The Student Room Group

Atherosclerosis / Coronary Heart Disease

Cholesterol is deposited in the arteries, the build up reduces the size of the lumen, restricting blood flow, starving the heart of oxygen.

One book/ answer says that answering "blood vessels get blocked" is too vague, why?

I thought maybe because only arteries get blocked - because of the pressure of the blood?
The coronary artery is the vessel which gets blocked, (The left coronary artery is the vessel most likely to get blocked/ and the LAD is the most bypassed vessel...

So the oxygenated blood under higher pressure circulates around and cholesterol deposits on the closest artery, Im guessing this is the left coronary artery after branching from the Aorta?, and there maybe be some deposition in the aorta? (But due to the relative size - this causes no problems?

I don't think this level of detail is needed at A Level, just curious, any help understanding is appreciated :smile:

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Same reasoning for hypertension?
Increased pressure = more damage to arteries?
(edited 12 years ago)
Reply 1
yep i'm pretty sure all arteries can get atherosclerosis, the size depends how much affect the plaque build up has. So coronary arteries get affected as tiny but necessary, cerebral arteries also get affected = stroke, kidney arteries can get affected, erm it can also cause retinopathy.... and theres probably more areas atherosclerosis commonly affects (in terms of causing symptoms) that i'm not thinking of :smile:
Reply 2
Original post by halfadoc
yep i'm pretty sure all arteries can get atherosclerosis, the size depends how much affect the plaque build up has. So coronary arteries get affected as tiny but necessary, cerebral arteries also get affected = stroke, kidney arteries can get affected, erm it can also cause retinopathy.... and theres probably more areas atherosclerosis commonly affects (in terms of causing symptoms) that i'm not thinking of :smile:


Okay thank you
it can effect any, typically larger, arteries but particular locations are of note because of the problems they cause e.g the arteries to the limbs (typically femoral) for peripheral artery disease the coronary arteries for angina, the renal arteries for stenosis leading to hypertension. The most common site for lesions to start is at branching points, for example the biforcation of the internal and external carotid arteries from the common carotid (very important for stroke risk).

the fact the coronary arteries have been highlighted is because of the low level of collateral circulation and their importance to normal physiology, the heart in general is not particularly well vascularised at best. it is not the only place as you suggest in your piece though, the aortic lesions are important and deposition in other areas is important as dictated above. what causes lesions to develop is not conclusively pressure if that's what you've been taught, there is a strong drive to presume that it is important (the 'response to injury hypothesis' of the 70s) but how these lesions actually start and why in a particular location is not as clear as some people make out.

i don't know what you mean by same reasoning for hypertension. hypertension is a very different disease with an equally debatable pathogenesis. the only way in which atherosclerosis and hypertension interact in a pathogenic sense is via renal artery stenosis discussed above.
Reply 4
Original post by ieatcheeseyo
Cholesterol is deposited in the arteries, the build up reduces the size of the lumen, restricting blood flow, starving the heart of oxygen.

One book/ answer says that answering "blood vessels get blocked" is too vague, why?

I thought maybe because only arteries get blocked - because of the pressure of the blood?
The coronary artery is the vessel which gets blocked, (The left coronary artery is the vessel most likely to get blocked/ and the LAD is the most bypassed vessel...

So the oxygenated blood under higher pressure circulates around and cholesterol deposits on the closest artery, Im guessing this is the left coronary artery after branching from the Aorta?, and there maybe be some deposition in the aorta? (But due to the relative size - this causes no problems?

I don't think this level of detail is needed at A Level, just curious, any help understanding is appreciated :smile:

Same reasoning for hypertension?
Increased pressure = more damage to arteries?



ummmm......atherosclerosis = hardening of arteries. The site of occurrence determines the disease. coronary heart disease = coronary artery (this might lead to Myocardial Infarction, Angina Pectoris [severe chest pain] or Heart failure [gradual weakening of the heart muscle]).
Original post by djay x-pro
ummmm......atherosclerosis = hardening of arteries. The site of occurrence determines the disease. coronary heart disease = coronary artery (this might lead to Myocardial Infarction, Angina Pectoris [severe chest pain] or Heart failure [gradual weakening of the heart muscle]).


no... 'hardening' of the arteries (ie. the loss of compliance) is arteriosclerosis which is linked to aging and a completely different pathology (cf. thickening of the media vs. the intima in athero). coronary heart disease is not just atherosclerosis of the coronary vessels but this is one of the most common causes (ie. a heterogeneous anatomically described disease).
You might want to mention how the cholesterol gets deposited (look up HDLs and LDLs)
Reply 7
Original post by John Locke


i don't know what you mean by same reasoning for hypertension. hypertension is a very different disease with an equally debatable pathogenesis. the only way in which atherosclerosis and hypertension interact in a pathogenic sense is via renal artery stenosis discussed above.


