ILA Flashcards
Structure of an atherosclerotic plaque
Lipid, Necrotic core, Connective tissue, Fibrous “cap”
Stimulus for an atherosclerotic plaque
Adhesion- Chemoattractants released from leukocytes
Examples of non-modifiable risk factors for atherosclerosis
Age, gender, race, family history, Type 1 diabetes
Examples of modifiable risk factors for atherosclerosis
smoker, lack of exercise, weight, (borderline) type 2 diabetes, hypertension, high cholesterol
Risk factor for atherosclerosis- smoking
Releases free radicals, nicotine + CO into the body/blood
-These damage endothelial cells
Risk factor for atherosclerosis- hypertension
Increased pressure 🡪 increased damage of the wall
Risk factor for atherosclerosis- diabetes
-High glucose levels in the blood
-Increased Free radicals
-Increased oxidation of LDLs 🡪 means they get stuck
-Loss of nitric oxide (NO)
-Which normally allows relaxation of vessel + increased flow
-Promotes platelet aggregation
Risk factor for atherosclerosis- cholesterol
High LDLs
-Can pass in and out of the arterial wall in excess, accumulates in arterial wall, undergoes oxidation and glycation
Risk factor for atherosclerosis- Obesity
Increases proinflmmatory cytokines
Risk factor for atherosclerosis- Exercise
-Helps rebalance of low- and high-density lipoproteins
-Reduces blood pressure
Pathophysiology of atherosclerosis
- Endothelial cell dysfunction
- High levels of LDL in the blood
- Inflame (activate) endothelial cells (leukocytes)
- Macrophages take up lipid to form foam cells
- Foam cells
- Formation of a fatty streak in intimal layer
- The activated macrophages (release products - cytokines and growth factors)
- Smooth muscle proliferation (to intima) around the lipid core 🡪 formation of a fibrous cap (collagen)
- Plaque either: -Occludes lumen 🡪 angina
-Ruptures
-Result of inflammatory conditions
-When the plaque ruptures
-Platelets adhere and clotting process begins
Role of macrophages in atherosclerosis
take up lipid (oxidised LDLs) to form foam cells (inflammatory response)
Main 3 coronary arteries to be occluded
-LAD (left anterior descending)
-Right coronary A
-Left circumflex
Role of foam cell in atherosclerosis
-Promote migration of SMCs from tunica media 🡪 tunica intima
-When foam cells die 🡪 Lipid content released 🡪 plaque growth
Secondary preventative measures- atherosclerosis
Statin, antihypertensive, diabetes control (meds, carbs intake), social prescribing
Primary preventative measures-atherosclerosis
Exercise more, eat more healthily, stop smoking