Question

Explain the pathophysiology of atherosclerosis with 500 words.

Answer 1

Atherosclerosis

Atherosclerosis is a slow, progressive pathologic condition in which accumulation of fats, cholesterol and other substances like thrombus( blood clot)in and on the arterial wall resulting in obstruction of blood flow.

Specifically it is a chronic inflammatory disease in which the accumulation of lipid laden ladm cells in the intimal layer of the artery.

Causes

• Elevated cholesterol
• Smoking
• High blood pressure
• Obesity

Pathophysiology

Mainly hypercholesterolemia is the reason for atherosclerosis. This makes changes in the endothelial permeability resulting in migration of lipids ( LDL cholesterol) into the artery.

Atherosclerosis occurs by

• Increased cholesterol level cause endothelial dysfunction.
• Formation of lipid layer or fatty streak within the intima
• Migration of leukocytes ( especially monocytes) into the vessel wall
• Foam cell formation
• Degradation of extracellular matrix

Circulating monocyes adhere to the endothelial cells and activates adhesion molecules like selectins and vascular adhesion molecule -1 (VCAM-1). It allows migration of lipds via diapedesis( passage of blood cells through the intact walls of the capillaries, especially during inflammation) in the subendothelial space.

This results in the accumulation of lipids on the arterial wall. Eventually it causes obstruction of blood flow to the area where the artery suppies.