pathophysiology of atheroma Flashcards
what is atheroma/ atherosclerosis?
formation of focal elevated lesions (plaques) in intima of large and medium-sized arteries
what does atheroma lead to when the lumen of arteries is narrowed?
ischaemia
what does myocardial ischaemia from atheroma lead to?
angina
what is arteriosclerosis?
age-related change im muscular arteries that causes smooth muscle hypertrophy, apparent redulpication of internal elastic laminae, intimal fibrosis that causes a decrease in vessel diameter
what sorts of ischaemia can be caused by arteriosclerosis?
cardiac, cerebral, colonic and renal
when does arteriosclerosis become clinically apparent?
when cvs is further stressed by haemorrhage, major surgery, infection, shock
what is the earliest lesion present in atheroma?
a fatty streak, yellow linear elevation of lipid-laden macrophages
in what age of patients are fatty streaks (earliest significant lesion of atheroma)?
young children
what is the stage of atheroma prior to fully developed atheromatous plaque?
early atheromatous plaque
what are the characteristics of an early atheromatous plaque?
smooth yellow patches in intima, lipid-laden macrophages
describe the composition of a fully developed artheromatous plaque
central lipid core with fibrous tissue cap, covered by arterial endothelium
what does collagen in the fibrous cap of an atheromatous cap do?
provides structural strength to the structure
what is the core of an atheromatous plaque made from?
it is risch in cellular lipids/debris from macrophages
what is often found around the rim of the atheromatous plaque?
foamy macrophages
what often forms in late development of artheromatous plaques?
dystrophic calcification
where are atheromatous plaques most likely to form?
at arterial branching points/bifurcations
what are some features of complicated atheroma?
haemorrhage into plaque which can then calcify, plaque rupture/fissuring ,thrombosis
what is the most important risk factor form atheroma?
hypercholesterolaemia
what is the congenital abnormality that can cause primary lipidaemia?
lack of cell membrane receptors for LDL, carriers affected, homozygous individuals affected more severely
what is the familial form of hyperlipidaemia called?
primary hyperlipidaemia