Coronary Heart Disease - non communicable
Cards (12)
- layers of fatty material build up in the coronary arteries, narrowing them
- reduce their blood flow, results in lack of oxygen for the heart
- can result in heart attack
- Atherosclerosis:
- fat and cholesterol is deposited as plaque or atheroma in artery walls
- STENTS
- used to widen narrowed arteries
- some release drugs to prevent blood clots
- BYPASS SURGERY
- use sections of veins from other parts of body to create a graft - alternate route for blood to flow to avoid the narrowed artery
- STENTS ADVANTAGES
- cheap
- less risky surgery, no general anaesthetic
STENTS DISADVANTAGES- can't open blocked or very narrow arteries
- can cause blood clots (so can atheroma)
- tissue can grow over stent, ineffective
- BYPASS SURGERY ADVANTAGES
- effective against completely blocked arteries
BYPASS SURGERY DISADVANTAGES- expensive
- risky surgery - open heart surgery
- Heart problems - leaky valves
- can cause backflow of blood > heart won't pump blood as efficiently so less blood leaves heart
- MECHANICAL VALVES
- titanium or polymers, last a long time
- need medicine for the rest of life to prevent blood clotting around it
- BIOLOGICAL VALVES
- based on valves from animals - pigs/cattle/human donors
- work well, effective
- last 12-15 years
- anti - clotting medicine isn't needed
- Artificial pacemakers
- cells in right atrium control heart beat (natural pacemaker cells)
- electrical device implanted in chest, send strong and regular electrical signals to stimulate it to beat properly
- some can stimulate it to beat faster in exercise
- Artificial blood ADVANTAGES
- no risk of disease
- readily available
- long shelf life
- doesn't always need to be refrigerated
- no religious objections
- can be good at carrying oxygen
- Artificial blood DISADVANTAGES
- broken down quickly in body
- doesn't clot
- doesn't provide food/nutrients
- can't defend against disease
- can cause side effects