Pathology of Hypertension

Question 1

What can hypertension lead to?

Answer 1

• stroke
• atherosclerotic CV disease
• heart failure
• renal failure
• multi-infarct dementia

Question 2

What are the systolic and diastolic cutoffs for increased risk of ACD?

Answer 2

140 mm Hg and
90 mm Hg

lower with someone with diabetes and AA patients

Question 3

What causes hypertension?

Answer 3

• idiopathic (essential HTN) 90+%

- secondary causes such as renal disease, renal artery narrowing, adrenal disorders

Question 4

What are some rare single gene disorders that can lead to HTN?

Answer 4

• Aldosterone metabolism- leads to increased aldosterone, increased salt and water, and plasma expansion
• Sodium resorption

Question 5

Why would renal artery narrowing lead to HTN?

Answer 5

When the kidney thinks that there isn’t enough blood in the body (because it’s not getting any) it will increase BP

Question 6

What is the equation for cardiac output?

Answer 6

CO= HR (heart rate) x SV (stroke volume)

Question 7

Endothelial injury leads to what?

Answer 7

• smooth muscle growth
• matrix synthesis

both lead to lumenal decrease

Question 8

What is arteriosclerosis?

Answer 8

hardening of the arteries

Question 9

What happens in atherosclerosis?

Answer 9

LDL lipoproteins enter the intima following endothelial injury and they are taken up by macrophages leading to foam cells. Eventually the proteins and macrophages die, leaving a necrotic lipid dense core plaque with a fibrous cap over the top

atherosclerosis= lipid deposit

Question 10

What happens if the fibrous cap gets too thin?

Answer 10

the plaque can rupture and thrombi can form

Question 11

What is medical calcific sclerosis (Monckenbergs)?

Answer 11

incidental calcification in the media

Question 12

What is Arteriolosclerosis?

Answer 12

thickened walls in arterioles that is associated with hypertension and diabetes

Question 13

What are the types of arteriolosclerosis?

Answer 13

hyaline arteriolosclerosis and hyperplastic arteriolosclerosis

Question 14

What is hyaline arteriolosclerosis caused by?

Answer 14

increased pressure due to hypertension pushes the plasma proteins into vessel walls leading to increased ECM construction and the intima expands

Question 15

What is hyaline arteriolosclerosis associated with?

Answer 15

benign hypertension

Question 16

What can hyaline arteriolosclerosis lead to?

Answer 16

nephrosclerosis- eventually the kidney doesn’t have the proteins needed to function

Question 17

What is hyperplastic arteriolosclerosis associated with?

Answer 17

more severe hypertension (systolic over 200 mm Hg) that leads to an onion skinning appearance of the vessel caused by smooth muscle proliferation

Very high HTN can lead to fibrinoid deposits and vessel wall necrosis

NOT much inflammation here (distinguish from vasculitis)

Question 18

What is a complicated lesion?

Answer 18

when the fibrous cap of a plaque wears down, the lipid dense core can form a thrombus/embolus

Question 19

What causes aneurysm?

Answer 19

eventually the plaque will weaken the intima and media

Question 20

What are the constitutional risks of plaque formation?

Answer 20

• genetics
• age (silent until 40-60)
• gender- premenopausal women protective effect (estrogen?- possible)

Question 21

What are the acquried risks of plaque formation?

Answer 21

• hyperlipidemia
• HTN
• cigs
• diabetes
• inflammation (increased CRP)
• hyperhomocysteinemia

Question 22

Describe atherosclerosis.

Answer 22

• Chronic endothelial injury
• Accumulation of lipoproteins that diapedes into the intima
• Inflammatory response of monocytes come into the intima and eat the LDL to try to remove it
• Cytokines promote smooth muscle growth
• Macrophages eventually die leaving necrotic center
• Fibrous cap forms over lipid dense core
• Continued growth and remodeling

Question 23

What is an unstable plaque?

Answer 23

Occurs when 70-80% of lumen (critical stenosis) is obstructed and become more clinically evident and prone to rupture and embolus OR aneurysm

Question 24

What are common vessels affected by atherosclerosis?

Answer 24

• infrarenal abdominal aorta (very turbulent)
• Coronary arteries
• Popliteal arteries
• Internal carotid arteries
• Circle of willis

Question 25

Where is the vaso vasorum common?

Answer 25

aortic arch since it is so thick so it provides blood to the media and adventitia

Question 26

What causes thrombus formation following plaque formation?

Answer 26

breaking open of the fibrous cap causes hemorrhage which clots and forms a thrombus

Question 27

T or F. True aneurysms involve all three layers of the vessel wall

Answer 27

T.

Question 28

What is a dissection?

Answer 28

a tare in the intima due to problems with the media (usually vaso vasorum is messed up and cant get blood to the media) and its integrity is compromised or someone with collagen issues- ehlers dances, etc.)

Question 29

What causes aneurysm?

Answer 29

atherolsclerosis is a disease of the intima, however, in advance disease, the plaque compresses and thins the media, weakening the wall, causing a loss of elasticity leading to aneurysm

Question 30

What is the most common cause of an aneurysm of the ascending aorta?

Answer 30

HTN

Question 31

What is the most common cause of an aneurysm of the abdominal aorta?

Answer 31

atherosclerosis

Question 32

T or F. A patient with Ehlers- Danlos or Morfan’s syndrome is act high risk of aneurysm

Answer 32

T. No elasticity in media

Question 33

What can cause thoracic aneurysm?

Answer 33

Syphillis- plasma cells surround and inflame the vast vasorum, weakening the media