BIO - cardiovascular disease

• coronary heart disease is life-threatening
• coronary heart disease is when the coronary arteries that supply the blood to the muscle of the heart get blocked by layers of fatty material building up.
• coronary heart disease causes the arteries to become narrow, so blood flow is restricted and there's a lack of oxygen to the heart - this can cause a heart attack
• stents keep arteries open
• stents are tubes that are inserted inside arteries, they keep them open, making sure blood can pass through to the heart.
• stents are a way of lowering the risk of a heart attack in people with coronary heart disease
• stents are effective for a long time and the recovery time from the surgery is relatively quick
• with stents, there is a risk of complications during the operaation and a risk of infection from surgery
• with stents, there is also a risk of patients developing a blood clot near the stent - this is called thrombosis
• statins reduce cholestrol in the blood
• statins are drugs that reduce the amount of cholestrol produced in the liver which then goes into the bloodstream
• by reducing the amount of cholestrol in the blood, statins can reduce the risk of strokes, coronary heart disease and heart attacks
• statins are a long term drug that must be taken regularly
• statins can sometimes cause negative side effects
• if a patient has a heart failure, doctors may perform a heart transplant using donor organs from people who have recently died
• if donor organs aren't available right away or the are not the best option, doctors may fit an artificial heart
• artificial hearts are mechanical devices that pump blood for a person whose own heart has failed
• they are used as a temporary fix (most of the time), 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 some cases they are used as a permanent fix, which reduces the need for a donor heart
• the main advantage of artificial hearts is that they are less likely to be rejected by the body's immune system than a donor heart - this is because they are made from metals or plastics, so the body doesn't recognise them as foreign and attack the same way as it does with living tissue
• surgery to fit an artificial heart can lead to bleeding and infection
• artificial hearts don't work as healthy/efficiently as natural ones - parts of the heart could wear out or the electric motor could fail.
• blood doesn't flow through artificial hearts as smoothly - which can cause blood clots and lead to strokes
• a patient with a permanent artificial heart has to take drugs to thin their blood and prevent blood clots and strokes
• the valves in the heart can be damaged or weakened by heart attacks, infection or old age
• damage may cause the valve tissue to stiffen, so it won't open properly
• a valve may become leaky, allowing blood to flow in both directions rather than just forward - this means that blood doesn't circulate as effectively as normal
• severe damage can be treated by replacing the valve
• replacement valves can be ones taken from humans or other mammals - these are called biological valves
• valves can also be man-made - mechanical valves
• replacing a valve is a much less drastic procedure than a whole heart transplant, but fitting artificial valves is still a major surgery and there can still be problems with blood clots
• artificial blood can keep you alive in an emergency
• when someone loses a lot of blood, their heart can still pump the remaining RBCs around, as long as the volume of blood can be topped up
• artificial blood is a blood substitute - used to replace the lost volume of blood
• its safe if no air bubbles get into the blood
• artificial blood keeps people alive - this may give the patient enough time to produce new blood cells, if not the patient will need a blood transfusion