The disease starts at the relatively young and begins to really show itself in the fifth through seventh decades of life. It mainly affects the larger arteries. The chief vessels involved are the Aorta and its principle branches which seriously affects the heart, brain, kidney, intestine, and legs.
Atherosclerosis has the characteristic of a lesion, or atheromatous plaque.
This is a thickening of the intima due to the deposition of lipid and connective tissue. The atheroma is formed only slowly, gradually protruding into the lumen. As the lumen, or inside of the arteries get smaller, the harder it is for the blood to flow through freely, thus reducing blood flow. In the heart reduced blood flow will mean a steadily declining ability of the heart to meet its pumping demands. Initial thickening can be detected as early as ages 10-20 with further progression producing symptoms as early as age 35.