CHICAGO – Carotid endarterectomy is safer than stenting when lesions have greater complexity based on length, location, and presence of sequential lesions, according to a subanalysis of the CREST study.
Previous studies have shown that carotid artery stenting (CAS) is also risky in patients with type 3 aortic arches; atherosclerotic aortic arches; internal carotid artery tortuosity; circumferential calcification; and ulcerated lesions.
Taken together, “we can now begin to populate a list of conditions that are high risk for carotid artery stenting. For patients with these factors, we would strongly recommend that carotid endarterectomy be employed rather than carotid artery stenting,” said CREST (Carotid Revascularization Endarterectomy versus Stent Trial) investigator Dr. Wesley Moore, professor and chief, emeritus, of the division of vascular surgery at the University of California, Los Angeles.
“However, in the absence of these higher risk characteristics, carotid artery stenting should yield results equivalent to carotid endarterectomy,” he said at a meeting hosted by the Society for Vascular Surgery.
CREST demonstrated that carotid artery stenting carries about twice the risk of stroke and death (4.4%) as carotid endarterectomy (2.3%); the investigators revisited their subjects’ preop angiograms to see if lesion characteristics were to blame in a subanalysis of the trial results.
In CREST, 438 patients had angiograms before carotid endarterectomies (CEA), about a third of the total number of CEA patients, while preop angiograms were done in all of the 1,262 CAS patients. There were no statistically significant differences in age, gender, stenosis symptoms, smoking history, arrhythmias, and left ventricular hypertrophy between CEA and CAS patients.
For lesions longer than 12.85 mm – the median length in CREST – the combined outcome of strokes and death occurred in 1.9% of CEA and 6.1% of CAS patients (CAS odds ratio, 3.45; 95% confidence interval, 1.21-9.83). For sequential lesions, strokes and death occurred in 0.7% of CEA and 5.8% of CAS patients (CAS OR, 9.21; 95% CI, 1.23-68.94).
With long, sequential lesions distal to the carotid bulb, stroke and death occurred in 6.3% of CAS patients but no CEA patients, giving an “infinite odds ratio in favor of CEA,” Dr. Moore said.
Two-thirds of all the patients in CREST had lesion risk factors for CAS, which might help explain the original findings.
CREST also found that stenting was riskier in older people and women, but it seems likely now that age and gender were surrogates for adverse lesion characteristics.
“The fact of the matter is that older patients have more complex lesions, so age tended to be a surrogate for lesion complexity. If I have an 80-year-old with a short, isolated lesion, I don’t think the fact that they are 80 represents higher risk. I think the lesion being short puts them in the same low risk [category] as other favorable CAS characteristics. I think that’s also true for gender,” Dr. Moore said.
Angiograms almost always underestimate the length of carotid lesions. CT and MRI do a better job, but “ultrasound may be even better than those two,” he noted.
CREST was funded by the National Institutes of Health and Abbott Vascular Solutions. Dr. Moore has no disclosures. Other authors reported relationships with Abbott, Medtronic, Boston Scientific, and other companies.