Carotid Artery Stenting Still Controversial

Carotid Artery Stenting Still Controversial

By Amy Selwyn

New York—An estimated 200,000 carotid endarectomies to prevent stroke are performed every year in the United States. Despite the FDA’s approval of the first carotid artery stent (CAS) in (Oct?) 2004 as a less invasive alternative to carotid artery endarterectomy (CAE), and despite clinical trial data showing equivalence in outcomes between the 2 procedures, controversies about CAS persist.

Investigators on both sides of the question spoke out at the 31st annual Veith Symposium, sponsored by the Montefiore Medical Center, Albert Einstein College of Medicine, New York.

Because CAE is an established, safe, and effective treatment, most CAS clinical trials have included only patients who were not considered candidates for open surgical repair.

The SAPPHIRE (Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy) study was the first multicenter, randomized trial comparing CASwith an embolic protection device, the RX Acculink system (Guidant), with CAE. The primary end point was the rate of major adverse events—a composite of stroke, myocardial infarction (MI), or death within the first 30 days, or stroke or death between 31 days and 12 months following the procedure.

“The SAPPHIRE trial data indicated that patients undergoing carotid stenting do as well or better than those undergoing endarterectomy,” said Kenneth Ouriel, MD, of the Cleveland Clinic. Stenting was at least as effective as surgery in restoring carotid artery blood flow, with a lower incidence of associated major events (ie, 12.2% for state placement vs 20.1% for endarterectomy at 1 year).

The RX Acculink stent is indicated in patients who have had symptoms of a stroke or those with carotid arteries at least 80% occluded who are not candidates for surgery. Approval was based in part on results of the ARCHeR trial (Acculink for Revascularization of Carotid in High-Risk Patients): ARCHeR 1 patients received a stent only; ARCHeR 2 patents received a stent plus Accunet embolic protection filter; ARCHeR 3 patients received a newer version of the catheter for delivery of the stent and the RX Accunet embolic protection device.

The 1-year data for ARCHeR 1 and 2, using the composite end point of 30-day event rate for stroke, MI, and death plus ipsilateral stroke up to 12 months, show that the major event rate was 8.3% and 10.2% for ARCHeR 1 and 2, respectively.

“The SAPPHIRE trial reported equivalence of carotid stenting and carotid endarectomy. But a significantly higher proportion of CAS patients had prior coronary artery bypass surgery and/or coronary angioplasty, biasing MI results in favor of CAS,” said Anthony M. Camorota, MD, of Jobst Vascular Center, Toledo, Ohio. ARCHeR results showed a 30-day stroke/death rate of 6.6%; however this increased to 9.5% in patients with significant atherosclerotic disease. But antherosclerotic patients on dialysis had a 29% stroke/death rate during this period.

“A trial analyzing CAS versus best medical care, including symptomatic and asymptomatic patients, is mandatory, since the number of patients who will undergo CAS in the future will dwarf the number of patients ever treated by CAE,” Dr Comerota predicted.

So far efficacy of carotid stenting has not been confirmed for patients at lower surgical risk. An ongoing trial, CREST (Carotid Revascularization vs Stenting Trial) is comparing efficacy of CAS and CAE for the prevention of recurrent stroke in patients who have had a transient ischemic attack or mild stroke.

Robert W. Hobson III, MD, of the University of Medicine and Dentistry of New Jersey, reported preliminary findings assessing the association of age and periprocedural stroke and death in patients undergoing CAS. An increasing proportion of patients suffered stroke or death with increasing age (ie, 1.7% of patients <60 years, 12.1% of those ³80 years).

“Pending results from randomized studies, care should be taken in performing CAS in older populations,” Dr Hobson said.