Coronary heart disease: a noncommunicable disease Flashcards
(33 cards)
What happens in coronary heart disease?
-layers of fatty material build up inside the coronary arteries, narrowing them
-this reduces the flow of blood through the coronary arteries, resulting in a lack of oxygen for the heart muscle
-this means that aerobic respiration can’t take place and so no energy is released for muscle contraction so the tissues die
-this may result in a heart attack
What does cholesterol do?
-a chemical that sticks to the walls of blood vessels
-cholesterol develops to form fatty deposits called atheroma
Consequences of coronary heart disease (consequences of cholesterol sticking to the lining of a coronary artery):
-reduces flow of blood through the coronary arteries, resulting in lack of oxygen for heart muscle which means aerobic respiration cannot take place so no energy is released for muscle contraction
-can also result in a blood clot/embolism/thrombus
What are the two main effects that the narrowing of the coronary artery could cause?
-angina
-cardiac arrest
Angina:
-when the blood flow to the heart is reduced
-which means there is a lack of oxygen which means they can’t do as much aerobic respiration
-and don’t release as much energy so stops heart muscles from contracting as easily causing chest pain
Cardiac arrest:
-when the coronary artery is completely blocked so the muscle tissue in the heart gets no oxygen
-and can’t do aerobic respiration and so can’t release any energy
-meaning the muscles can’t contract and the tissue dies so the heart stops
Risk factors for coronary heart disease:
-smoking
-age
-diet - inappropriate diet with high levels of cholesterol e.g. eating lots of red meats and
-saturated fats
-genetics - family history of high cholesterol
-gender - more likely to get CHD if you’re male
-exercise
-obesity
-stress
What should you do to reduce your risk of heart diseases?
-don’t smoke
-exercise frequently
-eat a diet low in fat and don’t excessively eat red meats
Advantages of a heart transplant:
-in case of a heart failure a donor heart, or heart and lungs can be transplanted saving the patients life
-patients live longer
-have a better quality of life
-higher energy levels
Disadvantages of a heart transplant:
-major surgery (risks e.g. bleeding)
-anti-rejection drugs are needed (leading to greater risk of infection e.g. sepsis)
-shortage of donors = long wait for heart transplant
-need time to heal, recover and build up strength
-heart may not work well enough risk of dying afterwards
Advantages of an artificial heart:
-no rejection by body’s immune system
-used to keep patients alive while waiting for heart transplant
-can be used to help allow patient’s heart to rest as an aid to recover
-no wait for donor
Disadvantages of an artificial heart:
-can only be used short term while patient is waiting for a heart transplant
-inefficient and inconsistent as you have to carry around a backpack
-electrical motor could fail
-blood doesn’t flow through artificial hearts as smoothly causing blood clots leading to strokes
-patient has to take blood thinners and if they’re injured blood may bleed out at a very fast pace, if they stop taking blood thinners their blood may clot
-can cause bleeding, infection, organ failure
-must remain permanently linked to a power supply via tubes through the skin - potential source of infection
What are mechanical heart valves?
-An artificial heart valve is a one-way valve implanted into a person’s heart to replace a heart valve that is not functioning properly - it is made from carbon and metal
What are heart valves used to treat?
-in some people heart valves might become faulty
-the heart valve tissue might stiffen preventing the valve from opening fully
-the heart valve might develop a leak if it doesn’t close properly which could cause back-flow of blood - aortic regurgitation
-aortic stenosis - narrowing of the heart valves
How are heart valves inserted?
-Catheter (thin, flexible tube) with a balloon on the tip inserted into an artery in your arm or groin
-Guided to the affected valve
-The balloon is inflated, which expands the opening of the heart valve.
-Balloon is then deflated and the balloon and catheter are removed leaving inserted valve in place
Advantages of mechanical heart valves:
Durability:
Mechanical valves are designed to be very durable and are less likely to require replacement compared to tissue valves. This makes them a preferred option for younger individuals.
Longevity:
A mechanical valve can often last for the rest of a patient’s life.
Reduced Risk of Reoperation:
Due to their durability, mechanical valves reduce the risk of needing future surgeries to replace the valve.
Disadvantages of mechanical heart valves:
-Patients need to take lifelong blood-thinning medication (anticoagulants).
-There’s a higher risk of blood clots forming on the valve.
-Can sometimes make a clicking noise that some people find annoying.
What are biological heart valves?
-Made from animal tissue (like pig or cow) or donor human tissue.
-They don’t last as long as mechanical valves (about 10–20 years).
-Patients don’t need lifelong blood thinners.
-Often used in older patients or those who can’t take anticoagulants.
Advantages of biological heart valves:
-Patients don’t need lifelong anticoagulant medication.
-Lower risk of blood clots compared to mechanical valves.
-Usually quieter—no clicking sound.
Disadvantages of biological heart valves:
-They wear out faster (10–20 years), so may need replacement.
-Slight risk of infection or immune reaction.
-Usually not as durable as mechanical valves.
What are stents?
-Small mesh tubes inserted into narrow or blocked arteries.
-They help keep arteries open, improving blood flow.
-Commonly used to treat coronary heart disease.
-Often inserted with a procedure called angioplasty.
What do stents treat?
-Stents treat coronary heart disease by opening up narrow or blocked arteries.
-They help restore blood flow to the heart.
-Can also be used in other arteries (e.g., legs) to improve circulation.
How is the stent inserted?
Inserted with a procedure called angioplasty.
A small balloon is inflated to open the artery.
The stent (mesh tube) is then placed in the artery to keep it open.
The balloon is removed, and the stent stays in place to keep blood flowing.
Advantages of stents:
-Quick recovery time after the procedure.
-Reduces symptoms like chest pain (angina).
-Keeps arteries open, improving blood flow.
-Can be life-saving in emergencies (like during a heart attack).
