Carotid artery disease is a type of peripheral arterial disease in which there is “hardening of the arteries” (atherosclerosis) in the main arteries carrying oxygen-rich blood to the brain (the carotid arteries). These arteries are found on either side of the neck, extending from the aorta to the brain. During atherosclerosis, the inside of the artery is gradually narrowed with a buildup of fatty plaque. As this plaque becomes more severe, there is a chance pieces may break off and travel further downstream in the artery.

If the pieces of plaque become stuck in an artery and obstruct the flow of oxygen-rich blood, the person can suffer a stroke (an ischemic stroke). This is caused by a severe lack of oxygen reaching the brain (cerebral ischemia). Ischemic strokes are the most common form of stroke in the United States.