More on Cardiovascular Disease

• What are mechanical hearts?

  They are mechanical devices which pump blood for people whose hearts have failed
• Are mechanical hearts permanent or temporary?

  Temporary
• What is the advantage mechanical hearts have over donor hearts?

  Mechanical hearts have less of a chance to be rejected by the body
• Why are mechanical hearts more likely to be accepted by the body?

  The immune system doesn't see the plastic and metal as 'foreign' and so doesn't attack it
• Are artificial hearts more or less effective than natural hearts?

  Less effective
• Does blood flow smoother or less smooth in an artificial heart compared to a natural heart?

  Less smooth
• What can happen as a result of an artificial heart?

  • Infection during surgery
  • Blood clots
  • Strokes
• What must people with artificial hearts take to reduce the risk of strokes and blood clots?

  Blood thinners
• What is the risk of using blood thinners?

  Lots of blood can be lost if they are injured
• What can weaken valves in the heart?

  • Infection
  • Heart attacks
  • Old age
• What happens to damaged valves?

  They stiffen and don't open properly or they become leaky allowing blood to flow in both directions
• What can be used to replace heart valves?

  • Biological replacements from other humans or mammals like pigs
  • Artificial mechanical valves
• Can valve replacement surgery still result in blood clots?

  Yes
• When is artificial blood used for a patient?

  When lots of the volume of blood has been lost
• Can the blood still pump enough oxygen around the body after losing lots of blood?

  Yes if the volume is topped up
• How many red blood cells can people lose while remaining able to supply enough oxygen to their body?

  Two thirds