Carotid artery stenting carries higher intermediate- and long-term risks than does carotid endarterectomy, not just higher periprocedural risks, according to the largest and most comprehensive metaanalysis of available evidence from randomized trials to date.
The safety and efficacy of carotid stenting as an alternative to endarterectomy are controversial. Several studies have indicated that stenting is more likely to cause periprocedural stroke, but the data on longer-term outcomes are limited, said Dr. Sripal Bangalore of New York University, New York, and his associates.
In their Oct. 11 online report in the Archives of Neurology, the investigators examined 13 randomized controlled trials that reported outcomes at 30 days or later and included 3,754 patients assigned to stenting and 3,723 to endarterectomy. The mean follow-up in the trials was 2.7 years.
In the short term, stenting was associated with a 31% increase in the risk of periprocedural death, MI, or stroke, compared with endarterectomy. The absolute rates of periprocedural death, MI, or stroke were 5.7% with stenting and 4.7% with endarterectomy, they said.
In the long term, the risk for that composite outcome plus later ipsilateral stroke or death was 19% higher following stenting than it was after endarterectomy. In comparison with endarterectomy, stenting carried a 38% higher risk of the composite outcome of periprocedural stroke or death plus later ipsilateral stroke, a 24% higher risk of the composite outcome of death or stroke, and a 48% increased risk of any stroke.
These increases in long-term risks were consistent across several subgroups of patients: symptomatic or asymptomatic, low risk or high risk, American or non-American, and regardless of whether an embolic protection device was used, Dr. Bangalore and his colleagues wrote (Arch. Neurol. 2010 Oct. 11 [doi:10.1001/archneurol.2010.262]).
However, the rate of periprocedural MI was significantly lower with carotid stenting (0.3%) than with endarterectomy (1.2%). And stenting was associated with an 85% reduction in the risk of cranial nerve injury, all of which occurred in the periprocedural period.
“Our results suggest that the [already known] periprocedural increased risk of carotid artery stenting continues to be seen in the intermediate- to long-term periods as well,” the investigators wrote.
Despite these findings, carotid stenting remains a useful alternative, given that it is less invasive and entails a shorter recovery period than endarterectomy and that it would be beneficial for patients who are poor surgical candidates or at high risk for periprocedural MI. Therefore, “there is an urgent need” to develop the means to select patients who have a low risk of complications with stenting, the researchers added.
One of Dr. Bangalore’s associates reported receiving research grants from AstraZeneca, Bristol-Myers Squibb, Eisai, Ethicon, Heartscape, Sanofi Aventis, and the Medicines Company.