Cerebrovascular accident (CVA) prevention: In many cases, a person may have a transient ischemic attack (TIA), a neurological event with the symptoms of a stroke, but the symptoms go away within a short period of time, usually a few minutes to a few hours. This is often caused by the narrowing or ulceration of the carotid arteries (the major arteries in the neck that supply blood to the brain). If not treated, there is a high risk of having a major stroke in the future. If you suspect a TIA, you should seek medical attention right away. An operation to clean out the carotid artery and restore normal blood flow through the artery (a carotid endarterectomy) markedly reduces the incidence of a subsequent stroke. In other cases, when a person has a narrowed carotid artery, but no symptoms, the risk of having a stroke can be reduced with medications such as aspirin and platelet-inhibiting blood thinners. These medications act by partially blocking the function of blood elements, called platelets, which assist blood clotting.