If i'm right about what I think OP means about hypertension then i'm pretty sure they are right - whilst they are different diseases they are certainly linked, hypertension in itself causes no symptoms, its the conditions it pre disposes you to that cause the problem. I believe OP meant that hypertensive patients are more likely to have atherosclerosis which is true not only cause of the renal artery stenosis you mentioned but because Hypertension = more likely for arteries to get damaged (as pressures increased even more than normal) = more likely to have a greater degree of atherosclerosis = more likely to get angina/ MI.


I've just double (google) checked this to check I'm not talking nonsense :http://www.webmd.com/hypertension-high-blood-pressure/guide/atherosclerosis and lots more saying the same thing :smile:
Original post by halfadoc
If i'm right about what I think OP means about hypertension then i'm pretty sure they are right - whilst they are different diseases they are certainly linked, hypertension in itself causes no symptoms, its the conditions it pre disposes you to that cause the problem. I believe OP meant that hypertensive patients are more likely to have atherosclerosis which is true not only cause of the renal artery stenosis you mentioned but because Hypertension = more likely for arteries to get damaged (as pressures increased even more than normal) = more likely to have a greater degree of atherosclerosis = more likely to get angina/ MI.


I've just double (google) checked this to check I'm not talking nonsense :http://www.webmd.com/hypertension-high-blood-pressure/guide/atherosclerosis and lots more saying the same thing :smile:


i'll yield that i misunderstood what the OP meant about HTN, i thought they meant the same as in how HTN starts rather than HTN as a risk factor for atherosclerosis which is very true.

the bit i've put it bold is certainly not that simple! whilst hypertension does predispose i don't think you can just argue its because of endothelial damage, there is also profound endothelial dysfunction and a variety of other things that could be involved. Furthermore progression of plaques is not just dependent on blood pressure so it's not as prediction of the extent of a lesion.

a word of warning on citing webMD as evidence, whilst what you said was okay that doesn't offer any kind of evidence to support it!

thanks for making it clear though :smile:
Reply 9
Lol don't worry I do know its not that simple but I believe OP is an a level student and doesn't need to know more than the core idea :smile:, also just thought webMD gave a good simple explanation of the core concept wasn't saying is was proof but not sure a vancouver referenced pubmed article was needed here :P, obviously I wouldn't suggest using webMD for an essay.
Original post by Dragonfly07
You might want to mention how the cholesterol gets deposited (look up HDLs and LDLs)


HDL's transport cholesterol from tissues to Liver. Reducing the blood cholesterol level
LDL's tranport cholesterol from the liver to the tissues. Increasing the blood cholesterol level

Sat fats = LDL's = More chance of CHD
Unsat fats = HDL's = "Less chance" of CHD

Anything else at AS?
Original post by halfadoc
If i'm right about what I think OP means about hypertension then i'm pretty sure they are right - whilst they are different diseases they are certainly linked, hypertension in itself causes no symptoms, its the conditions it pre disposes you to that cause the problem. I believe OP meant that hypertensive patients are more likely to have atherosclerosis which is true not only cause of the renal artery stenosis you mentioned but because Hypertension = more likely for arteries to get damaged (as pressures increased even more than normal) = more likely to have a greater degree of atherosclerosis = more likely to get angina/ MI.


I've just double (google) checked this to check I'm not talking nonsense :http://www.webmd.com/hypertension-high-blood-pressure/guide/atherosclerosis and lots more saying the same thing :smile:


Is/are vessels affected by hypertension the arteries only, because of the increased pressure?
Deposition is mostly in the Left coronary artery because of it's position, relative diameter... the veins don't have much deposition due to the relatively lower pressures of the blood as they travel back to the heart right?

So is hypertension something that only affects the arteries?
And after hypertension (the early stages of CHD, HT increases the chances of CHD?

(Sorry it''s worded poorly)
Reply 12
Original post by John Locke
no... 'hardening' of the arteries (ie. the loss of compliance) is arteriosclerosis which is linked to aging and a completely different pathology (cf. thickening of the media vs. the intima in athero). coronary heart disease is not just atherosclerosis of the coronary vessels but this is one of the most common causes (ie. a heterogeneous anatomically described disease).


thanks, bro, only that 'google' said it so i decided it was right....

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