Cardiovascular disease

• What is cardiovascular disease?

  disease of the heart and blood vessels
• What do cardiovascular diseases include?

  aneurysms, myocardial infarction, thrombosis
• What do most cardiovascular diseases start with?

  atheroma formation
• What is Coronary Heart Disease?

  -type of cvd

  -occurs when coronary arteries have a lot of atheroma in them

  -restricts blood flow to heart muscle

  -leads to myocardial infarction (heart attack)
• What happens when damage happens to the endothelium of an artery?

  -sometimes happens due to high blood pressure

  -white blood cells like macrophages and lipids from the blood clump together under the lining to form fatty streaks
• What is an atheroma?

  -a fibrous plaque formed by many white blood cells, lipids and connective tissue to build up and harden under the lining

  -plaque partially blocks the artery lumen restricting blood flow causing bp to increase
• What is an aneurysm?

  a balloon like swelling of the artery
• How do aneurysms form?

  -starts with the formation of atheroma, these plaques damage and weaken the artery

  -they also narrow the artery increasing bp

  -when blood travels at high bp through a weakened artery, pushes against the layers of the artery through outer elastic layer to form an aneurysm

  -this might burst causing a haemorrhage (bleeding)
• What is thrombosis?

  -formation of a blood clot
• How does thrombosis occur?

  -first the formation of atheromas

  -plaque rupture the endothelium of the artery

  -damage to artery leaves a rough surface

  -platelets and fibrin (protein) accumulate at the site of damage and form a blood clot (thrombus)

  -this cause blockage of the artery or become dislodged and block a blood vessel elsewhere in the body

  -debris from rupture can cause another blood clot to form further down the artery
• How does someone get myocardial infarction?

  -coronary artery become blocked, causing an area of of the heart muscle to be cut off form blood supply and so no oxygen
• What can a heart attack cause?

  Damage and death of the heart muscle
• What are the symptoms of a heart attack?

  -pain in chest and upper body

  -shortness of breath

  -sweating
• When does heart failure occur?

  when large areas of heart muscle are receiving no oxygen
• What are some risk factors of cvd?

  -smoking

  -too much salt in diet
• Risk factors for cardiovascular disease - High blood cholesterol and poor diet

  1. If blood cholesterol is high (above 240mg/100cm3) then risk of CD is increased
  2. This is because cholesterol is one of the main constituents of the fatty deposits that form atheromas
  3. Atheromas can lead to increased blood pressure and blood clots
  4. This could block flow to blood to coronary arteries - causing myocardial infarction
  5. A diet high in saturated fat is associated with high blood cholesterol levels
  6. A diet high in salt also increases risk of CD because it increases risk of high blood pressure
• Risk factors for cardiovascular disease - Cigarette smoking

  1. Both nicotine + carbon monoxide increase risk of CD
  2. Nicotine increases risk of high bp
  3. Carbon monoxide combines with haemoglobin in the blood + reduces the amount of O2 transported in the blood, and so reduces the amount of O2 available to tissues. If heart muscle doesn't receive enough O2 --> heart attack
  4. Smoking also decreases amount of antioxidants in the blood --> important for protecting cells from damage. Fewer antioxidants means cell damage in coronary artery walls is more likely, this can lead to atheroma formation.
• Risk factors for cardiovascular disease - high blood pressure

  1. High blood pressure increases risk of damage to artery walls
  2. Damage walls have an increased risk of atheroma formation, causing further increase in blood pressure
  3. Atheromas can also cause blood clots to form
  4. A blood clot could block flow of blood to heart muscle, causing a myocardial infarction
  5. Anything that increases blood pressure also increases risk of cardiovascular disease e.g. obesity, not exercising and excessive alcohol consumption and smoking