(MHD) Vascular Heart Disease Flashcards
Describe the intimal response to vascular injury.
In vascular injury there is smooth muscle cell deposition in the subendothelium and these smooth muscle cells secrete ECM, causing an increase in size of the subendothelium. This makes it more difficult for blood vessels to receive nutrition from vaso-vasorum.
What is arteriosclerosis? List the (3) types.
Hardening of the arteries (arterial wall thickening and loss of elasticity)
- Atherosclerosis
- Monckeberg’s medial calcific sclerosis
- Arteriosclerosis- hypertension induced
What vessels are more likely to be affected by atherosclerosis? Which ones are rarely affected?
Larger elastic arteries (aorta, carotid, Iliac)
Renal/mesenteric etc. are much more rare
Describe the “Response to Injury” Hypothesis
It states that atherosclerosis is a chronic inflammatory response of the arterial wall to endothelial injury.
What is an atheroma?
An atheroma is an accumulation of degenerative material in the tunica intima (inner layer) of artery walls. The material consists of (mostly) macrophage cells, or debris, containing lipids (cholesterol and fatty acids), calcium and a variable amount of fibrous connective tissue. The accumulated material forms a swelling in the artery wall, which may intrude into the channel of the artery, narrowing it and restricting blood flow.
An atheroma is a basic pathologic finding for ___________ blood vessels.
Atherosclerotic
Describe the (2) main components of an atheroma
- Fibrous cap- smooth muscle, macrophages, elastin, etc.
- Necrotic Center- cell debris, cholesterol, calcium, etc.
How can an atheroma lead to ischemia/aneurysm?
As the atheroma grows the media becomes stretched and more prone to ischemia because luminal blood can’t reach it and vaso vasorum blood can’t reach as well. This ischemia leads to atrophy and wall weakening, which potentially leads to aneurysm.
This image histological image is indicative of what?
An atherosclerotic cholesterol embolus. You see needle shaped spaces because the cholesterol falls out during the staining process.
What is Monckeberg’s Medial Calcific Sclerosis? How obstructive is it?
It is a form of arteriosclerosis in which there are calcium deposits in the media of medium sized muscular arteries. This is a non-obstructive disease.
Name the (2) types of hypertension induced arteriosclerosis
- Hyaline arteriolosclerosis
- Hyperplastic arteriolosclerosis
Hyaline arteriolosclerosis
1 of 2 hypertension induced arteriosclerosises
Due to long standing hypertension which injures the endothelial cells, these patients have a plasma protein leakage into the blood vessel wall. This causes significant lumenal narrowing.
Hyperplastic arteriolosclerosis
1 of 2 hypertension induced arteriosclerosises
Caused by a very severe and acute BP elevation. Smooth muscle cells respond to this increase by thickening and duplicating their layers, creating characteristic “onion skin” concentric thickening.
False aneurysm
When there is damage to the vascular wall and blood is leaking into the extravascular connective tissue forming a hematoma. Can appear as an aneurysm on CT but is not a true aneurysm.
Cystic Medial Degeneration
Degradation of elastin and smooth muscle which leads to “cystic-like” spaces in the vessels. Causes weakness and can lead to aneurysm.
Type A vs Type B Aortic Dissection
Which one is more serious?
Type A: Involves proximal aorta
Type B: does not involve proximal aorta
Type A is an emergency and requires immediate operation.
