With the International Carotid Stenting Study (ICSS) results giving carotid endarterectomy a definite thumbs-up and hammering a few nails in the coffin for carotid artery stenting, the results of the purist trial CREST have long been awaited for either confirmation, or disagreement of results.
For long, the question has been: Will the CREST trial results be the last nail in the coffin for carotid artery stenting, or will it be what interventional radiologists’ have been hoping for, a shot in the arm for stenting?
The CREST(Carotid revascularisation endarterectomy versus stenting)trial results were announced in late February at the American Stroke Association International Stroke Conference 2010.
Both procedures were shown to be equally safe and effective for the treatment of carotid atherosclerosis and the prevention of stroke, myocardial infarction, and death.
Interventional News asked two prominent interventionists to comment on the CREST results:
James F Benenati, Baptist Cardiac & Vascular Institute and SIR president elect said:
“The CREST results demonstrate that carotid artery stenting is a good and safe alternative to carotid endarterectomy giving patients two options for therapy. Which option a patient chooses should depend on their risk factors and the experience of the operators doing the procedures. While there is a higher minor stroke risk with stenting, the overall complication rates are similar for the two procedures. The IR community has long awaited these results and is enthusiastic to move forward with carotid artery stenting in the proper patients.”
Tony Nicholson,consultant vascular and interventional radiologist at the Leeds Teaching Hospitals NHS Trust said:
“The publication of CREST is timely coming so close to the publication of ICSS. The results of the two studies reflect slightly different methodologies and emphasis. They also remind us that it is rare for any one randomised, controlled trial to give the whole answer and there will always be methodological flaws and differences in interpretation especially where there is equipoise and small differences in results. Both CREST and ICSS are excellent studies but we still need more of their kind in order to eventually meta-analyse the results. It is probably true to say that until we have a robust meta-analysis, we should all continue to work cooperatively in this field, keeping accurate data and entering patients into the best trials available”
In the trial 2,502 patients with either symptomatic (n=1,321) or asymptomatic (n=1.181) carotid stenosis were randomised to endarterectomy or carotid stenting at 117 centres in the United States and Canada over a nine-year period. Patients were an average age of 69 years and were followed for up to four years (median 2.5).
On the composite primary endpoint of any stroke, myocardial infarction or death during the periprocedural period or ipsilateral stroke on follow-up, stenting was associated with a 7.2% rate of these events vs. 6.8% with surgery, a non-significant difference.
However, it was found that, at 30 days, the rate of stroke was significantly higher with stenting, at 4.1% vs. 2.3% with surgery. There was no difference with major stroke, though, at less than 1% in both groups. Conversely, myocardial infarction was higher with carotid endarterectomy, at 2.3% vs. 1.1% with stenting, a statistically significant difference.
Rates of ipsilateral stroke during a mean follow-up of 2.5 years were equal between groups, at 2.0% for stenting and 2.4% with surgery.
Wesley Moore, Los Angeles, United States, who was co-principal investigator on CREST, said, “When considering the combined endpoints of death, stroke, and myocardial infarction, carotid endarterectomy and carotid stent/angioplasty have similar results. However, when death and stroke are considered alone, there are almost twice as many events with carotid stenting/angioplasty as there are with carotid endarterectomy. Nonetheless, the complication rates for both procedures are the lowest reported in the literature to date and suggest that both are safe and effective in the short term of the study to date.”
The age of the patient made a difference, it was found. Younger patients did better with stents and older patients did better with surgery. For patients 69 years and younger, stenting results were superior to surgical results; the younger the patient, the larger the stenting benefit. Conversely, for patients older than 70, surgical results were slightly better than stenting; the older the patient, the larger the surgery benefit.
There were twice as many myocardial infarctions in the surgical group (2.3% compared to 1.1% in the stenting group). There were also more minor strokes (non-disabling strokes that largely resolved) in the stenting group (2.7% versus 1.5% for the surgical group).
The results of CREST have been keenly anticipated since the presentation in 2009 of the ICSS (International carotid stenting study) results, which showed disappointing outcomes with stenting. Martin Brown, London, United Kingdom, who presented the ICSS data at the European Stroke Conference in 2009 has responded to the CREST results. He said, “It is difficult to compare the results of ICSS and CREST directly because ICSS studied only patients in whom the carotid stenosis was recently symptomatic, whereas 47% of patients in CREST were asymptomatic. The CREST presentation did not provide the results separately for the asymptomatic and symptomatic patients. In the combined results they presented, the complication rate of stenting was a little lower in CREST than it was in ICSS, but this is likely to reflect the fact that half the patients had asymptomatic stenosis, which we would expect to have a lower risk of stenting as well as a lower risk of endarterectomy. Otherwise the results look very similar to ICSS in that in CREST there were significantly more procedural strokes in the stenting arm than in the endarterectomy arm (4.1% vs. 2.3%, which was statistically significant). There were more myocardial infarctions in both arms of the trial in CREST than ICSS, but CREST had a different protocol for ascertaining myocardial infarctions, which is likely to account for the difference. I will await the publication of the results of individual endpoints in the symptomatic patients in CREST with interest. In the meantime, I do not believe the results of CREST should alter the conclusion that endarterectomy remains the treatment of choice for symptomatic patients.”
Moore will present the CREST results for the first time to a vascular and endovascular audience at the 32nd Charing Cross International Symposium in London, United Kingdom in April 2010. Of the upcoming presentation, Moore said, “The CREST results are at variance with the European trials and will make for an interesting discussion.”