Carotid Artery Disease and Stroke

Carotid arteries supply the brain with oxygenated blood. These arteries extend from the aorta (the main blood vessel) in the chest to the brain inside the skull. As one ages, in combination with various cardiovascular risk factors, these vessels can narrow and harden due to cholesterol build up (called plaque), a process known as atherosclerosis. As the disease progresses, significant plaque builds up, compromising the lumen of the carotid artery and causing a critical reduction of blood flow to the brain. This is known as Carotid Artery Stenosis (CAS) and is a serious health problem since it can cause a stroke.

Plaques and CAS can cause strokes in two ways. The plaque itself can block the artery enough to slow or stop blood and oxygen flow to the brain and cause a stroke. More often though, a piece of the plaque itself, or a clot, breaks off from the plaque deposit and lodges in a branch supplying the brain and cause a stroke.

Certain lifestyle changes may help prevent or at least slow down the process of atherosclerosis and reduce your risk for heart attack, stroke, peripheral arterial disease (PAD) and kidney disease. Risk factors include smoking, high cholesterol, high blood pressure, physical inactivity and obesity.

Stroke Facts

• Every year 700,000 Americans suffer from stroke. There is a stroke every 45 seconds
• Stroke is the No. 3 killer, behind diseases of the heart and cancer
• More women die of a stroke then men. Of every 5 people who die from a stroke, 2 are men and 3 are women
• Stroke death rate per 100,000 population was higher in blacks then in whites
• Americans will pay about $58 billion in 2006 for stroke related medical costs and disability

Symptoms of CAS

Carotid artery stenosis is asymptomatic in its early stages and the first sign of CAS could be a fatal stroke; however, you may experience certain warning signs known as Transient Ischemic Attacks or TIAs. Symptoms of a TIA usually last for a few minutes to 1 hour and include:

• Feeling weakness, numbness, or a tingling sensation on one side of your body, for example, in an arm or a leg
• Losing vision in one eye (many people describe this sensation as a window shade coming down)
• Being unable to speak clearly

TIAs will last from a few minutes to a few hours and the only way to differentiate it from a stroke is its resolution after a few minutes. However, these symptoms indicate that you are at serious risk and under no circumstance should you ignore them. All such symptoms should be reported immediately. Stroke is a medical emergency. Every second counts. Prompt recognition and treatment will allow you to benefit from the stroke chain of survival

Diagnosis

In symptomatic patients the diagnosis is suspected based on history and a physical examination. Confirmation in symptomatic patients as well as for diagnosis in an asymptomatic patient, the physician will often order a carotid artery ultrasound, a non-invasive way of looking at the carotid arteries. This test can show how open your carotid arteries are and how quickly blood flows through them. If this test is normal, often no other tests are required. If the ultrasound does not provide enough information, additional information can be obtained with other non-invasive tests such as CT (CTscan) with dye, or a MRI with dye. A more invasive way of looking at the carotid arteries and the arteries of the brain can be performed by angiography. In angiography, a small nick (2mm) is made in the leg. Under X-ray guidance, we thread a small catheter (<2mm diameter) into the carotid artery and inject a dye that maps out the carotid arteries as well as the arteries supplying the brain, demonstrating the exact location as well as the degree of narrowing in the carotid artery.Tests such as angiography, even though minimally invasive, do carry a small risk of stroke from the procedure itself and hence is usually reserved when an intervention is planned as discussed below.

Treatment

Treatment options are based on the degree of narrowing of the carotid artery, presence or absence of symptoms and overall health.

Lifestyle changes and medications play a cornerstone in the treatment plan. All patients with any form of cardiovascular disease, including carotid artery disease should quit smoking, talk to their doctor about lowering their cholesterol, make every attempt to control their blood pressure and diabetes (under their doctor's supervision) and exercise daily.

In patients with severe disease or the presence of symptoms, more aggressive management may be warranted. There are two ways to treat CAS. The traditional way of treating CAS involves surgery and is known as Carotid Endarterectomy or CEA. The surgeon makes an incision in your neck, and shaves of the plaque from the inside of the carotid artery. Complications from this procedure include stroke, bleeding and damage to some of the nerves in the neck that can cause a burning or a tingling sensation.

Over the last 15 years, CAS has been increasingly treated with a newer minimally invasive treatment called carotid artery angioplasty and stenting. These procedures do not involve surgery and are performed via small (2mm) nick in the skin of your leg. Using advanced technology and X-ray guidance we can guide a tiny catheter through your blood vessels to your renal artery.

The catheter carries a tiny balloon that can open up the narrowed artery (angioplasty) following which a stent (a soft metal-mesh tube) is placed to help hold the artery open. Although these procedures can be done in an outpatient setting and most patients are admitted overnight for monitoring purposes.