February 1, 2011
Test For Blocked Neck Arteries Only Necessary For People With Stroke Risk Factors
Study Highlights:* New multi-agency guidelines recommend against widespread screening for blocked neck arteries, using ultrasound to detect the condition only in people with symptoms or other stroke risk factors.
* For people with severely narrowed neck arteries, especially when stroke warning symptoms have occurred, either surgery or inserting a stent is a reasonable approach to reducing stroke risk.
Widespread screening or routine ultrasound for blocked neck arteries to determine stroke risk isn't necessary, according to new guidelines from the American Heart Association/American Stroke Association, American College of Cardiology and other groups.
Carotid endarterectomy and carotid stenting are reasonable and effective ways to treat blocked neck arteries, though some patients may be a better candidate for one procedure over the other, the guidelines also state.
When the carotid arteries on the side of the neck or vertebral arteries alongside the spinal column become clogged, less blood gets to the brain and the risk of stroke increases.
The guidelines writing committee, which included a wide range of specialists on stroke prevention, agreed there isn't sufficient evidence of benefit for widespread screening. "However, if your doctor hears abnormal blood flow when listening to your neck arteries, or if you have two or more risk factors for stroke (such as high cholesterol or a family history), then it is a reasonable approach," said Jonathan L. Halperin, M.D., co-chair of the writing committee and Professor of Medicine at the Mount Sinai School of Medicine in New York.
"The guidelines will provide new information and evidence to help clinicians select treatment approaches with their patients," said Thomas G. Brott, M.D., committee co-chair, Professor of Neurology and director of research at the Mayo Clinic campus in Jacksonville, Fla.
Stroke risk factors include age, family history of stroke, high blood pressure, high blood cholesterol, diabetes, obesity, atrial fibrillation, physical inactivity, sickle cell disease and other heart or blood vessel diseases.
Among dozens of recommendations, the writing group also noted that two often competing procedures are used to restore adequate blood flow to the brain past severely narrowed arteries. In carotid endarterectomy, used for half a century, plaque buildup is surgically removed. In stenting, which has been available for about 15 years, a balloon catheter is inserted to open the vessel and a metal mesh tube (stent) is left in place to keep the blood vessel open.
After reviewing the evidence, including two recent head-to-head comparisons, the writing committee concluded that both approaches are reasonable and safe when arteries are more than 50 percent blocked.
"The guidelines support carotid surgery as a tried-and-true treatment for most patients," Brott said. "However, for patients who have a strong preference for less invasive treatments, carotid stenting offers a safe alternative. Because of the anatomy of their arteries or other individual considerations, some patients may be more appropriate for surgery and others for stenting."
Furthermore, medications offer a better alternative than either surgery or stenting for many patients, according to the guidelines. In the latest clinical trials comparing the procedures, all patients received optimal medical treatment and there were no medication-only groups.
"The risks of these procedures have fallen considerably, but you need to make sure you have very experienced practitioners performing the latest techniques," Halperin said.
The full text of the guidelines will be published in Circulation: Journal of the American Heart Association; Stroke: Journal of the American Heart Association, and Journal of the American College of Cardiology. The guideline executive summary will be in Catheterization and Cardiovascular Interventions, Journal of Cardiovascular Computed Tomography, Journal of NeuroInterventional Surgery, Journal of Vascular Surgery, and Vascular Medicine.
The guidelines were developed with the American Association of Neuroscience Nurses; American Association of Neurological Surgeons; American Society of Neuroradiology; American College of Radiology; Congress of Neurological Surgeons; Society for Atherosclerosis Imaging and Prevention; Society for Cardiovascular Angiography and Interventions; Society of Interventional Radiology; Society for NeuroInterventional Surgery; Society for Vascular Medicine; and Society for Vascular Surgery.
The American Academy of Neurology and the Society of Cardiovascular Computed Tomography collaborated in the process.
Co-authors on the writing committee are: Suhny Abbara, M.D.; J. Michael Bacharach, M.D.; John D. Barr, M.D.; Ruth L. Bush, M.D., M.P.H.; Christopher U. Cates, M.D.; Mark A. Creager, M.D.; Susan B. Fowler, Ph.D.; Gary Friday, M.D.; Vicki S. Hertzberg, Ph.D.; E. Bruce McIff, M.D.; Wesley S. Moore, M.D.; Peter D. Panagos, M.D.; Thomas S. Riles, M.D.; Robert H. Rosenwasser, M.D.; and Allen J. Taylor, M.D.
Author disclosures are on the manuscript.
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