Atherosclerosis

• What is atherosclerosis?

  Atherosclerosis is the pathogenesis of the ischaemia disease.

  Athero - gruel or paste

  Sclerosis - Hardening
• Endothelium?

  Endothelium one cell thickness of epithelial cells that cover all heart and blood vessels. It’s also active it helps the vessel to dilate when it needs to dilate and it helps constrict when it needs to constrict.

  It is antithrombotic - It is non stick. It is a surface that blood should be able to flow freely over.

  one of it‘s major secretion is nitric oxide.
• What ED RF?

  Endothelial Derived Relaxation Factor allows the vessel to dilate and secrete things.

  It’s a semi permeable membrane.
• What happens when the endothelium is damaged?

  It will stop being anti-thrombotic, it will stop being able to vasodilate. It starts restricting its ability to function.
• Injury, migration of inflammatory cell, lipid accumulation and plaque structure

  • Damage can be physical force, chemical irritant
  • Hypertension will be a mechanical force
  • Smoking, toxins, bacteria, viruses can cause damage to the endothelial lining of peoples arteries
• Injury response

  1. Autonomic response in terms of repairing and fixing

  2. Body's defence mechanism kicks in and monocytes will appear to try invade and repair that area
• Increased levels of lipids, sugars or both

  Problem
• Lipid interaction with subendothelium area

  1. Lipids become oxidised

  2. Seen as foreign

  3. Attacked by white blood cells who will appear and try to destroy them
• Parts of the body atherosclerosis can affect?

  Renal system (arteries) - That will reduce the perfusion of the kidney, which will affect renal function. Then there will be problems associated with blood pressure circulating electrolytes.

  Plaque in carotid arteries - It could go up the brain and the patient could end up having a stroke as a result of atherosclerosis in those vessels. Can cause embolic stroke

  • Peripheral artery disease
  • Limb claudication - narrowing of vessel by fibrous plaque
  • Limb ischaemia
• What is AAA?

  Abdominal aortic aneurysm

  Aortic aneurysm - If it ruptures you can die
• How does aortic aneurysm affect the heart?

  Plaque causing a pressure gradient across that vessel because we have an obstruction, less perfusion pressure. Circulating or perfusing that area of heart muscle.
• Risk factors of atherosclerosis?

  Smoking, Obesity, exercise, hypertension, gender, age, high cholesterol, family (genetics).

  Smoking makes blood thicker. It makes the body say I’m carrying less oxygen. So it produces more red blood cells and it’ll carry more oxygen, but more red blood cells (more viscous blood)