Atheromatous Vascular Disease Flashcards
Define arteriosclerosis, atheroma and atherosclerosis?
Arteriosclerosis is the thickening and hardening of blood vessels. Causes a reduction in lumen size and a loss of elasticity. In small vessels hypertension is the most common cause.
Atheroma: is the accumulation of intracellular nad extracellular lipid in the tunica initima of medium and large aa. Also effects the tunica media.
Atherosclerosis: is the thickening and hardening of aa due to the formation of an atheroma.
Describe the pathology of atherosclerosis?
- Lipids enter intima through endothelial damage.
- Lipids are phagocytosis by macrophages in the intima to make raised ‘fatty streaks’.
- Some lipids are released by the macrophages forming a ‘lipid plaque’.
Macrophages secrete cytokines which stimulate myofibroblasts to secrete collagen. Damage to the elastic lamina and media occur. - Collagen covers the plaque surface forming a ‘fibrolipid plaque’
Media wall thins with muscle being replaced by collagen, - Lipid in the intima becomes calcified. Surface of plaque ulcerates. Thinning of the media leads to vessel weakness and inelasticity.
What are complications of atheromatous disease?
CVD: MI, Stroke, Peripheral Arterial Disease, Carotid aa stenosis, Renal Stenosis, Aortic Stenosis, Aneurysm.
What are the common sites of atheroma and what are the consequences?
Abdominal Aorta: Development of aneurysm. Carotid aa: Embolic Stroke Coronary aa: Angina, ACS Cerebral aa: Stroke Leg aa: PAD Common iliac >Internal iliac (gluteal region) >External iliac > femoral aa > popliteal aa Popliteal > ant/post tibial aa
Discuss the risk factors for atherosclerosis and methods to modify the risk.
Lifestyle: Smoking cessation Obesity (eat a healthy balanced diet and reduce fat intake) Regular exercise Avoid excessive alcohol intake
Treat contributing conditions:
Hypertension: ACE inhibitor +/- Ca channel blocker +/- diuretic
Hyperlipidaemia: Statin
Previous cardiac event: Anti platelet drugs e.g clopidogrel or asprin
Diabetes: Good control
What is the difference between primary and secondary hyperlipidaemia?
1y = Genetic predisposition e.g. familial hypercholestrolaemia 2y = systemic metabolic disturbance e.g obesity, DM, alcohol