82. Atheroma/Atherosclerosis Flashcards
name some atheroma synonyms
atherosclerosis
hardening of the arteries
coronary artery disease
ischemic heart disease
atheromas are extremely common in……………….world
developed
ichaemic heart disease and stokes account for …… of all deaths
1/3
what is the epidemiology of atheroma (aetiology)
- cigarette smoking
- hypertension
- hyperlipidemia
- diabetes
- age
- sex - males
- genetics
endothelial injury
what is the main ‘how’ of atheromas
endothelial injury or anything that increases endothelial cell injury can initiate the process of atherosclerosis
what kind of blood flow in vessels is said to be smooth in parallel layers
laminar
where does haemodynamic injury occur
- sites of turbulent flow
- any branching site - change of flow (aka not laminar)
Smoking a pack of cigarrettes a day increased the risk of angina etc. by over …………
200X
does high or low blood pressure damage endothelium
HBP
what is one of the biggest risk factors of atheromas
Hyperlipidemaemia
name a type of hyperlipidaemia
hypercholesterolaemia
High density Lipoprotein - good or bad?
Good
Low Density Lipoprotein - good or bad?
Bad
diabetes causes an increase of what
cholesterol levels
what is it that causes elastci strands in blood vessels to become rigid (diabetes)
advanced glycation end products (AGE)
what does Advanced Glycation End Products (AGE) cause
abnormal cross linking
loss of elasticity
trap cholesterol (LDL)
What is abnormal cross linking
They induce abnormal cross-linking of collagen and other proteins in the vessel walls. This cross-linking makes the vessel walls more rigid and less elastic.
what age is most at risk of atheromas
40-60
what age is earliest atherosclerosis started and what age is all started to develop
1 and then 10
why are males at higher risk
No one knows for sure as its an “independent risk factor”
genetic variation in what 3 areas can cause atheromas
- 1 – cholesterol metabolism
- 2 – inflammatory response
- 3 – control of blood pressure
in 4 steps describe how atheromas happen
- Primary endothelial injury
- Accumulation of lipids and macrophages
- Migration of smooth muscle cells
- Increase in size
when endothelial injury occurs what happens in terms of WBCs and perm… and (Hint- VC..)
increase permeability and increased WBC adhesion
increase VCAM-1: Vascular Cell Adhesion Molecule-1
In the blood stream they are called ………..and not in blood stream they are called …………….
In the blood stream they are called Monocytes and not in blood stream they are called macrophages
after endothelial injury, what attaches and migrates through wall
monocytes and once they are through they are macrophages
what do the macrophages do to the cholesterol
gobble it up
when the Macrophages ingest LDL cholesterol and can become …….cells if overloaded.
foam
when the Macrophages ingest LDL cholesterol and can become overloaded foam cells what happens to them
they become trapped and LDL is deposited in the arterial cell wall
what does the HDL do
High-density lipoprotein (HDL) cholesterol helps remove excess cholesterol from macrophages and other cells. HDL transports cholesterol back to the liver, where it can be processed and excreted from the body.
smooth muscle migrates from where to where
tunuica media into intima
when smooth muscle cells are migrating they get ……………… and take on………
stuck and take on cholesterol
after smooth muscle gets stuck and takes on cholesterol, what does it produce
Extracellular matrix - eg. Collagen
after smooth muscle gets stuck and takes on cholesterol and starts to produce ECM like collagen, what does it change from - to
Changes lesion from fatty streak to fibrofatty plaque
on a histogram how can you tell if something is skeletal muscle
striations
describe progression of an atheroma
- More cholesterol
- More macrophages
- More smooth muscle and collagen etc
Eventually too much cholesterol and a pool of extracellular cholesterol forms the centre of the plaque
what is the Poiseuille equation
Q= (Pi)(Pr^4) over (8)(n)(l)
Q - flow rate
P - pressure
r- Radius
n- Fluid Viscosity
l- Length of tubing
what is this equation called
Q= (Pi)(Pr^4) over (8)(n)(l)
Poiseuille
As atheromatous plaques enlarge blood flow is ….
compromised
Progression is associated with further loss of ………. and …………
luminal patency (the state of being openness obstructed) and arterial wall weakness
Whats the difference between fatty streak and fibrofatty plaque
Fatty Streak: Early, simpler lesions mainly composed of foam cells.
Fibrofatty Plaque: More advanced, complex lesions with additional cellular and extracellular components, and a higher risk of causing clinical problems.
ATHEROMATOUS NARROWING OF AN ARTERY IS LIKELY TO PRODUCE CRITICAL DISEASE IF
- It is the only artery supplying an organ or tissue (i.e. There is no collateral circulation)
- The artery diameter is small (e.g coronary artery versus common iliac artery)
- Overall blood flow is reduced (i.e. cardiac failure)
what is a proliferative atheroma
cells proliferate and extracellular matrix production causes plaque growth
what is a complicated atheroma
plaque rupturing - thrombosis etc
