The carotid arteries, which are found in the neck, transfer blood from the heart to the brain. When they are affected by atherosclerosis, stenosis (shrinking of the arteries) may occur, leading to the risk of small fragments detaching and make their way to the brain, which can cause a stroke. The risk of neurological complications increases with the severity of the stenosis. The main risk factors associated with atherosclerosis include hypertension, diabetes, high cholesterol and tobacco use.

It is important to note that a stroke can also be caused by carotid occlusion (thrombosis), depending on the quality of blood flow through other arteries.