Circulation

• Artificial hearts are occasionally used to keep patients alive whilst waiting for a heart transplant, or to allow the heart to rest as an aid to recovery
• Artificial pacemakers are electrical devices used to correct irregularities in the heart rate
• PROS OF ARTIFICIAL HEART

  Easily available

  Less chance of patient's immune system rejecting it
• CONS OF ARTIFICIAL HEART

  Expensive

  Patients need blood thinners for their whole life to avoid blood clotting
• 2 WAYS OF VALVE MALFUNCTION

  • Valve is not closing properly resulting in a leakage and backflow of blood
  • Valve is too stiff to open properly resulting in restricted blood flow
• BIOLOGICAL VALVES

  • Animals (pigs or cattle) or human donors
  • Very reliable
  • No medication
  • 12 to 15 years
• MECHANICAL VALVE

  • Made from titanium
  • 20 years
  • Blood thinners/medication for the rest of the life to stop clotting
  • Risk of infection
• In coronary heart disease, layers of fatty material build up inside the coronary arteries and narrow them. This reduces the blood flow through the coronary arteries, resulting in a lack of oxygen for the heart muscle
• Stent is inserted into an artery to keep it open to allow blood flow to the heart
• Statins are drugs that destroy cholesterol by reducing production (liver) and absorption (intestine) of cholesterol
• PROS OF STENTS

  • Quick recovery time
  • Long lasting
  • Lowers risk of an heart attack
• CONS OF STENTS

  • Risk of infection
  • Surgery complications
  • Rejection to anaesthesia
  • Risk of blood clot near stent
• PROS OF STATINS

  • Reduces the risk of strokes, CHD, heart attacks
  • Increases good HDL
  • May prevent other diseases
• CONS OF STATINS

  • Needs to be taken on a regular basis
  • Side effects like headaches or kidney failure
  • Takes time to work
• Antigens are proteins on the surface of cells
• PREVENT REJECTION OF TRANSPLANT ORGAN

  • A donor organ with a ‘tissue-type’ similar to that of the recipient is used
  • The recipient is treated with drugs that suppress their immune system