Distal Protection Makes a Difference
Study finds carotid stenting with distal protection safer than endarterectomy at 30 days.
To view the Table 1 for this article, please refer to the print version of our January/February 2003 issue, page 25.
The first randomized, multicenter trial to compare high-risk patients undergoing either carotid endarterectomy (CEA) or stenting with embolic protection has found lower complication rates for the less-invasive stent procedure. Thirty-day results of the Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) trial were presented in a late-breaking clinical trial session at the 75th Scientific Sessions of the American Heart Association by investigator Jay Yadav, MD, Director of Cardiovascular Medicine at the Cleveland Clinic Foundation in Cleveland, Ohio.
Patients randomized to stenting received Cordis Precise nitinol stents (Cordis Endovascular, a Johnson & Johnson company, Miami, FL) (Figure 1) in conjunction with the company’s AngioGuard XP distal protection device, an intra-arterial strainer with 100-micron-sized pores developed by Dr. Yadav (Figure 2). Surgeons participating in the study had performed a median of 30 procedures annually, with mean complication rates of 1%. The interventionalists taking part in SAPPHIRE had each performed a median of 64 carotid stenting procedures annually with similar 1% complication rates.
A team that included a neurologist, a surgeon, and an interventionalist examined each of the prospective enrollees (n=723). Patients that the team deemed inappropriate for surgical treatment were entered into a stent registry (n=409); those patients assessed as inappropriate for stenting were entered into a surgical registry (n=7). Patients judged acceptable for both surgery and stenting were randomized at 30 centers, with 151 people undergoing CEA and 156 others receiving stents. Follow-up was scheduled for 30 days, 6 months, and annually for 3 years. The primary endpoints were death, any stroke, MI at 30 days postprocedure, and 30-day MACE (major adverse clinical events) plus death and/or ipsilateral stroke between 31 days and 1 year postprocedure.
Patients with one or more of the following morbidities were considered high risk: 1) congestive heart failure (class III/IV) and/or known severe left ventricular dysfunction (ejection fraction <30%); 2) open heart surgery needed within 6 weeks; 3) recent MI (>24 hours, <4 weeks); or 4) unstable angina (CCS class III/IV). Exclusion criteria included current stroke (<48 hours), total occlusion of the target carotid artery, other planned surgical or percutaneous interventions (within 30 days), and ostial lesions of the common carotid artery.
Although patient groups were similar in many respects in the randomized cohort, Dr. Yadav noted that significantly higher rates of coronary artery disease and prior CABG placed the stent group at higher risk. Furthermore, comparing stent registry patients (n=408) to all randomized patients (n=307) showed significantly higher rates of high-risk features for the stent registry.
Reporting 30-day results, Dr. Yadav said that device success rates (residual stenosis <30%) were 91.2% and 91.3% for the stent randomized and registry arms. Delivery and retrieval of the distal protection device was successful in more than 98% of both stent groups as well. More than 60% of the guidewire baskets contained embolic debris upon retrieval.
Combined primary endpoint rates of 30-day death, stroke, or MI were measured at 5.8% for the stent group and 12.6% for CEA—a significant difference (P=0.047). Individually, all three components trended in favor of the stent group (Table 1).
Analysis separating symptomatic and asymptomatic patients showed trends favoring the stent group for the primary endpoint (symptomatic 4.2% vs 15.4%; asymptomatic 6.7% vs 11.2%). Combined death, stroke, and MI rates were 7.8% for the 408 stent registry patients, and 14.7% for the 7 patients in the surgical registry.
The 30-day in-hospital MACE rate advantage for the stent group approached significance (4.5% vs 10.6%, P=0.051). Out-of-hospital rates were 1.3% vs 2.0% (P=0.68). The stent registry rates were 3.9% for both in-hospital and out-of-hospital (no rate for the 7 patients in the surgical group). Although TIA and major bleeding rates trended in favor of the stent group, cranial nerve injury rate was significantly in favor of the stent group (0.0% vs 5.3%, P<0.01).
“These results are preliminary,” said Dr. Yadav, “but the 30-day data are a good barometer of long-term results. Most procedure-related adverse events in carotid artery interventions occur within this timeframe.” He estimates that approximately 30% of the 200,000 patients undergoing carotid procedures annually would be eligible for stenting.
David Holmes, MD, an American Heart Association discussant and cardiologist at the Mayo Clinic in Rochester, Minnesota, described SAPPHIRE as “scientifically sound” and “important.” He added, “The thing that patients fear more than MI is stroke. This is a public health issue.” Dr. Holmes pointed out that complication rates were low for both stent and surgical groups. “The surgery was excellent,” he said, “but it just happened that the interventional cardiology was more excellent. In expert hands, these patients now have a better and less-invasive option.” He cautioned, however, that the relative benefit of stenting among lower-risk patients still needs to be tested. The long-term outcome and need for reintervention for restenosis are also yet to be determined.
Walter Alexander is a freelance medical journalist in New York.