Carotid artery disease is also known as carotid artery stenosis. This refers to the narrowing of the carotid arteries. This narrowing is majorly caused by the accumulation of fatty substances and cholesterol deposits known as plaque. Carotid artery occlusion refers to the complete or partial impeding of the artery. When carotid arteries are blocked, there is an increased risk of having stroke.
Carotid arteries are two big blood vessels that send oxygenated blood to the large front of the brain. It is this part of the brain that is responsible for speech, personality, thinking and sensory and motor functions. In most cases, the pulse can be felt in the carotid arteries on both side of the neck, right beneath the angle of the jaw line.
Strokes are sometimes called brain attack (they are similar to heart attack).  It occurs when blood flow is cut off from a part of the brain. If the lack of blood persists for more than three to six hours, the damage is usually permanent. In most cases, stroke occur if:
- The artery becomes extremely narrowed
- There is a rupture in an artery to the brain that has atherosclerosis
- A blood clot forms and obstructs a blood vessel
- A piece of plaque breaks off and moves to the smaller arteries of the brain.
Strokes can happen as a result of other conditions asides carotid artery disease. For example, sudden bleeding in the brain, known as intracerebral hemorrhage, can lead to stroke. Other possible causes include:
- Atrial fibrillation
- High blood pressure
- Cardiomyopathy 
- Blockage of small arteries inside the brain
- Sudden bleeding in the spinal fluid space – subarachnoid hemorrhage
Symptoms Of Carotid Artery Disease
In some cases, no symptoms manifest. Plaques builds up in the carotid artery over time with no warning symptoms until there is a transient ischemic attack (TIA) or a stroke.
Symptoms of stroke are:
- Sudden serious headache
- Problems with memory
- Difficulty swallowing (known as dysphagia) 
- Sudden dizziness or confusion
- Sudden difficulty in walking, loss of balance and lack of coordination
- Weakness, tingling or numbness on one side of the face, one side of the body or in one arm or leg
- Sudden loss of vision, blurred vision or difficulty in seeing out of one or both eyes
- Trouble speaking (known as aphasia)