Thirty-day results from the SPACE trial failed to demonstrate the
noninferiority of stenting.
In
patients with moderate-to-severe symptomatic carotid stenosis and
recent ischemic events, guidelines consistently recommend carotid
endarterectomy (CEA), but carotid angioplasty and stenting (CAS) is
an increasingly popular alternative. However, a systematic review of
five small randomized trials did not show a significant difference in
outcomes between endarterectomy and stenting, and another recent
trial, "EVA-3S," was stopped early when an interim analysis
showed significantly higher 30-day risk with stenting (Journal
Watch Oct 18 2006).
In
the "SPACE" trial, European researchers undertook a separate effort
to establish whether CAS is noninferior to CEA. They randomized 1183
patients — all with onset of neurologic or ocular symptoms within
the past 180 days and ipsilateral carotid stenosis of at least 70% on
ultrasound — to receive either CAS or CEA within 14 days. Rates of
the primary outcome — ipsilateral stroke or death from any cause
during the 30 days after treatment — were not significantly
different between the groups (6.8% for CAS vs. 6.3% for CEA).
According to a predefined statistical analysis, the trial failed to
show that CAS was noninferior to CEA. Nonsignificant trends favored
CEA on six of eight secondary endpoints.
Comment: These results are
ambiguous. An editorialist predicts that interventionists will
emphasize the similar outcomes in the two groups, while surgeons will
stress the failure to prove the noninferiority of stenting and the
trends favoring endarterectomy. The authors will eventually report
longer-term outcomes from the "SPACE" trial; larger studies
such as the "CREST"
trial and meta-analyses may also help shed light on this
controversy.
— Bruce Soloway, MD
Published in Journal Watch October
24, 2006
Citation(s):
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 Oct 7; 368:1239-47.