Pathophysiology of atheroma Flashcards
Define atherosclerosis/atheroma
Formation of focal elevated lesions (plaques) in the intima of large and medium-sized arteries
Define arteriosclerosis
Age related change in muscular arteries
Smooth muscle hypertrophy leading to decreased vessel diameter, causes ischaemia
Describe a fully developed atheromatous plaque
Central lipid core with fibrous tissue cap, covered by arterial endothelium
What are foamy macrophages?
Foamy due to uptake of oxidised lipoproteins via specialised membrane bound scavenger proteins
Where are atheromatous plaques more likely to be found?
Areas of turbulent blood flow e.g. arterial bifurcations
State some causes of atheroma
Hypercholesterolaemia
Hyperlipidaemia
What type of cholesterol is important in hypercholesterolamia and atheroma?
LDL cholesterol
State 3 clinical signs of hyperlipidaemia
Corneal arcus
Tendon xanthomata
Xanthelasmata
State some major risk factors for atheroma
Smoking High cholesterol Hypertension DM Male Age/elderly
State some mind risk factors for atheroma
Obesity Sedentary lifestyle Low socioeconomic status Low birthweight Role of microorganisms?
Briefly describe the 2 step process in the development of atheromatous plaques
Injury to endothelial lining of artery
Chronic inflammation and healing response
Describe some possible causes of endothelial injury
Haemodynamic disturbances (turbulence) Hypercholesterolaemia
How are injured endothelial cells functionally altered?
Enhanced expression of adhesion molecules
High LDL permeability
Increased thromnobogenicity
Increased inflammatory cells
What can be done to prevent atherosclerosis or its progression?
Stop smoking Control blood pressure Weight loss and diet modification Regular exercise Cholesterol lowering drugs Aspirin (inhibits platelet aggregation) Surgery
