Stroke prevention and Carotid Artery Disease

The carotid arteries are the main supply of oxygenated blood to our brains. Accumulation of fat and cholesterol over time can causes atherosclerosis and narrowing of those arteries. Plaque build-up within the carotid artery causes a reduction in the blood supply to the brain and the eyes. Small plaque particles can break-off and travel to the brain. This risks causing minor or major strokes. Undiagnosed and poorly managed carotid artery atherosclerosis can cause a severe stroke.

Risk factors

Screen your carotid and vascular status if you have some of these risk factors:

• Old age (>65yrs)
• Gender - more common in males
• Smoker
• Diabetes Mellitus
• High blood pressure
• High cholesterol
• Family history of stroke
• Obesity and sedentary lifestyle

 Symptoms

Most people with carotid artery disease do not experience any symptoms until the artery is critically narrow and they experience a stroke. A minor transient mini-stroke might be the only warning signal for some people:

• Sudden temporary loss of vision in one eye
• Sudden weakness or numbness in an arm or leg (on one side of body)
• Drooping of the face
• Difficulty speaking
• Sudden paralysis of one side of the body

If you think you have experienced any of those symptoms, seek help straight away, even if the symptoms are short-lived.

Diagnosis

Diagnosis is usually made with an ultrasound examination. Other imaging such as a CT or MRI are alternative non-invasive ways of evaluating carotid arteries.

Duplex ultrasound

Uses variable means of technology to assess consistency, narrowing and hemodynamics of the carotid arteries.

CT angiogram

A CT scan involves injecting dye into the veins while the head and neck are imaged using special x-rays taken from multiple angles and used to re-construct a 3D-image. CT also allows the brain and the arteries within the skull to be examined.

MRI

An MRI is similar to a CT scan in that it involves injecting dye into the veins while the head and neck are imaged. Where CT uses radiation, the MRI uses magnetic imaging.

Ultrasound, MRI and CT offer different but complementary information in diagnosing carotid artery disease. Modern used dye (contrast) is very safe to use for most people.

Treatment

The most common treatment for severe carotid disease is carotid surgery, also known as endarterectomy. The surgery can be done under a local or general anaesthetic. It involves making an incision on the side of the neck, opening up the artery and removing the blockage from within the artery, thus improving the blood flow to the brain. Sometimes, a patch is used to repair the artery, ensuring it remains wider than before. While the artery is being repaired, occasionally a tube (shunt) might be used to reroute the blood flow around the segment of artery being operated on.

In cases where surgery is deemed to be too high risk or technically difficult, the other option to open the artery is a carotid stent. This is most commonly performed under local anaesthetic, as an endovascular (keyhole) procedure.