1 - Cardiovascular Intro Flashcards
What are the functions of the cardiovascular system?
- supply organs with O2, glucose, nutrients, hormonal messages etc.
- remove waste products
- homeostasis
- stop bleeding, repair damage
- initial immune reaction
What are the risk factors for heart disease?
- dyslipidaemia
- smoking
- diabetes
- hypertension
- male sex
- increasing age
- family history
(also obesity, sedentary lifestyle, inflammatory disease, S. Asian ethnicity, lower socioeconomic status, lower birth weight)
What are the layers of the artery called?
endothelium and internal elastic lamina = intima layer
media layer and external elastic lamina makes up adventitia layer
What is the first step in the process of atherosclerosis?
Endothelial damage
- expression of inflammatory molecules
- release of inflammatory cytokines
- increased permeability to inflammatory cells, lipids
What happens once an immune reaction is initiated in the process of atherosclerosis?
- monocytes differentiate into macrophages
- T-lymphocyte action
- accumulate lipids (foam cells)
- fatty streak can be seen macroscopically
What are the steps leading up to complex plaque formation?
- foam cells undergo apoptosis
- lipid pools in the subendothelial space
- plaque development
- fibrous collagen cap formation
- plaque becomes complex
What are the characteristics of a complex plaque?
- lipid, cholesterol
- cells + cell debris (macrophages, T-cells, smooth muscle cells)
- collagen, elastin, MPS
- haemorrhage (neovessels)
- calcification
- highly thrombogenic
What happens during atherothrombosis?
- plaque rupture
- thrombogenic core exposed to blood
- clotting cascade activated
- platelets recruited
- thrombus forms
- vessel occlusion (ischaemia, infarction)
What is ischaemia?
reduction of blood flow (reversible)
What is infarction?
lack of blood flow that causes death of cells further down (irreversible)
What is embolisation?
- An embolus is a clot that forms somewhere and travels someplace else.
- distal vessel occlusion
- arrhythmogenic potential
What happens if atherosclerosis occurs in the arteries of the brain?
- stroke
- TIA
- carotid disease
What happens if atherosclerosis occurs in the arteries of the heart?
- heart failure
- arrythmia
- angina
- MI
What happens if atherosclerosis occurs in the arteries leading to the kidney?
renal failure
What happens if atherosclerosis occurs in the arteries leading to the testicles?
impotence
