ILA 1 - Atherosclerosis

Question 1

Describe structure of the normal arterial vessel wall

Answer 1

Inner: Tunica intima (simple squamous endothelium surrounded by connective tissue basement membrane with elastic fibres)
Tunica media (Fenestrated elastic fibres with smooth muscle and collagen)
Outer: Tunica adventitia (Thin layer of connective tissue with lymphatics, nerve and vasa vasorum)

Question 2

Structure of an atherosclerotic plaque

Answer 2

• Lipid
• Necrotic core
• Connective tissue
• Fibrous cap

Question 3

Describe the pathogenesis of atherosclerosis

Answer 3

• Endothelial cell dysfunction and fatty streak formation
• High LDL pass into tunica intima and become oxidised (cant leave). Activate endothelial cells which present leuikocyte adhesion molecules
• Leukocytes move into intima and attract monocytes (Macrophages/tH cells)
• Macrophages take up oxidised LDL, forming foam cells which secrete IGF-1, causing smooth muscle migration from tunica media to intima. This forms fibrous cap.
• Foam cells die, releasing growth factors and cytokines, growing the plaque.
• Plaque occludes vessel or ruptures, triggering platelet adhesion and clot formation.

Question 4

Which 3 coronary vessels are most likely to be occluded

Answer 4

Left anterior descending
Right coronary
Left circumflex

Question 5

MoA of statins

Answer 5

HMG-Coenzyme A reductase inhibitor. Prevents conversion of HDL to LDL

Question 6

Primary and secondary prevention of atherosclerosis problems

Answer 6

Primary
- Exercise
- Healthy diet
- Stop smoking

Secondary
- Antihypertensives (ACEi, CCB, ARB)
- Statis
- Social prescribing (gym, weight loss)
- BP monitoring.

Question 7

Explain how smoking, diabetes, HTN, high cholesterol and obesity lead to atherosclerosis

Answer 7

Smoking - Free radicals, nicotine, CO damage endothelium
Diabetes - Increased free radicals, loss of NO (which relaxes vessels), promotes platelet aggregation
HTN - Increased pressure = Increased shearing forces
Obesity - High LDL, inflammatory cytokines

Question 8

Define co benefits in health

Answer 8

Positive effects a policy or measure may have on another objective.

E.g. stop driving and walk. Environmental and health good