It is an irregular thickening of arterial walls and narrowing of their lumen due to deposition of yellow plaques or atheromas in their tunica intima and inner part of tunica media. Atheromas consist of cholesterol and other lipid materials. They are formed from low-density lipoproteins or LDL. LDL can pass through the endothelium. It gets precipitated inside an artery. Normally blood contains the enzymes paraoxonase which prevents LDL precipitation. However, a diet rich in cholesterol (for example- egg, butter, ghee) overcomes the effect of enzymes and causes the deposition of LDL. It slowly brings about atherosclerosis. Atherosclerosis causes hypertension due to stenosis or narrowing of arteries, arterial occlusion, kidney damage, brain stroke, reduced limb activity, angina and myocardial infarction. The effect can be reduced by controlling hypertension and lowering body lipid levels through diet and medicines.
It is the disease of blood vessels where the arteries become hardened due to deposition of plaque as a result of the precipitation of calcium salts with cholesterol. This calcification of the plaque ultimately makes the wall of the arteries stiff and rigid and prevents its dilation, leading to its rupturing. The blood leaking from the ruptured wall may clot and block the pathway of blood flow. Such a thrombosis of clot formation in the coronary artery may cause heart attack and even death.
Difference Between Atherosclerosis and Arteriosclerosis:
It refers to the deposition of lipids (especially cholesterol) on the wall lining of arteries.
It refers to the hardening of the arteries due to deposition and thickening.
The plaque formation occurs due to the proliferation of the fibres and small muscles around it.
Plaque formation occurs due to the precipitation of calcium salts with cholesterol.
Platelets derived growth factors (PDGF) cause the proliferation of smooth muscles.
Platelets derived growth factors (PDGF) do not play any role in the proliferation/plaque formation.