circulatory disorders Flashcards
CV disorders contribute to __% of all male deaths in the UK in 2014
28
cost __billion per year with direct health care costs at £__billion
19,
9
vascular or arterial occlusion =
blockage
vascular occlusion results from:
→ thrombus
→ embolism
→ atherosclerosis
→ compression
what do the consequences of occlusions depend on?
→ type of tissue → artery or vein
→ speed at which occlusion occurs
→ availability of collateral circulation (e.g. venous system has more anastomoses (links)
what is a thrombus made up of?
endothelial cells, platelets, coagulation cascade (fibrin)
most common in middle age/elderly people with CV disorders =
arterial thrombus
increased incidence in smokers and diabetics
venous thrombosis occurs in ___ ___ ______ and is the result of ______
any age person, immobility
what makes up the virchows triad (thrombus formation)
1) alteration of blood constituents
2) damage to endothelial lining
3) altered blood flow
formed from venous emboli that passes through the right side of the heart into the pulmonary artery
pulmonary embolism
from arterial system to variety of organs
systemic embolism
disease of the intima
atherosclerosis
disease of the media
arteriosclerosis
atherosclerosis causes:
endothelial damage → leads to narrowing/obstruction of vessels → lead to thrombosis
arteriolosclerosis causes:
increased wall thickness, decreased elasticity, hypertension (high BP)
how does an atheromatous plaque form?
asymptomatic fatty streak → atheromatous lesion → atheromatous plaque
what are the 3 layers of an atheromatous plaque?
fibrous cap → cellular layer → necrotic core
what things make up the fibrous cap of plaque?
→ smooth muscle
→ collagen
→ elastin
→ proteoglycans
what things make up the cellular layer of plaque?
→ macrophages
→ T cells
→ smooth muscle
what things make up the necrotic core of plaque?
→ macrophages taking up macrophage foam
→ cholesterol clefts
→ lipids
→ cellular debris
calcification of plaque often occurs
what are the processes of plaque formation?
1) ENDOTHELIAL ACTIVATION AND DYSFUNCTION
(promotes lipid accumulation)
2) INFLAMMATORY RESPONSE
3) IMMUNE CELL RECRUITMENT
(macrophages ingest lipids → form foam cells)
4) RECRUITMENT AND PROLIFERATION OF SMOOTH MUSCLE & EXTRACELLULAR MATRIX SYNTHESIS
what happens if a plaque has a thinner cap?
more likely to rupture
what are the general consequences of plaque formation?
→ narrowing/obstruction of vessels
→ rupture
→ embolism
→ calcification
what are the specific consequences of plaque formation?
→ myocardial and cerebral infarctions
→ aortic aneurysms
→peripheral vascular disease
