Atherosclerosis. Build up of lipid deposits that eventually can obstruct the arteries. This is more important in the heart, brain, and legs.
In degrees. Atherosclerosis affects the arteries in varying degrees and stages. One of the first manifestations is an attenuation or loss of the normal dilatory response of arteries. They also become progressively stiffer and as they accumulate more and more internal debris the flow becomes more turbulent. Increasing activation of the inflammatory process is noted, with resultant clots and their sequelae.