cardiovascular disease

• cononary heart disease is...


  life threatening
• what is conorary heart disease?


  when the conorary arteries that supply the blood to the muscle of the heart get blocked by the layers of fatty material building up
• what does conorary heart disease cause?

  this causes the arteries to become narrow, so blood flow is restricted and there's a lack of oxygen to the heart muscle - this can result in a heart attack
• coronary heart disease is a type of ... disease


  cardiovascular
• cardiovascular heart disease


  a collective term for various diseases of the heart and blood vessels
• what are stents?


  tubes that are inserted into arteries to keep them open, making sure blood can pass through - this keeps the person's heart beating (and the person alive)
• stent diagram

  
• what do stents lower the risk of?

  a heart attack in people with coronary heart disease
• pros of stents


  - effective for a long time

  - recovery is quick
• cons of stents


  - risk of complications during operation (e.g. heart attack)

  - risk of infection from surgery

  - risk of developing a blood clot near the stent (this is called thrombosis)
• thrombosis


  abnormal condition of a blood clot
• what are statins?


  they are drugs which lower the amount of 'bad' cholesterol in blood.
• what is cholesterol?


  an essential lipid that your body produces and needs to function properly
• what is HDL cholesterol?

  - high density lipoprotein

  - "good cholesterol"

  - smaller molecules

  - removes LDL from the blood and take it to the liver for removal

  - levels should be over 60 mg/dL
• what does HDL do?

  removed LDL from the blood and transports it from tissues to liver
• what is LDL cholesterol?

  - low density lipoprotein

  - "bad cholesterol"

  - large molecules

  - builds up in arteries causing blood clots

  - levels should be around 100-129 mg/dL
• what is LDL do?

  carries cholesterol to various tissues but builds up in arteries causing blood clots
• pros of statins


  - reduces risk of stroke/ heart attack

  - increases amount of HDL cholesterol

  - possibly prevents other diseases
• cons of statins


  - must be taken routinely over a long period of time

  - can cause negative side effects (e.g. kidney failure, memory loss)

  - effect isn't instant
• what do artificial hearts do?

  pumps blood around the body
• why may a patient need to have a heart transplant?

  because of heart failure
• what other option is available if heart donor organs are not available?

  doctors may use an artificial heart
• what are artificial hearts?

  mechanical devices that pump blood for a person whose own heart has failed
• are artificial hearts a temporary or a permanent fix?

  both

  - they're usually only used as a temporary fix, to keep a person alive until a donor heart can be found or to help a person recover by allowing the heart to rest and heal

  - in come cases though they're used as a permanent fix, which reduces the need for a donor heart
• pros of artificial hearts

  - allows the heart to rest/heal

  - readily available

  - less likely to be rejected by the body's immune system
• why is an artificial heart less likely to be rejected by the body's immune system than a donor heart?

  because they're made from metals or plastics, so the body doesn't recognise them as 'foreign' and attack in the same way as it does with living tissue
• cons of artificial heart

  - the surgery can lead to bleeding and infections

  - doesn't work as well as natural heart

  - parts of the heart could wear out or fail

  - the blood doesn't flow as smoothly through properly causing blood clots and strokes
• how does a patient prevent blood clots and strokes with an artificial heart?


  by taking regular drugs to thin their blood, however this can cause problems with bleeding if they're hurt in an accident
• what can be done with faulty valves?

  they can be replaced
• how can the valves in the heart be damaged/weakened?

  heart attacks, infection and/or old age
• what does damage to the valves result in?

  - stiffened valve tissue, preventing it from opening properly

  - leaking valves, allowing blood to flow in both directions rather than just forward
• severe valve damage can be treated by...

  replacing the valve
• where can replacement valves be found?

  - humans or other mammals (biological valves)

  - they can be man-made (mechanical valves)
• pros of valve replacement

  - less surgical trauma

  - decreased blood loss

  - faster mobility

  - less mechanical ventilation

  - improved cosmetic appearance
• cons of valve replacement

  - major surgery

  - there may be blood clot problems
• what does artificial blood do?

  keeps a patient alive by replacing blood
• what happens when a patient loses a lot of blood?

  their heart can still pump the remaining red blood cells around (to get oxygen to their organs), as long as the volume of their blood can be topped up
• what is artificial blood?

  artificial blood is a blood substitute, e.g. a salt solution (saline), which is used to replace the lost volume of blood
• artificial blood advantages


  - safe (if no air bubbles get into the blood), keeping the patient alive

  - may give the patient enough time to produce new blood cells (if not, the patient will need a blood transfusion)
• what would be ideal for artificial blood?

  if it could replace the function of red blood cells (carries oxygen around the body), so that there's no need for a blood transfusion - scientists are currently working on products that can do this