Atherosclerotic CNS stuff (Pales) Flashcards by Briana Tillman

Q

Epidemiology of Stroke

A

Third leading cause of death in the US

very common

deaths: black males> black females> white males> white females

leading cause of long-term disability in the US

high economic burden

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Stroke definitions

A

CVA (cerebrovascular accident)

abrupt onset of a neurological deficit that is attributable to a focal vascular cause

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

2 major types of stroke

A

Hemorrhagic (cerebral hemorrhage)- 15%

Ischemic (cerebral ischemia)- 85%

Ishemia– from Greek. Restriction of Blood

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

blood in the brain

A

is an irritant, causes swelling (in hemorrhagic stroke, cut a hole to let the brain swell)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Ischemic penumbra

A

brain tissue surrounding the cerebral necrosis that exhibits reversible ischemic changes (salvageable)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

causes of ischemic stroke

A

large artery thrombosis

embolism

Lacunar

Other (watershed infarcts, hypercoagulable disorders, vasculitis, vasospasm, dissection of artery, venous thrombosis, Moyamoya disease)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

large artery thrombosis

A

plaque with fibrous cap–> cap ruptures–> blood clot forms around the rupture, blocking the artery

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Embolic stroke- types of emboli

A

originating from an atherosclerotic plaque

originating from thrombus

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Sources of emboli

A

heart
artery to artery
lower extremity DVT with paradoxical emboli

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Cardiac emboli sources

A

Atrial: atrial fib/ flutter, atrial eptal aneurism, atrial tumors (myxoma)

Ventricular (cardiomyopathy, MI, ventricular aneurisms)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Atrial septal aneurism

A

weakening and out-pouching of interatrial septum, leading to stasis and thrombus formation (mural)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Atrial myxoma

A

pieces of tumor may tear off and become emboli

associated thrombus can embolize

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Ventricular sources of emboli

A

cardiomyopathy

infarction

ventricular aneurisms

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

cardiomyopathy

A

Weak and dilated ventricle isn’t pumping efficiently leading to blood stasis and thrombus formation

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

MI (as source of embolus)

A

part of the wall is not moving, creating stasis and leading to mural thrombosis

can be from current or old MI

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Cardiac emboli- valvular sources

A

rheumatic miral stenosis
prosthetic valves
infective and non-infective endocarditis
nonbacterial thrombotic (marantic- age-related) endocarditis associated with malignancies and prothrombic states
calcification of valves
bicuspid aortic valves
inflammatory valvulitis (Libman-Sacks, Behcet, Syphilis)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Artery to artery embolic infarcts

A

Carotid artery atherosclerosis/ stenosis- casues 5% of all strokes.
The tighter the stenosis, the higher the risk risk of stroke
May cause embolic or thrombotic type of strokes

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Paradoxical emboli

A

originate from the L.E. deep veins

“hole” in the heart between left heart and right heart

(PFO or ASD/ VSD)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Lacunar stroke

A

Infarct forms in ** subcortical** areas of brain supplied by small deep penetrating arteries arising from the big arteries

may be due to atheroemboli or lipohyalinosis (fibrous tissue replacing muscle around the lacunar arteries)

HTN is major factor

frequently asymptomatic (subcortex does very little, but basal ganglia can be affected)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Lipohyalinosis

A

high pressure of large arteries transmitted to small arteries

hyperplasia of small vessel walls

hyalinization of the vessel walls

narrowing and occlusion of the lumen

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Autoregulation of cerebral blood flow

A

the organs that are meant to die last when blood pressure falls: Brain and Kidneys. They have autoregulation.

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Watershed infarcts

A

Ischemic infarct of the areas farthest from the large arteries

the most sensitive areas when perfusion decreases

Develops with conditions causing hypotension

sepsis
severe bleeding
severe dehydration, etc.

