Medical therapy has benefits in neck artery disease

NEW YORK (Reuters Health) - For people found to have a symptomless buildup of plaque in their neck arteries, intensive medical therapy, not surgery, should be tried first, researchers conclude based on a study they conducted.

For these patients, intensive medical therapy, including aggressive control of blood pressure and cholesterol levels, appears to reduce rates of stroke, heart attack, death and need for surgery. It also curbs the risk of tiny blood clots in the brain arteries that can lead to stroke.

These findings are "hugely important in the US," Dr. J. David Spence told Reuters Health, where roughly 70 percent of carotid (neck) artery surgery and stenting are being performed for symptomless plaque buildup. "Our study shows that 95 percent of that activity is inappropriate," Spence said.

Carotid artery narrowing or "stenosis" is a common finding in older adults, which can lead to a stroke if it is severe. The condition can be treated with surgical removal of the plaque lining the inside of the arteries that cause the stenosis (a procedure called carotid endarterectomy) or with the placement inside the arteries of a stent, a tiny metal tube that maintains an open passage for blood flow. However, the benefit and risks of these procedures for people without symptoms remains hotly debated.

Based on his study, Spence has this advice for the general public: "If someone offers to perform carotid endarterectomy or stenting for your asymptomatic carotid stenosis without first detecting microemboli, you should walk quickly in the other direction."

Spence, from the Stroke Prevention and Atherosclerosis Research Center, London, Ontario, and colleagues studied 468 patients with symptomless carotid stenosis. A total of 199 entered the study between 2000 and 2002, while the remaining 269 joined between 2003 and 2007.

By 2003, the clinic where the study was performed had implemented an intensive medical treatment program for symptomless carotid stenosis. The program involved showing plaque measurements and images to the patients to motivate them to make diet, exercise and other lifestyle changes; more aggressive cholesterol lowering therapy and optimizing blood pressure control. All of the study participants were followed up for at least one year, through July 2008.

Rates of stroke and other cardiovascular "events" dropped with intensive medical therapy. Prior to 2003, the rate of stroke, death, heart attack, or neck artery surgery was 17.6 percent. After 2003, it was only 5.6 percent. Plaque progression in the neck arteries also decreased significantly after implementation of intensive medical therapy.

Moreover, patients who began the study following the implementation of intensive medical therapy were far less likely to have tiny blood clots called microemboli (3.7 percent after 2003 versus 12.6 percent before 2003). This decline in microemboli coincided with better control of cholesterol levels and slower progression of plaque buildup, the researchers report.

However, patients with microemboli had significantly more cardiovascular events in both time periods -- 32.4 percent of patients with microemboli had a stroke or heart attack, died or underwent surgery for symptoms, compared with 8.6 percent of those without microemboli.

The current findings, the researchers say, have direct implications for surgical management of patients with narrowed neck arteries. Intensive medical therapy, not surgery, should be regarded as the first line of therapy for these particular patients, they conclude.

With intensive medical therapy, Spence noted, "less than 5 percent" of patients with symptomless carotid blockages can benefit from surgery or stenting. Surgery or stenting, he added, should only be performed in patients with microemboli.

SOURCE: Archives of Neurology, December 2009.