atherosclerosis

Question 1

define atherosclerosis

Answer 1

the accumulation of fibrolipid plaques in systemic (not pulmonary) arteries

Question 2

why does atherosclerosis cause illness

Answer 2

reduces the blood blow to important areas eg the heaft

Question 3

time course of atherosclerosis

Answer 3

*birth - no atherosclerosis
* late teenage/early 20s - fatty streaks in aorta, may not progress to established atherosclerosis
* 30s/40s/50s - development of established atherosclerotic plaques
* 40s-80s - complications of atherosclerotic plaques e.g. thrombosis, intraplaque haemorrhage

Question 4

risk factors for atherosclerosis

Answer 4

• hyper tension
• hyperlipidaemia
• cigarette smoking
• poorly-controlled diabetes mellitus

Question 5

pathogenesis of atherosclerosis

Answer 5

old discredited lipid insudation theory
current endothelial damage theory

• endothelial cells are delicate
• easily damaged by cigarette smoke, shearing forces at arterial divisions, hyperlipdaemia, glycosylation products
  *cumulative damage leads to endothelial ulceration, mi- crothrombi, eventual development of established athero- sclerotic plaques

Question 6

what happens if an atherosclerotic plaque completely blocks an artery

Answer 6

(usually by superadded throm- bosis or haemorrhage within the plaque)

then no blood will flow to the organ supplied by that artery and (unless there is a second arterial supply which is unusual in the body) the organ will die (infarct)

Question 7

impact of embolism on atherosclerosis

Answer 7

Sometimes pieces of an atherosclerotic plaque can break o” and travel downstream to block smaller vessels - embolism

this may cause small infarcts distal to the main atheroscle- rotic plaque and over time these cumulative e”ect of these small infarcts can be significant.