Atherosclerosis From Fatty Streaks to Strokes. In a healthy person, blood flows freely from the heart to all parts of the body through miles of arteries. But disease sometimes damages the arteries, slowing the flow of blood or even stopping it. When that happens, the result can be extremely dangerous, resulting in a stroke or heart attack. Atherosclerosis clogs the blood's pathways with an outgrowth called fibrous plaque, which narrows the arteries, developing gradually over years and even decades.
Fibrous plaque begins as changes in the structure of the artery or fatty streaks.
These streaks, one of the first signs of atherosclerosis, are composed of fat-laden blood cells and other material that build up in the artery wall. As atherosclerosis progresses, the streaks gradually change, becoming larger and more complex, turning into intermediate lesions. These lesions, in turn, evolve into fibrous plaquethe still larger, more complicated, and more dangerous advanced form of atherosclerosis. When a fibrous plaque becomes unstable and breaks or tears, thrombi can form on the surface of the plaque. If these clots are large enough, they can block the artery that has already been narrowed by the fibrous plaque.