Disease of the carotid artery is related to, in large part, the amount of atherosclerosis (or plaque) that is present in one of the main arteries to the brain—the Internal Carotid Artery (ICA. )Typically, the more plaque that is present, the narrower the diameter of the internal portion of the artery is that is delivering blood to the brain. One potential cause of stroke is the lack of enough blood flow to the brain that may be reduced as the inner diameter of the ICA get smaller. Alternatively, a piece of the plaque in the ICA could break away and travel to the brain lodging in a small artery producing a stroke by restricting blood flow (and oxygen) to a particular area of the brain.
While degree of narrowing within the carotid artery is a factor in determining whether intervention is required, the presence of symptoms related specifically to the carotid artery in question is another important factor to be considered. People may have a significant degree of narrowing of their ICA—in fact, it may even be completely blocked (occluded)—and yet have no symptoms. Others may have moderate degree of narrowing (60%) and exhibit symptoms of a full stroke or a “mini-stroke” (referred to as a Transient Ischemic Attack [TIA].) Utilizing these two factors—in addition to the overall condition of the individual—your physician can make a recommendation that is right for you.