How is atherosclerosis related to heart attacks and strokes?

Atherosclerosis is the hardening and narrowing of the arteries. It is caused by the slow buildup of plaque on the inside of walls of the arteries. Arteries are blood vessels that carry oxygen-rich blood from the heart to other parts of the body.

Plaque is made up of fat, cholesterol, calcium, and other substances found in the blood. As it grows, the buildup of plaque narrows the inside of the artery and, in time, may restrict blood flow. There are two types of plaque:

Hard and stable
Soft and unstable
Hard plaque causes artery walls to thicken and harden. Soft plaque is more likely to break apart from the walls and enter the bloodstream. This can cause a blood clot that can partially or totally block the flow of blood in the artery. When this happens, the organ supplied by the blocked artery starves for blood and oxygen. The organ's cells may either die or suffer severe damage

Atherosclerosis is a hardening of the arteries. Gradually over time, the arteries in the heart and brain (which carries oxygen to these organs) harden and become narrowed with plaque. As the narrowing progresses, less and less oxygen rich blood can get to the heart and brain, increasing your risk for heart attack or stroke.