2.3 Health and disease Flashcards
Coronary heart disease
Coronary heart disease is caused when fatty material is deposited inside the coronary arteries.
Blood flow is reduced and less glucose and oxygen reach the heart for respiration.
This means that less aerobic respiration and more anaerobic respiration takes place so less energy is released.
Less energy is available for the heart to contract so less glucose and oxygen are transported to the working muscles by the blood from the heart.
Less carbon dioxide is removed from the body resulting in breathlessness and tiredness.
If cells are starved of nutrients, they can die and a heart attack can happen.
Factors that can contribute to coronary heart disease include: Genetic factors, Gender, Age, Diet And smoking status.
Heart failure
When the heart fails to pump blood effectively.
Causes: valves leaking, causing backflow and weakness in heart muscles (usually due to old age).
When heart failure occurs, the only effective treatment is a donor heart transplant. An artificial heart can be used in the short term, while the patient is waiting for a heart transplant, or allow the heart to rest to help recovery.
Statins
High cholesterol levels are treated with drugs called statins which stop the liver producing as much cholesterol. Patients can also change their diet to help reduce cholesterol.
Disadvantages - need to be taken regularly and long term otherwise they are not as effective.
Takes time to have an effect.
Side effects include muscle and joint pain and kidney problems.
Stents
Stents are used to treat narrow coronary arteries by widening the lumen to increase blood flow. If the coronary artery is too damaged, bypass surgery is used. A vein is transplanted from the leg to bypass the blockage.
Disadvantages - Risk of blood clots occurring.
Risk of infection during surgery.
Risk of damage to blood vessels during surgery.
Heart valves
Heart valves prevent the backflow of blood.
They can become faulty due to heart attack, infection or old age.
Faulty heart valves can be replaced using biological or mechanical valves.
Risk factors
Risk factors are factors that increase the probability of developing a disease. Often, non-communicable diseases arise due to the interaction of numerous risk factors. Risk factors can be placed into one of two categories:
Lifestyle
Substances - can be in both the individual’s body or the environment.
Risk factors (smoking)
Smoking is a proven risk factors for cardiovascular disease.
Smoking during pregnancy is a proven risk factor for the low birth weight of babies.
Risk factor (diet)
Poor diet is a proven risk factors for cardiovascular disease.
Obesity is a proven risk factor for Type 2 diabetes.
Risk factors (alcohol)
Excessive alcohol intake is a risk factor for liver and brain damage.
Cirrhosis of the liver.
Excessive alcohol consumption during pregnancy is a proven risk factor for brain damage in babies.
Cancer
Cancer is the result of changes in cells that lead to uncontrolled growth and division.
Chemical carcinogens and exposure to ionising radiation (radiation that can damage cells) is a proven risk factor for cancer as well as other genetic factors.
Artificial heart advantages and disadvantages
Advantages - short waiting times
Less chance of patients immune system rejecting it.
Disadvantages - Do not work as well as real hearts.
Increased risk of blood clot, leading to increased risk of stroke.
Malignant and benign tumors
Malignant tumours invade neighbouring tissues and spread to different parts of the body in the blood where they form secondary tumours.
Benign tumours are growths of abnormal cells which are contained in one area, usually within a membrane. They do not invade other parts of the body.
