Carotid Stenting With Embolic Filter Confirms Superior Safety

Peggy Peck

September 18, 2003

Sept. 18, 2003 (Washington) — Among high-risk patients, carotid artery stenting with distal protection is associated with a lower 30-day adverse event rate than carotid endarterectomy, according to results from the Registry Study to Evaluate the NeuroShield Bare Wire Cerebral Protection System and X.act Stent in Patients at High Risk for Carotid Endarterectomy (SECURITY), a prospective, multicenter registry.

Patrick Whitlow, MD, from the Cleveland Clinic Foundation in Ohio, presented the results here Wednesday at a late-breaking clinical trials session at the 15th Transcatheter Cardiovascular Therapeutics meeting (TCT 2003).

The primary end point of the study, which included a total of 305 high-risk surgical patients, was stroke, myocardial infarction, or death at 30 days. According to Dr. Whitlow, "7.2% of patients reached this end point, which compares favorably with the 11% to 15% 30-day historical event rate from the carotid endarterectomy studies." The composite end point plus ipsilateral stroke will also be measured between 30 days and one year.

Gishel New, MBBS, PhD, director of cardiology at Box Hill Hospital in Victoria, Australia, told Medscape that the SECURITY results, on top of positive reports from the Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) and Acculink for Revascularization of Carotids in High-Risk Patients (ARCHeR) trials, indicate that the "future belongs to carotid stenting."

"It makes sense, if you can do a procedure safely and have the patient up and walking within hours, home the next day, rather than a five-day hospital stay, who wouldn't chose stenting?" Dr. New said. She was not involved in the study, but she chaired a TCT press conference where the SECURITY data were discussed. "Endarterectomy has been the gold standard, but I think that is likely to change," she said.

Enrollment criteria included symptomatic carotid stenosis 50% or higher or asymptomatic carotid stenosis of 80% or higher, both measured by angiogram. All patients had at least one additional high-risk criteria, eg, unstable angina, ejection fraction less than 30%, need for dialysis because of renal failure, uncontrolled diabetes, restenosis after prior endarterectomy, coronary artery bypass graft with valve replacement in the previous 30 days, or surgically inaccessible lesions. Patients enrolled in SECURITY were considerably older than previous patient populations evaluated in carotid artery stenting studies; 40% of the patients were older than 70 years and 28% were 80 or older.

Distal protection filters, designed to trap particle debris to prevent emboli during stent placement, were used in the study. Thus far, of the 143 filters analyzed, "embolic debris was present in 66% of filters, platelets and fibrin were identified in 23%, so debris was recovered in 89% of the filters," Dr. Whitlow reported.

The SECURITY results were presented the same day that investigators for SAPPHIRE presented 12-month results. (Thirty-day results from the SAPPHIRE trial had been presented at the American Heart Association 2002 Scientific Sessions.) Unlike SECURITY, SAPPHIRE is a head-to-head randomized trial comparing endarterectomy with stenting. SAPPHIRE included patients who were less high-risk than SECURITY patients.

The results demonstrated that the 30-day adverse event rate was 50% lower with stenting than with endarterectomy, making SAPPHIRE the first study that demonstrated an interventional procedure is superior to surgery. SAPPHIRE principal investigator Jay S. Yadov, MD, also from the Cleveland Clinic Foundation, called the trial "a watershed medical event."

The 30-day adverse event rate in SAPPHIRE was 5.8% for the stent, which used the AutoGuard filter, and 12.6% for surgery ( P < .05). After 12 months, the results continue to favor stenting, Dr. Yadov said Tuesday. The 12-monthmajor adverse event rate was 11.9% in patients randomized to stenting compared with 19.9% in patients randomized to endarterectomy. Moreover, the individual end points showed comparable or better results for stented patients than for endarterectomy patients, Dr. Yadov said.

TCT 2003: Late-Breaking Clinical Trials-3 — SECURITY; Carotid Stenting Trials — SAPPHIRE. Presented Sept. 17, 2003.

Reviewed by Gary D. Vogin, MD