The carotid arteries are located on each side of your neck and supply blood to your brain. Carotid artery disease is the term used to describe narrowing of these arteries due to the build-up of atherosclerotic plaque (deposits of fatty and fibrous tissue on the inside of the arteries). Fragments of plaque, or blood clot that forms over the plaque, may break off and be carried by the blood flow into the brain, where they can block arteries, causing a stroke. About 15% of all strokes are due to carotid artery disease. Carotid angioplasty and stenting is a minimally invasive procedure that opens narrowed arteries to prevent a stroke.