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

Hypercoagulable disorders

A

Hemostasis system- 3 parts: coagulation system, anticoagulation system, thrombolytic system

hypercoagulable disorders promote coagulation over anticoagulation

most cause venous clotting but some favor arterial

examples:

Factor V Leiden mutation (most common)
Protein C deficiency
Protein S deficiency
Antithrombin deficiency
Plasminogen deficiency
Prothrombin gene mutation

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

disorders more likely to cause arterial clotting

A

antiphospholipid antibody syndrome .

Anticardiolipin antibodies (ACA)
Lupus anticoagulants (LA)

Hyperhomocysteinemia

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Other hypercoagulable states

Cancer (pancreatic, lung) pregnancy and exogenous estrogen use (including use of oral contraceptive pills-birth control pills) hormone replacement therapy prolonged bed rest or immobility, heart attack, stroke and other illnesses that lead to decreased activity myeloproliferative disorders such as polycythemia vera or essential throbocytosis

vasculitis

inflammatory condition --> thickening of arterial wall--> decreased lumen --> CNS restricted blood flow

Vasospasm causes

1. Cocaine (fries both cortices) | 2. After intracerebral bleeding (subarachnoid bleeding)

disection

often traumatic causes (golf, chiropractic, etc.)

Moyamoya disease

= "smoke puff" poorly understood. occlusive disease involving large intracranial arteries

Venous stroke

DVT in one of the venous sinuses may be ischemic or hemorrhagic usually associated with severe headaches and neurological symptoms

hemiparesis

weakness of one side of the body

hemiplegia

complete paralysis of one side of the body

homonymous hemianopsia (hemianopia)

loss of vision in the same visual field of both eyes

acalculia

difficulty to perform simple math tasks

agnosia

inability to recognize objects, persons, sounds, shapes, or smells

aphasia

inability to speak (motor or sensory)

alexia

inability to read

agraphia

inability to write

dysphagia

difficulty swallowing

dysarthria

slurred speech

hemispatial neglect

inability to attend to one side of the body or visual field

apraxia

inability to perform a specific task

anosognosia

unawareness of or denial of the existence of disability

anomia

difficulty with recalling words or names

ataxia

unsteady gait

MCA Syndrome

Contralateral hemiplegia/ sensation loss (sometimes in face and upper extremity only) contralateral homonymous hemianopsia Dominant side: aphasia, alexia, agraphia, acalculia, finger agnosia, and right-left confusion Non-dominant side: unilateral neglect, dressing apraxia, anosognosia, and constructional apraxia

ACA syndrome

Contralateral sensory and motor loss of lower extremity

PCA syndrome

Homonymous hemianopsia alexia without agraphia visual or color anomia

lateral pontine syndrome (Marie-Foix Syndrome)

anterior inferior cerebellar artery ataxia- arm and leg weakness- upper and lower extremity hemisensory loss- pain and temp

lateral medullary syndrome (Wallenburg)

``` Posterior inferior cerebellar artery Facial sensory loss and pain Ataxia Nystagmus Vertigo Hoarseness Dysphagia Horner syndrome Hemisensory loss Hiccups ```

Basilar artery strokes

Locked-in Syndrome - Quadriplegia, bilateral facial paralysis, dysarthria Lateral pontine syndrome (Marie-Foix Syndrome) Ventral pontine syndrome (Raymond Syndrome) - Lateral gaze weakness - Contraletaral hemiplegia Ventral pontine syndrome (Millard-Gubler Syndrome) - contralateral - upper and lower extremity weakness - Ipsilateral facial weakness Ataxic hemiparesis - Contralateral upper and lower extremity weakness and ataxia ``` Cortical blindness (Anton Syndrome) - (blindness and denial) ```

Other symptoms of stroke

headache nausea/ vomiting stupor/ coma/ amnesia/ confusion/ delerium

amaurosis fugax

transient mono-ocular blindness often warning sign of an impending stroke several causes: - embolic (most often from carotid artery of the same side) - hemodynamic - ocular - neurologic - idiopathic

opthalmic artery

is the first branch of the carotid before it goes to the brain thus amaurosis fugax is often the first warning sign of impending stroke

TIA

AKA "mini-stroke) the same symptoms (and detiology) as with stroke but lasting less than 24 hours 15-45% --> infarcts patients with TIA have 10% risk of CVA within first 3 months

Dx of stroke

History: sudden onset, symptoms described previously Complete neurological and mental status exam CT of brain (without contrast) is the quickest way- only detects big strokes. to R/O bleed (because we want to treat with blood thinners)-- takes 5 minutes MRI of brain is very sensitive-- takes 45 minutes

assessing the cause of stroke

