Atherosclerosis is the build-up of fatty material (such as cholesterol), fibrous material and calcium). The build-up forms an atheroma (degeneration of the walls of the arteries) under the endothelium (cells that line the interior surface of blood vessels).

A: normal artery with good blood flow. B: narrow artery with abnormal blood flow, blocked by a think layer of plaque.Cross-section showing how plaque causes abnormal blood flow in affected arteries

As the atheroma continues to build up it causes a number of things to happen:

  • the artery loses its elasticity
  • the blockage restricts blood flow due to the decreased diameter of the lumen
  • the restricted blood flow increases blood pressure

Atherosclerosis can lead to various cardiovascular diseases such as angina, heart attack, stroke, and peripheral vascular disease (PVD).