ARTICLE IN BRIEF
In a trial comparing carotid artery stenting with carotid endarterectomy for treating carotid stenosis, patients who received stents experienced slightly but significantly more strokes, while those who underwent surgery had slightly but significantly more heart attacks at 30 days. But an average of 2.5 years later, there was no significant difference in the number of events between the two groups.
SAN ANTONIO, TX—Carotid artery stenting is as effective and safe as carotid endarterectomy for treating carotid stenosis, according to final results of the highly anticipated Carotid Revascularization Endarterectomy Versus Stenting Trial (CREST).
The study involved 1,321 symptomatic and 1,181 asymptomatic patients from 117 US and Canadian centers who were randomized to receive either carotid artery stenting using the same stent and distal protection devices (Acculink and Accunet devices) or carotid endarterectomy. More than 85 percent of patients in both groups had stenoses of 70 percent or greater. At baseline, the patients were well matched for age, risk factors, and other characteristics.
In the prospective trial, 7.2 percent of those randomized to stenting suffered stroke, myocardial infarction (MI), or death during the periprocedural period or ipsilateral stroke on follow-up an average of 2.5 years later, compared with 6.8 percent of surgery patients, a nonsignificant difference.
The data, described here at the American Stroke Association International Stroke Conference in February, showed that in the weeks after the procedure, patients who received stents experienced slightly but significantly more strokes, while those who underwent surgery had slightly but significantly more heart attacks.
Specifically, the 30-day rate of stroke was 4.1 percent for stenting versus 2.3 percent with surgery. Conversely, the 30-day rate of MI was 2.3 percent for surgery versus 1.1 percent for stenting.
But an average of 2.5 years later, “there was no significant difference in the number of events between the two groups,” with a 2.0 percent rate of ipsilateral stroke among stenting patients and a 2.4 percent rate among surgery patients, said Wayne M. Clark, MD, director of the Oregon Stroke Center and professor of neurology at the Oregon Health Sciences University in Portland. Dr. Clark was the principal investigator from the lead enrolling center for CREST and presented the findings here on behalf of the CREST investigators. However, patients who had an MI reported a better quality of life after recovery than those who had a stroke, he said.
“Both procedures are excellent, with low perioperative rates and apparently excellent clinical durability, so I'm excited to say that I think we have two good options to treat patients,” Dr. Clark said.
The choice may come down to the individual patient's age, health, and preferences, he said.
“When we went into this, I think we thought the less invasive procedure would be best suited for the older patient. Now that we have data from studies in the United States and Europe, we have to question that,” said principal investigator Thomas G. Brott, MD, professor of neurology and director of research at the Mayo Clinic in Jacksonville, Florida.
The study, which was supported by the NINDS with supplemental funding by Abbott (the maker of the stent device), was presented just one day after the International Carotid Stenting Study (ICSS) group reported that surgery was associated with better outcomes than stenting. Reported online Feb. 25 in advance of the print Lancet, interim safety results of the European trial of 1,713 patients showed 8.5 percent of stent patients had a stroke, death, or MI in the first 30 days after surgery, compared with 5.2 percent of the surgery group.
Asked to comment on the disparate results, Dr. Clark intimated that the interventionalists who performed the stent procedures in the North American study were more experienced. “CREST had a very detailed credentialing process. We had a lead in phase where physicians had to do many interventions before they went to the randomized phase,” he said.
There were also differences in the types of stents used, Dr. Clark noted. In the European trial, interventionalists were allowed to use any stent approved by the European Union licensing authorities, while the North American physicians all used Abbott's Acculink Carotid Stent System.
Larry B. Goldstein, MD, director of the Duke Stroke Center at Duke University Medical Center in Durham, NC, who was not involved with either study, said patient selection might have accounted for the differences.
“About half the patients in CREST were asymptomatic and we know the rate of stroke in asymptomatic patients is just of fraction of that of symptomatic patients. Also recent data suggest much lower stroke rates in patients with asymptomatic stenosis treated with medical therapy than was found in studies that were done one to two decades ago. If the background rate is lower, you need a lot more patients to see a difference in outcomes between the two procedures,” he said.
Dr. Goldstein said he is not ready to conclude that the two procedures are equally effective. The ICSS results are more in line with earlier studies that compared the two techniques in symptomatic patients — both of which showed surgery had the edge over stenting, he said, citing studies that were published in 2006 in the New England Journal of Medicine and the Lancet.
As for CREST, “the rate of periprocedural stroke was two times higher with stenting and the rate of periprocedural MI was higher with carotid endarterectomy. That would seem to be a wash out, but stroke seems to carry more long-term consequences than MI,” he said, pointing to the finding that stroke patients had greater impairment in quality of life.
The big unanswered question, Dr. Goldstein said, is how to best treat the asymptomatic patient. “Are the risks of any intervention worth it, or are they outweighed by the benefits of medical therapy?” he asked.
The CREST researchers are now analyzing of-life and economic data and will present those results in the future, Dr. Clark said.
Final results of ICSS, whose primary outcome is the rate of fatal or disabling stroke at three years, are expected in 2012.•
• Mas JL, Chatellier G, Ducrocq X, et al, for the EVA-3S Investigators. Endarterectomy versus stenting in patients with symptomatic severe carotid stenosis. N Eng J Med2006; 355:1660–1671.
• Ringleb PA, Allenberg J, Hacke W, et al, for the SPACE Collaborative Group. 30 day results from the SPACE trial of stent-protected angioplasty versus carotid endarterectomy in symptomatic patients: A randomised non-inferiority trial. Lancet 2006;368:1239–1247.