FDA approves new carotid stent system, Protégé Rx

This product is unique in design with radiopaque markers for visualization.

The FDA approved a new carotid stent system, Protégé Rx, for the treatment of carotid artery disease in patients who are at high risk for adverse events from carotid artery surgery.

“This product appears to be an improved third generation of embolic protection stenting and allows for greater control of the interventional procedure,” said Gary Ansel, MD, clinical director of peripheral vascular intervention in the department of cardiology at Riverside Hospital, Ohio.

The FDA reached its decision based on data from the CREATE (Carotid Revascularization with ev3, Inc. Arterial Technology Evolution) pivotal trial. This trial demonstrated the safety and efficacy of the Protégé Stent System (ev3 Inc.) when used with the SpideRx Embolic Protection Device (ev3 Inc.), and it showed the product to be a reasonable alternative for revascularization among patients with severe carotid stenosis and high-risk features for carotid endarterectomy.

“The FDA was pleased with the fact that there was equivalency to the already approved device,” Ansel told Cardiology Today.

CREATE trial results

Angiogram image of the ev3 Protégé Rx stent K. Mathias, MD, department of radiology, Klinikum Dortmund, Germany

CREATE was a prospective, nonrandomized study at 31 centers in the United States. The researchers performed carotid artery stenting with the ProtégéRx self-expanding nitinol stent and the Spider embolic protection system in 419 patients.

The CREATE trial compared favorably with performance criteria that the researchers established, based on the results of previous carotid stenting trials. Technical success was observed in 97.4% (n=408) of the patients, according to preliminary data from CREATE published in the Journal of the American College of Cardiology.

Ansel and colleagues observed a combined incidence of major adverse cardiac and cerebrovascular events at 30 days after intervention in 6.2% of patients, of which 1.9% died, 3.3% had a nonfatal stroke and 1% had a nonfatal MI. Predictors of these factors included duration of filter deployment, symptomatic carotid stenosis and baseline renal insufficiency, according to the trial data.

One limitation to these findings is that this device was approved without a randomized trial and has not been tested against other currently available stents, according to R. David Anderson, MD, MS, associate professor of medicine and director of Interventional Cardiology, University of Florida Health Science Center. However, he said, the FDA approved other stents without these comparisons and any technological advance that makes a procedure easier to perform has the potential to improve outcomes.

“The CREATE trial highlighted this point by demonstrating better outcomes with reduced filter deployment times. This variable is strongly related to patient selection, but a device that is easier to use, visualize and deploy would be a welcomed advance in the field,” said Anderson, an editorial board member of Cardiology Today. “I would not hesitate to use this product or recommend its use in appropriately selected patients. The CREATE trial demonstrated outcomes that are consistent with prior carotid stent studies providing a level of comfort for the interventionalist using this technology.”

Benefits of Protégé

Traditionally, carotid artery disease is treated with endarterectomy; however, for the many patients who are at high risk for surgery, carotid stenting evolved as a viable option.

The Protégé Rx is unique in its design. For example, it is the only currently available stent that includes radiopaque markers for visualization. Other approved stents may be prone to movement during delivery. They are also not available in a tapered format, whereas Protégé Rx is available in both straight and tapered configurations to provide a variety of options to address a broad range of differences in proximal and distal reference vessel size.

Protégé Rx straight and tapered stents. Courtesy of ev3

“The device itself is low profile and similar to others that are out there, but it was mainly an easier deliverability feature that makes it more beneficial,” Ansel said. “It allows us to utilize whatever wire we’re comfortable with.”

The rapid exchange platform allows for a single physician to operate the device compared with over-the-wire designs that require multiple operators. It is also compatible with 6F catheters. The SpideRx Embolic Protection Device is the only available distal filter embolic protection device that allows physicians to use their guidewire of choice. The FDA previously cleared it for use in both carotid arteries and saphenous vein grafts.

“Overall, this device [Protégé Rx] appears to have some advantages over currently available technology,” Anderson said. “It appears to be easier to deliver and visualize, is available in a tapered format that better lends itself to variations in carotid anatomy, and is available in a wide variety of sizes with the rapid exchange format. It is the only available device that allows individual guidewire selection by the user.”

The product is recommended for use in patients with increased surgical risk, those with significant comorbidities, such as heart and lung disease, or anatomical features that makes surgical endarterectomy an increased risk, such as post-radiation and previous endarterectomy.

“So far, none of the carotid stents have shown any significant risk for recurrent disease and not being able to protect the patient from future stroke,” said Ansel, who was “very happy” with the product when he used it.

In addition to the United States, the Protégé Rx Stenting System is commercially available in Canada, Europe and several countries in Latin America and Asia. – by Tara Grassia

For more information:

• Safian RD, Bresnahan JF, Jaff MR, et al. Protected carotid stenting in high-risk patients with severe carotid artery stenosis. J Amer Coll Cardiol. 2006;47:2384-2389.