``` History: look for risk factors lipids, blood glucose, cardiac enzymes EKG- arrhythmia, MI Echocardiogram (transthoracic or transesophageal)- intracardiac thrombosis, cardiomyopathy, valvular disorders, ASD Carotid Doppler- carotid stenosis MR-A/ CT-A ```

Differential Dx of ischemic stroke

``` hemorrhagic stroke/ subdural hemorrhages seizures complex migraines CNS tumors nerves palsy, peripheral neuropathy encephalitis toxic metabolic encephalopathy syncope vertigo ```

most common cause of mental status change in hospitalized patients

toxic metabolic encephalopathy

acute treatment of stroke

activation of STROKE ALERT TEAM (time is brain) medications - rtPA (intra-venous and catheter-directed intraarterial) - antiplatelet agents- ASA, clopidogrel, aggrenox (ASA/ dipiridamole) IV fluids heparin- select cases (known visible thrombus, dissection, staggering CVAs) - causes a lot of bleeding Keep BP sufficient for saving penumbra but not too high- permissive HTN Swallowing evaluation Early rehabilitation

clot buster rtPA works on

plasminogen--> plasmin

Stroke risk factors - modifiable

``` HTN Arial fib smoking diabetes carotid stenosis (increases risk 2 times if no previous TIA or CVA) Hyperlipidemia (increases risk 2-2.5 times) Physical inactivity and obesity Alcohol and drug abuse Geographic location US South-East has more strokes Socioeconomic factors ```

stroke prevention

Diet- low in sat fat exercise- aerobic exercises 30-60 minutes/ day, most days Strict control of Blood Pressures, Blood sugars, blood cholesterol Quit smoking meds: - antiplatelets. Aspirin, clopidogril - anticoag agents: warfarin, heparin and LMWH, new oral anticoag drugs: dabigtran, rivaroxaban, apixaban, edoxaban

treatment options of carotid stenosis

depends on degree of stenosis and on h/o CVA medical treatment (treat risk factors) surgical treatment with carotid endarterectoy stents - only for lesions not reachable with surgical approach - Patients have high surgical risk

carotid endarterectomy

atherosclerotic plaque removed from carotid artery to restore blood flow to brain

Stroke Risk FactorsNon-modifiable

Age. - Risk doubles with each decade after 55 Heredity (Family history) Race - African Americans and Hispanics higher than Caucasians Gender - More men has strokes in a given year in each age group - More than half of total stroke deaths occur in women Personal h/o TIA, CVA, MI, any atherosclerosis

Ischemic stroke - general

extremely common cause of death and disability in the US There are multiple causes of ischemic stroke; embolic, lacunar and thrombotic being the most common ones In both TIA and CVA it’s important to know the type of stroke and the source of emboli, as it will determine the acute treatment and the means for secondary prophylaxis

Atherosclerosis and Hypertension

are major risk factors for strokes. Hypertension is the main cause of lacunar (small vessel) strokes. Symptoms of the stroke depends on the location and size of the vessel involved

TIA

a transient ischemia or small CVA when all symptoms are resolved within 24 hours. The same patient may have several CVAs of different etiology as the risk factors for different conditions are similar. Always look at the patient’s symptoms and match them with the stroke location on MRI

If location of stroke is in the territory of more than one particular artery, think

embolic and think about the source upstream It’s always important to consider differential diagnosis

CT of the brain

is used for diagnosing large strokes and to r/o bleeding for tPA administration, but may miss early strokes, especially if it’s small or in posterior circulation.

tPA

is a one of the major treatment of the ischemic stroke, but full of complexities and controversies