When a person's blood vessels narrow, the condition is called atherosclerosis. And when it happens in the carotid artery, it is also known as carotid artery disease.

The carotid arteries are two large blood vessels—one on each side of the body—that transport blood, oxygen and nutrients from the heart to the brain, face and neck. If those arteries become clogged with fatty substances and cholesterol, also known as plaque, it can be harder for blood to get to the brain, increasing a person’s risk of stroke.

Doctors at Yale Medicine are well versed in diagnosing and treating this potentially life-threatening condition, either with surgery or with an X-ray assisted technology called stenting.

Carotid artery disease may be suspected if a doctor hears a whooshing sound (called a bruit) while listening to a patient’s neck with a stethoscope during a checkup. A stroke or a mini-stroke (also called a transient ischemic attack or TIA) can also be a sign that a person’s carotid artery is narrowed or blocked. Dizziness, numbness, weakness or a severe headache may be signs of a TIA caused by a blocked carotid artery.

Patients in whom carotid artery disease is suspected are usually tested using a carotid Doppler ultrasound. This is a painless, harmless test that uses sound waves to create an image of the carotid arteries and the plaque inside them. Ultrasound is the preferred diagnostic tool, because it does not expose patients to unnecessary radiation. Usually, it provides a clear enough picture to identify a blockage and determine a treatment plan.

But occasionally, other scans such as magnetic resonance imaging (MRI), carotid angiography (a special type of X-ray) or computerized tomography (CT) are also needed. Before angiography or CT scans are performed, patients have contrast dye injected into the bloodstream so that their arteries show up clearly on the images.

A carotid artery shown to have at least 70 percent stenosis, or narrowing, should be opened up. That can either be done with a surgical procedure called carotid endarterectomy, or with a minimally invasive procedure called carotid artery stenting, where a stent—a small mesh tube—is inserted into the artery to open up the artery.

Carotid artery stent placement was previously used only for patients considered too old or too sick to have surgery under general anesthesia, or who had previously had carotid artery surgery. But in recent years, the procedure has become an option even for people who can have surgery.

“It is no more expensive than surgery, and is safer than surgery in many patients, so increasingly people have been choosing stents over surgery,” says Gowthaman Gunabushanam, MD, a radiologist in the Department of Radiology & Biomedical Imaging. “Newer evidence suggests that the results from stent placement are effectively equivalent to that of surgery.”

This procedure is done by a vascular specialist. Patients are given local anesthesia at the incision site, and a sedative to relax them. A tiny cut is made in the groin, and a catheter is advanced through the groin artery to the neck, and contrast dye is injected through it. The doctor uses X-ray technology, called fluoroscopy, to view moving pictures of the arteries through the body.

“We take X-rays before and after the contrast dye is injected,” Dr. Gunabushanam says. “Then the computer subtracts the ‘before’ images from the ‘after’ images, so we get a very clear, high-resolution picture of exactly where the dye is going.”

Using the fluoroscopy as a guide, the doctor then threads a tiny catheter through the artery all the way up to the blockage in the neck. A wire with a tiny balloon on the end is also pushed through the catheter to the blockage site, along with a wire mesh stent.

The balloon is inflated, compressing the stent against the plaque in the artery walls and opening blood flow back up. The balloon is then deflated and removed, leaving the stent in place. Carotid artery stenting can take up to 1 to 2 hours to perform, depending on disease severity and a patient’s individual anatomy. Because this procedure doesn’t involve major surgery, patients can usually go home the same day or the next morning.

Patients may have to limit their movement for a few days after an angioplasty as the small incision in their groins heals. They will also need follow-up ultrasounds every few months at first, and then every year, to make sure their arteries are not becoming narrowed or blocked again.

To reduce the risk of further blockages, patients should eat a healthy diet, not smoke, and take any blood pressure, cholesterol, or diabetes medication their doctor prescribes them. They may also be prescribed aspirin or a blood-thinning medicine on a regular basis, to keep clots from forming.

For both surgery and stent placement for carotid artery disease, adequate operator training and experience are critical for the safe and effective performance of the procedure. At Yale Medicine, doctors from radiology, cardiology and vascular surgery meet regularly to discuss individual cases of carotid artery disease and the best treatment options for each patient. Patients also have access to clinical trials for carotid artery disease through Yale Medicine’s Non-Invasive Vascular Imaging.