Next-generation system cleared for SVG treatment in the U.S.
Boston Scientific Corporation has received 510(k) clearance from the U.S. Food and Drug Administration to market its FilterWire EZ Embolic Protection System to treat saphenous vein graft (SVG) disease. The Company plans to launch the product in the United States immediately. Boston Scientific launched the product in Europe and other international markets in September 2003.
The FilterWire EZ System is a low-profile embolic filter mounted on a guide wire and is designed to reduce complications during balloon angioplasty and stenting procedures for the treatment of SVG disease. The FilterWire EX™ System, Boston Scientific’s first-generation embolic protection product, was the first filter-based system cleared for SVG treatment in the U.S. and was launched in June 2003.
The FilterWire EZ system is designed to enhance the effectiveness and ease of use of the product. It features a new “suspended loop” design that supports the filter, allowing for complete vessel wall apposition and for placement in both straight and curved vessels. The system is also 6F guide catheter compatible, and has enhanced deliverability with a 3.2F crossing profile.
“The suspended loop design and the improved deliverability of the FilterWire EZ System have proved to be clinically important improvements,” said David Cox, MD, U.S. Principal Investigator for the BLAZE clinical registry. “In the BLAZE registry, the FilterWire EZ System showed improved rates of procedural success and reduced the risk of Major Adverse Cardiac Events (MACE) compared to previously studied embolic protection systems.”
The FilterWire EZ System was studied in the BLAZE clinical registry, in which the objective was to establish the safety and efficacy of the FilterWire EZ System during balloon angioplasty or stenting procedures in the treatment of SVGs. The BLAZE multi-center registry studied 90 patients at 16 U.S. and six European sites. The primary safety endpoint of the study was the cumulative incidence of MACE, defined as death, Q-wave or non Q-wave myocardial infarction (MI), emergent coronary artery bypass surgery (CABG), or target vessel revascularization (TVR) at 30 days post-procedure. In the BLAZE registry, the incidence of MACE at 30 days was 6.7 percent, compared to 9.9 percent in the FIRE Trial for the FilterWire EX System.
U.S. Medicare backs payment for carotid stents
Guidant Corporation commended the Centers for Medicare & Medicaid Services (CMS) for its intent to expand coverage of carotid artery stenting to include patients receiving FDA-approved carotid stents as part of an FDA-required post-approval study. The U.S. Food and Drug Administration (FDA) approved Guidant's Rx Acculink™ Carotid Stent System and Rx Accunet™ Embolic Protection System. The new devices will provide a minimally invasive treatment alternative to conventional open carotid artery surgery to patients who are at high surgical risk.
Guidant's post-approval studies will include at least 1,500 patients. These studies will provide for the collection of data on the Acculink Carotid Stent System and the Accunet Embolic Protection System when used by a broad group of physicians. Guidant’s devices will be available only to physicians with the appropriate training and experience for performing carotid interventions. The company has worked closely with the FDA, medical societies and leading practitioners to develop targeted training programs for physicians based on experience and skill level with carotid artery stent procedures.
Previously, CMS only covered carotid artery stenting in clinical trials of investigational products not yet approved by the FDA.
CryoPlasty® Therapy Now Available for Limb Salvage
CryoVascular Systems, Inc. has expanded the PolarCath™ CryoPlasty System to include a new line of catheters to treat atherosclerotic occlusive disease in the infrapopliteal and tibioperoneal arteries. The infrapopliteal catheters are used with CryoVascular's PolarCath System, a peripheral CryoPlasty system that treats stenosis by dilating and cooling arteries to -10?C/+14?F with a balloon filled with nitrous oxide. Recently cleared by the FDA, the PolarCath Infrapopliteal Catheter is being used at approximately 100 hospitals across the country.
A prospective, multi-center study (Below the Knee Chill) is also being initiated at 30 hospitals across the country, evaluating the role of the CryoPlasty technology in avoiding major amputation in patients with severe disease. Enrollment began in September 2004, and preliminary results are expected to be presented in early 2005.
Patency at one year for conventional catheter-based interventions is estimated at 59% for PTA and 62% for stenting. The dominant contributing factors affecting the ability to keep the lower extremity arteries open over time is the length of the vessel that is affected as well as whether or not the vessels below the knee have adequate flow. The tendency to treat patients at later stages of disease progression almost always means very long lesions and little, if any, flow below the knee.
Without an effective means to open these small, delicate vessels, many patients ultimately require bypass. Surgical vessel bypass has demonstrated one-year patency rates as high as 83%; however, many times, the vessel used as a bypass conduit is the same one used for coronary bypass. Since most of these patients suffer from systemic vascular disease, preserving the conduit vessels for use in the heart is critical. Additionally, many of these patients have poor overall health and are no longer suitable candidates for a surgical procedure.
Since the launch of the PolarCath System in 2003, physicians using the CryoPlasty procedure as a primary therapy have observed a significant reduction in their use of stents, coinciding with a lower rate of flow-limiting dissection and vessel recoil. Clinical data indicate that 83% of artery blockages treated with the PolarCath System remained open after 9 months.
During a CryoPlasty procedure, a catheter advances a balloon to the site of the occlusion and nitrous oxide, rather than saline, is used to inflate the balloon. The nitrous oxide changes into gas upon entering the balloon, cooling it to -10?C/ 14?F. The cold is believed to have several beneficial vascular effects as it opens the artery, including weakening the plaque to allow it to reshape more easily, reducing vessel elasticity to minimize reclosing of the vessel, and minimizing inflammation and scar tissue formation.
Research presented at the Annual Transcatheter Cardiovascular Therapeutics Scientific Symposium (TCT 2004), showed outcomes of the first patients to receive the therapy. Ninety-five percent of the patients were able to avoid almost-certain amputation below the knee as a result of treatment with the PolarCath System Infrapopliteal Catheter.
“Patients with this type of advanced disease – many of whom are diabetic – have very few treatment options,” said James Joye, DO, director of the Cardiac Catheterization Lab at El Camino Hospital, Mountain View, Calif., and co-founder of the CryoPlasty technique. “The CryoPlasty procedure is a conservative “no harm” therapy that can be employed early in the disease process, and can be repeated if necessary without hindering future treatment options. It may be possible to delay progression of the disease to the limb threatening stage.”
Outcomes of the first patients treated with CryoPlasty reported at TCT: 26 lesions in arteries below the knee were treated in 20 patients who had leg pain at rest or ischemic ulceration and gangrene. All 20 patients received the CryoPlasty technique using the PolarCath System Infrapopliteal Catheter as the primary therapy; 6 patients with severely blocked vessels underwent atherectomy to create a channel that would allow passage of the catheter. Limb salvage with freedom from major amputation was achieved in 19 patients (95 percent) and only 1 patient (5 percent) proceeded to below-the-knee amputation. Five patients (25 percent) underwent toe or transmetatarsal amputation of pre-existing gangrene and 1 patient who was treated for bilateral disease underwent subsequent bypass surgery in one limb.
The PolarCath System is distributed by Boston Scientific Corporation. |
