Atherectomy devices in new trials


Two new trials have been established in the US to assess atherectomy devices in treating the peripheral arteries. The first patient has been enrolled in the CELLO (CliRpath Excimer Laser System to Enlarge Lumen Openings) trial, which is an FDA-approved pivotal IDE trial that will assess the TURBO-Booster catheter (Spectranetics) in achieving atherectomy when treating larger diameter superficial femoral arteries. The trial will enrol 85 patients at up to 15 sites. The company also plans to initiate a patient registry of approximately 100 patients at multiple centers in the US and Europe. Spectranetics hopes to obtain device clearance in 2007.

The first patient enrolled in the trial was a 72-year-old female suffering from severe, life-style limiting claudication. The artery treated was 6mm in diameter and was 85% stenosed prior to the procedure. Following multiple passes with the TURBO-Booster device, the stenosis was reduced to 25%. The results of the procedure were sufficient for a stand-alone case result that did not require further adjunctive treatment with other devices.

Dr David Allie, a CELLO investigator at Southwest Medical Center in Lafayette, LA, commented, “The Spectranetics TURBO-Booster opens the realm of vessel treatment to include vessels much larger than those treated by existing laser technology, and has the potential to treat every vessel from the groin to the toes using the laser.”

Spectranetics has recently initiated two feasibility clinical trials using its laser technology in below-the-knee lesions and acute limb ischemia. The company has also initiated a post-market study measuring the lumen size created by its recently launched 2.5 Turbo catheter.

John G Schulte, Spectranetics’ president and CEO, stated, “Since we believe that above-the-knee procedures represent nearly 70 percent of all endovascular procedures performed in the legs, our market opportunity is significantly expanded if the CELLO trial is successfully completed and the TURBO-Booster receives FDA clearance.”

Separately, the FDA has approved the expansion of the OASIS (Orbital Atherectomy System for Treatment of Peripheral Vascular StenosIS) clinical trial following a review of the safety data from the feasibility phase of the study. The trial is expected to enrol a total of 124 patients at up to ten centers.

The OASIS trial, sponsored by Cardiovascular Systems, is being conducted to gather safety and effectiveness data on the Orbital Atherectomy System (OAS). The OAS is a catheter-based system that uses a diamond-coated crown (the Orbital Atherectomy Device) to remove plaque from peripheral arteries.

The Orbital Atherectomy Device (OAD) is designed for debulking atherosclerotic plaque in coronary and peripheral vessels. The design of the device and its orbital action have the potential to improve the procedural success of vascular interventions while minimising the acute vascular injury and chronic complications typically associated with other atherectomy interventions.

The OAD operates on physical principles unlike those at work in standard rotational atherectomy. Rather than a symmetric rotating burr, the OAD employs a patented, eccentrically shaped wire coil and diamond-coated abrasive crown.When rotated at high speed the abrasive crown moves in an orbital path around the periphery of the lumen, gradually removing small particles of stenotic tissue with each pass across the lesion. The diamond grit size and high rotational speed are designed to help ensure that the ablated stenotic tissue particles are small enough to pass through the coronary capillaries and removed by the body, thus reducing the potential for distal embolic complications.

The orbital motion of the OAD utilizes centrifugal forces to create lateral pressure between the atherosclerotic plaque and the rapidly orbiting diamond-coated abrasive crown, gradually ablating stenotic tissue, debulking the occlusion or lesion and restoring luminal patency while minimizing the deep vascular injury associated with other transluminal interventions.

The eccentric shape of the coil and orbital action of the crown allows for fluid flow and cooling during treatment, minimizing the potential for thermal trauma and ischemia, and related complications.

The first US patient was treated in January of this year by Dr Robert D Safian, co-principal investigator of OASIS, at William Beaumont Hospital in Royal Oak, MI. “The initial experience with orbital atherectomy has been extremely positive. The setup and utilization of the device have been very straightforward and simple. The technology can be easily incorporated into interventional practice after a very brief learning curve,” commented Safian. “The initial results are characterized by excellent angiographic appearance, excellent lumen enlargement, and lack of device-related complications, which is especially notable in this patient population with advanced peripheral arterial disease and high incidence of critical limb ischemia.”