Lecture 16 and 17 -- CVD

Question 1

what are two types of stroke

what is the only way to differentiate the two?

Answer 1

Hemorrhagic and Ischemic

Imaging

Question 2

what are the two types of hemorrhagic stoke?

what imaging type is best for to see a hemorrhagic stroke

Answer 2

SAH

ICH

CT scan – quick and good for fluid

Question 3

underlying causes of SAH

Answer 3

Berry Anuerysm – ballooning of an artery, weakening of the wall; typically in the branch points of Ant. Comm artery

Arterio-Venous Malformation – abnormally direct communication between arteries —> Veins without intervening capillary bed. Venous system exposed to high arterial pressures.

Question 4

underyling causes of ICH?

Answer 4

HTN – long standing atheroscloerosis

Cerebral Amyloid Angiopathy – degenerative deposition of Amyloid in aterial walls of cortical vessels

Aneurysm, AVM

Question 5

Treatment of hemorrhagic stroke?

Answer 5

Medical emergency; ICU; Neurosurgery consult

do not give TPA

Question 6

Clinical defition of an ischemic stroke?

what imaging is used to view acute ischemic stroke?

Answer 6

Clinical manifestation of a CNS Infarcton
Sudden onset, focal deficits lasting > 24 hours
evidence of infarctioin on imaging

diffuse weighted MRI (this will not show up on CT)

Question 7

brain’s compesnation mechanisms for reduced blood flow…

Answer 7

Vasodilation – increased transit time

Anaerobic metabolism – but when all energy resoruces depleted….

electrical failure — TIA, stroke

Question 8

what is a TIA

how should it be managed clinically

Answer 8

TIA – transiet ischemia attach
transiet focal neurological deficits
No actual infarction
Technically TIA if symptoms last less than 24 hours (but in reality if symptoms last more than 2 hours, they are going to last more than 24 hours)

Warning sign for acute ischemic stroke; should not be ignored

Question 9

ischemic penumbra vs ischemic core

Answer 9

penumbra: reversbile infarction

Core: irreversible

core grows with time
time = brain

Question 10

rank the following in regards to sensitivity to ischemia from least to most:

oligodendrocytes, neurons, endothelium, astrocytes

Answer 10

Least: Endothelial cells

astro

Oligo

Neurons (hippo, purkinje cells, pyramidals of cortex, neostriatum)

Question 11

what are 4 ways in which patients can deteroirate in the setting of ischemic stroke

Answer 11

Cytotoxic Edema –

Hemorrhagic Conversion

Herniations

Recurrent ischemic stroke –

Question 12

Cytotoxic edema

pathophysiology –

how does this kill you?

how can this be alleviated?

Answer 12

Increased permeability of neuronal and glial cell membranes results in intracellular swelling

Kills you - – mass effect–> herniation

Alleviated – Hemicraniectomy

Question 13

Review of imaging for storkes:
hemorrhagic?
acute ischemic?
cytotoxic edema?

Answer 13

CT

Diffusion weighted MRI

CT

Question 14

Hemorrhagic COnversion -- 
what is it? 
difference between large and small strokes? 
how does it kill you?
alleviate this?

Answer 14

Friable endothelium; blood leaks out into parenchyma upon reperfusion

Large stroke – parenchyma is dead and therefore will not be symptomatic

Small stroke - parenchyma is viable; reperfusion will lead to further damage == symptoms

Kills you — herniation

alleviate this – hemicraniectomy

Question 15

hemicraniectomy differences between and outcomes for lesions above the tentorium and below the tentorium

Answer 15

above the tentorium – slower deterioration; hemicraniectomy will save your life but you have had a massive stroke; therefore quality of life outcomes poor as patients have significant neuro deficits

below the tentorium (cerebellum) – can deteriorate very quickly without intervention; but following hemicraniectomy, outcomes are good becuase of redundant wiring of the cerebellum

Question 16

Treatment for ishcemic stroke

Answer 16

TPA (alteplase)

Mechanical Clot Extraction Devices

Question 17

Know anterior vs posterior vascular lesions and manifestations; esp regarding vision

Example:
Isolated Homonymous hemianopia = ?

Unilateral monocular blindness = ?

Answer 17

Isolated Homonymous hemianopia = PCA

Unilateral monocular blindness = Ophthalamic artery

Question 18

Etiologies and subtypes of ischemic stroke ***

Answer 18

atherothrombotic cerebrovascular disease

Penetrating artery Disease – Small artery Disease – Lacunar Stroke

Cardiogenic Embolism

Other unusual Stroke

Idiopathic – 20 to 40%

Question 19

atherothrombotic cerebrovascular disease

what vessels?
how can this be visualzed?
pathogenesis

Answer 19

Arterial Stenosis in the Head or Neck (Large intra cranial arteries; Extra cranial – carotid arteries)

Artery to artery Emboli
Stenosis –> slowed blood –> thrombus –> Embolism

Question 20

treatment of atherothrombotic cerebrovascular disease -

Answer 20

l Carotid Endarterectomy –

Angioplasty Stenting –

Question 21

Penetrating artery Disease – Small artery Disease – Lacunar Stroke

what vessels?
pathology of these vessels –

Answer 21

Base of brain, lenticulostriates, cerebellum

Lipohyalnaosis – thickening of the vessel wall, but its weak

Antherosclerosis

Question 22

Manifestations of Penetrating artery Disease – Small artery Disease – Lacunar Stroke

Answer 22

Deep penetrating arteries — therefore don’t have cortical deficits

Lacunar clinical Syndromes — No Cortical Dysfunction:
Pure Motor Hemiparesis — no sensory findings, visual findings

Pure hemi-sensory loss — just sensation

Question 23

Cardiogenic Embolism

most commonly?
imaging?

Answer 23

AFIB
Mechanical heart valves, Acute MI, Abn heart valves, Endocarditis

acute infarcts on MRI that are on both hemipshers, anterior and posterior

Question 24

treatment and previton of Cardiogenic Embolism

Answer 24

Treatment – TPA

Prevention – Full does Anticoagulation
Wafarin (VKOR1)
Dabigitran (direct thrombin)
Rivorxaban/Apixaban (direct 10a)

Question 25

antiplatelet therapies

Answer 25

ASA
Plavix
Aggrenox – ASA/Extended release dipyridamole

Question 26

Non modfiable risk factors

Answer 26

Age — exponential increase; although any age can get a stroke
Gender – post menopausal women (lower estrogen)
Race – African Americans
Prior stroke –

TIA

Question 27

Modifiable risk factors

most easily modifiable?

Answer 27

Afib – Warfarin;
Stenosis of Internal carotid Artery – HTN – 30-40% reduction in stroke when HTN is controlled Tobacco Use – Framhingham HLD –atherothrombotic stroke; vascular disease elsewhere
DM

Most easily modifiable – HTN and Tobacco