Peripheral Artery Disease - Causes - Causes

Atherosclerosis is the main cause of PAD.

Atherosclerosis in the leg arteries
Atherosclerosis in the leg arteries. The image shows how PAD affects the arteries in the legs. Figure A shows a normal artery with normal blood flow. The inset image shows a cross-section of the normal artery. Figure B shows an artery with plaque buildup that is partially blocking blood flow. The inset image shows a cross-section of the narrowed artery.

Plaque buildup in the arteries is called atherosclerosis. Atherosclerosis is a disease in which a waxy substance called plaque builds up on the inner lining of arteries. Plaque is made up of fat, cholesterol, fibrous tissue, and calcium. In PAD, plaque may reduce or fully block the flow of oxygen-rich blood through arteries to the body’s vital organs and the limbs.

This health topic focuses on PAD in the legs and feet, but other types of PAD block blood flow to the brain, kidneys, or the intestines. A person may have atherosclerosis in just a single artery or in many.

Scientists think atherosclerosis may start with damage to the inner wall of the artery. Cholesterol and cell waste traveling in the blood can build up in the damaged area. This video shows how buildup of cholesterol and other waste can lead to plaque buildup (atherosclerosis). The artery narrows as the plaque grows, reducing the flow of oxygen-rich blood to the limbs and organs. Over time, the plaque can break and flow into the bloodstream. This may lead to blood clots, which can block blood flow. If this happens, nearby tissue can't get enough oxygen and may die. Medical Animation Copyright © 2020 Nucleus Medical Media Inc. All rights reserved.