Medical Device Daily Contributing Writer

SAN ANTONIO – The long awaited results of the widely-heralded landmark Carotid Revascularization Endarterectomy versus Stenting Trial (CREST) were released here Friday and after all was said and done, there was no clear-cut benefit for either approach.

CREST, which was sponsored by the National Institutes of Health (Bethesda, Maryland), enrolled more than 2,500 patients at 117 centers in the U.S. and Canada. The results of this multi-center, randomized prospective study, which took nine years to complete, indicate that either procedure is a good way to limit the risks of having a stroke and that the choice between the two could be more a matter of patient preference than scientific certainty.

Commenting on these results at a press conference here Friday morning, Wayne Clark, MD, a vascular neurologist from Oregon Health Sciences University Medical Group (Portland) said, “I am excited to say that we now have two very good options to prevent stroke.“

Patients were randomized 1:1 to either carotid stenting (CAS) or carotid endarterectomy (CEA), with just over half the patients with symptomatic disease. The primary endpoint was a composite of any stroke, myocardial infarction (MI) or death within 30 days. The secondary endpoints contrast CEA and CAS by symptomatic events, sex, restenosis and health-related quality of life (QOL) and cost.

Based upon a mean follow-up of about 2.5 years, the two procedures were quite similar with regard to the primary endpoint. In the peri-procedural period the stroke rate for CAS was 4.1% vs. 2.3% for CEA patients, whereas the MI rate was lower for CAS at 1.1% vs. 2.3% for CEA.

A difference was noted for age variations. For patients less than 69 years old, the outcome for CAS was slightly better, whereas for patients older than 70 years, the results for endarterectomy were superior. This benefit increased the older the patient's age.

Lead CREST investigator Thomas Brott, MD of the Mayo Clinic (Jacksonville, Florida) indicated that while the stroke and heart attack rates were different “unfortunately, there is not a lot of scientifically valid information that tells us which is more important to the patient.“

One of the key observations of this trial is that the overall stroke rate for both arms of the study was remarkably low and Brott thought that this may have been due to the “rigorous credentialing lead-in phase to train and evaluate interventionalists.“ The trial employed both a stent and an embolic protection.

Responding to a question on this topic from Medical Device Daily, Brott speculated that these stellar results would likely not be seen in the community setting, because interventionalists might not be as well-trained as the CREST investigators and also may not be performing as many cases.

According to Steven Schiff, MD, medical director of Invasive Cardiovascular Services at Orange Coast Memorial Medical Center (Fountain Valley, California), who was not involved in the study, “this was the lowest rate of adverse events ever reported in a stroke trial.“

Clark noted that QOL and health economics had been gathered in the trial, but would were not available at this time.

Ironically, the CREST results were reported on the heels of the interim safety data at 120 days of the European International Carotid Stenting Study (ICSS), which appears to favor carotid endarterectomy over carotid stenting for patients with symptomatic carotid stenosis. These results of ICSS and those of the ICSS magnetic resonance imaging (MRI) sub study were published online Feb. 26 in The Lancet and The Lancet Neurology, respectively.

ICSS was a multicenter, international randomized controlled trial comparing carotid artery stenting with carotid endarterectomy in patients with recently symptomatic carotid stenosis. The trial enrolled 1,713 patients, with 855 randomized to stenting and 858 randomized to surgery.

Its results show higher rates of stroke, death, or peri-procedural MI in patients treated with stenting versus endarterectomy. The primary outcome of the study is the three-year rate of fatal or disabling stroke. The final results are expected to be available in 2012.

With the ICSS and CREST results, there are now four large randomized trials that have reported results evaluating the use of carotid stenting as an alternative to endarterectomy to treat symptomatic carotid artery stenosis.

The Stent-Supported Percutaneous Angioplasty of the Carotid Artery versus Endarterectomy (SPACE) trial showed that carotid stenting failed to meet criteria for non-inferiority versus endarterectomy. The Endarterectomy versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis (EVA-3S) trial results, which were released within two weeks of the SPACE trial, also failed to show non-inferiority with carotid stenting versus endarterectomy. Stroke and death rates were again lower with surgery.

Commenting on the CREST and ICSS results, Karl Illig, MD, a cardiologist at the University of Rochester Medical Center (Rochester, New York) noted that “neither of the studies show a home run for either procedure.“ He continued, “I will bet you that people who are at low risk for surgery will continue to undergo surgery and people at high risk will undergo stenting.“

Another perspective on these results was provided by interventional cardiologist Gary Roubin, MD, of Lenox Hill Hospital (New York) who said that “It doesn't surprise me that we got better results with stenting in the U.S., where we have had much broader experience. North American surgeons do the job better,“ he said.

Roubin is one of the co-authors of CREST.