic Stroke

Question 1

Percentage of strokes that are ischemic? Hemorrhagic?

Answer 1

Ischemic: 80%
Hemorrhagic: 20%

Question 2

Old vs. new definition of TIA?

Answer 2

Old: Neurological symptoms resolve within 24 hours.
New: Neurological symptoms that resolve AND no evidence of permanent damage on scan.

Question 3

What small arteries run from the MCA to the basal ganglia, internal capsule, thalamus, etc.? What is an infarct of these vessels called?

Answer 3

Lenticulostriate arteries. Infarct = lacunar stroke

Question 4

Name 5 classic lacunar syndromes.

Answer 4

Pure motor hemiparesis
Sensori-motor stroke
Pure sensory stroke (note similarity of first 3)
Dysarthria-clumsy hand syndrome
Ataxic hemiparesis

Question 5

What must be absent in order to diagnose a lacunar stroke? (2 things)

Answer 5

Cortical signs

Visual field involvement

Question 6

When do you look for less common causes of stroke?

Answer 6

Young patients without common risk factors.

Question 7

What is arterial dissection? How can it cause stroke?

Answer 7

Tear in blood vessel intima.

Exposed tissue is highly pro-thrombotic -> thromboembolus cause stroke.

Question 8

Most significant modifiable risk factor for stroke?

Answer 8

Hypertension

Question 9

What does a prior history of heart problems such as atrial fibrilation suggest about the possible cause of a patient’s stroke?

Answer 9

May be cardioembolic.

Question 10

List stroke mimics. There are 9… (probably not the highest yield thing to spend your time on)

Answer 10

Seizure, migraine, hypo/hyperglycemia, other metabolic derangements, drug OD, head/neck trauma, intracranial mass, meningitis/encephalitis, and psychogenic.

Question 11

Can you see an early ischemic stroke on a CT scan?

Answer 11

Yes, sometimes. (though not always) It’s more subtle than how a hemorrhagic stroke appears, but you can sometimes see a loss of grey/white matter differentiation.

Question 12

What’s the most sensitive imaging modality for detecting an ischemic stroke? What does it show you?

Answer 12

Diffusion weighted MRI. Shows abnormal water movement in dying cells.

Question 13

4 parts of acute care for (ischemic) stroke?

Answer 13

Reperfusion (thrombolysis)
Neuroprotection
Prevent recurrence (antithrombotic drugs)
Supportive care

Question 14

2 variables determining how much damage is done during ischemic stroke?

Answer 14

Degree of blood flow reduction.

Time that it stays low.

Question 15

What is the core/penumbra concept of ischemic stroke?

Answer 15

Core is the area hit first. You can’t do much about it. Penumbra is the surrounding range of affected cells that can be saved if the stroke is reversed.

Question 16

What’s the drug of choice for ischemic infarct?

Answer 16

t-PA (tissue plasminogen activator)

Question 17

Major drawback of t-PA? How many people have this bad outcome? What usage guidelines are made for this reason?

Answer 17

High risk of intracerebral hemorrhage (ICH)
1 in 15 people (6%)
Must give t-PA within 4 hours of symptoms (i.e. when benefit outweighs risk)
Don’t give to people with risk factors for ICH.

Question 18

What is an alternative to t-PA for busting clots in ischemic stroke? Time window for use?

Answer 18

Mechanical thrombolysis (the spiral, roto-rooter things).
8 hours.
Could theoretically be used for people with ICH risk factors, but “their role is controversial.”

Question 19

Is heparin used to prevent the recurrence of ischemic stroke?

Answer 19

Nope. Causes too many bleeds to produce a net benefit.

Question 20

Choice of antithrombotic drug for ischemic stroke prevention varies with the cause of the stroke. What drugs are used for which types? Why the difference?

Answer 20

Cardioembolic: Anticoagulant drugs (e.g. warfarin)
Everything else: Antiplatelet drugs (e.g. aspirin, Plavix)
Anti-platelet drugs are safer and easier to use.

Question 21

With recurrent TIAs, what does the localization tell you about the underlying cause?

Answer 21

Same location: Probably large vessel disease (e.g. carotid stenosis)
Different locations: Probably cardioembolic.

Question 22

What score is used to estimate the risk for stroke after TIA? Variables in the score?

Answer 22

ABCD^2
Age
Blood pressure
Clinical features (unilateral weakness, aphasia)
Duration
Diabetes

Question 23

Do venous thrombosis symptoms respect vascular territories?

Answer 23

Nope.

Question 24

5 signs/symptoms of venous thrombosis.

Answer 24

Sudden focal deficits, seizures, headache, encephalopathy (a uselessly vague term?), and papilledema.

Question 25

Why does venous thrombosis cause both infarct and hemorrhage?

Answer 25

Increased venous pressure prevents perfusion, arterial blood hemorrhages because it has nowhere else to go…

Question 26

Treatment of cerebral venous thrombosis?

Answer 26

Anticoagulation with heparin. (contrast with treatment for arterial ischemic infarct)
Prof. notes local infusion of thrombolytic agents and mechanical thrombolysis as up-and-coming therapies.

Question 27

time = ?

Answer 27

brain