Atherosclerosis

Atherosclerosis


ATHEROSCLEROSIS

  • Atherosclerosis is an thickening & hardening muscular arteries which is characterised by soft gramous lipid cores (atheromatous plaque).
  • It is the commonest & most important arterial disease.
  • Most commonly affected are aorta, coronaries & cerebral arterial system.
  • Most commonly coronoary circulation affected is – Left anterior descending artery

 

Etiology

Pathogenesis-

  • Most widely accepted theory for atherosclerosis is inflammatory response to endothelial injury.
  • According to this hypothesis, atherosclerosis is a chronic inflammatory response of the arterial wall initiated by injury to endothelium.
  • Hyperlipidemia, hypertension, smoking can cause endothelial injury.
  • Foam cells are formed when macrophages & smooth muscle cells accumulated oxidised LDL.
  • Chlamydia Pneumoniae presents the strongest association with human atherosclerosis.

Morphological features-

1. Fatty streaks & Dots- are the earliest lesions composed of intimal collections of foamy macrophages & smooth muscle cells.

  • Prominent in the aorta (often in posterior wall)

2. Gelatinous lesions- develop in the intima of the aorta.

3. Artheromatous plaques (arthemaous lesions/ fibrous plaque)-

  • Most severely affected is the abdominal aorta.
  • Involves iliac, femoral, carotid, coronary & cerebral arteries.
  • Superficial luminal part of the fibrous cap (convex) composed by smooth muscle cells.
  • Cellular area under fibrous cap composed of macrophages, foam cells, lymphocytes.
  • Deeper central soft core consists of cholesterol clefts, fibrin, necrotic debris & lipid- laden foam cells.

4. Complicated plaques-

  • Calcification- occurs more commonly in advanced athermatous plaques.
  • Ulceration
  • Thrombosis- superimposed thrombi
  • Haemorrhage
 

 

Clinical features-

Major clinical effects of atheroscelrosis are-

  1. Heart (coronary artery disease, IMD, MI)
  2. Brain (stroke)
  3. Aorta (aneurysmal dilatation)
  4. Intestine (ischaemia, infarct)
  5. Lower extremities (gangrene)
  • Blood vessels affected by atherosclerosis- abdominal aorta (most commonly), Circle of Willis (least commonly affected)

Exam Important

  • Most commonly affected are aorta, coronaries & cerebral arterial system.
  • Most commonly coronoary circulation affected is – Left anterior descending artery

 

Etiology

Pathogenesis-

  • Most widely accepted theory for atherosclerosis is inflammatory response to endothelial injury.
  • According to this hypothesis, atherosclerosis is a chronic inflammatory response of the arterial wall initiated by injury to endothelium.
  • Hyperlipidemia, hypertension, smoking can cause endothelial injury.
  • Foam cells are formed when macrophages & smooth muscle cells accumulated oxidised LDL.
  • Chlamydia Pneumoniae presents the strongest association with human atherosclerosis.
Morphological features-

1. Fatty streaks & Dots- are the earliest lesions composed of intimal collections of foamy macrophages & smooth muscle cells.

  • Prominent in the aorta (often in posterior wall)

2. Gelatinous lesions- develop in the intima of the aorta.

3. Artheromatous plaques (arthemaous lesions/ fibrous plaque)-

  • Most severely affected is the abdominal aorta.
  • Involves iliac, femoral, carotid, coronary & cerebral arteries.
  • Superficial luminal part of the fibrous cap (convex) composed by smooth muscle cells.
  • Cellular area under fibrous cap composed of macrophages, foam cells, lymphocytes.
  • Deeper central soft core consists of cholesterol clefts, fibrin, necrotic debris & lipid- laden foam cells.

4. Complicated plaques-

  • Calcification- occurs more commonly in advanced athermatous plaques.
  • Ulceration
  • Thrombosis- superimposed thrombi
  • Haemorrhage
  • Blood vessels affected by atherosclerosis- abdominal aorta (most commonly), Circle of Willis (least commonly affected)
 
Don’t Forget to Solve all the previous Year Question asked on Atherosclerosis
Click Here to Start Quiz

Module Below Start Quiz

Leave a Reply

%d bloggers like this:
Malcare WordPress Security