An Introduction to Atherectomy Systems
Atherectomy devices are used in the cath lab to debulk lesions by cutting or laser ablating plaque, calcium and tissue hyperplasia from vessel walls, allowing recanalization of the vessel lumen as an end in itself, or in preparation for stenting. While some devices have an indication for the coronaries, the primary use of these devices is for peripheral artery disease (PAD) in the legs.
Healthcare providers are increasingly viewing PAD as a progressive, chronic disease that requires a continuum of treatment, where few patients are treated only once. Many are treated to restore flow whenever the disease re-occludes a vessel, or a new vessel develops a blockage. The goal is to improve quality of life and prevent amputation.
Treatments that restore bloodflow without reducing the ability to treat the vessel in the future are better suited for PAD. Atherectomy is seen by many as an ideal therapy for PAD because it can restore flow while removing the plaque burden and does not leave behind a permanent obstacle to future treatments, such as a stent. Stenting in the legs leads to frequent restenosis or fractured stent struts, and can be problematic or prevent repeat interventional or open surgical repairs.
Cost of treatment is always a concern for both reimbursement and institutions. Atherectomy may be a less costly approach to PAD over the life of a patient than open surgery or ballooning and stenting. Within the atherectomy market, the vendors must demonstrate both economic advantages and procedural success. The total cost (including the number) of devices needed for a procedure, the duration of lumen patency and reduction of side effects that require additional treatments influence use of these technologies.
Cardiovascular Systems Inc. (CSI) recently shared 12-month data from the COMPLIANCE 360° study of severely calcified above-the-knee lesions. The prospective study of 50 patients (with 65 lesions) at nine U.S. sites randomized patients equally to balloon angioplasty alone versus the Diamondback Orbital Atherectomy System with adjunctive ballooning. The study showed that avoiding stents and reducing restenosis saved money. The approximate incremental cost savings of the atherectomy group at six months was $5,264 per additional acute adjunctive stenting or restenosis avoided. The study also found the angioplasty arm required bailout stenting in 84 percent of the procedures to achieve results equivalent to the Diamondback arm.
There is increasing interest in atherectomy treatments in vessels below the knee. Successfully recanalizing arteries to the ankle and foot can reduce pain, restore mobility and reverse ulceration, which may have a major impact on the costs of chronic wound care in lower extremities.
There was a setback for coronary atherectomy with the results of the ROTAXUS (A Prospective, Randomized Trial of High-Speed Rotational Atherectomy Prior to Paclitaxel-Eluting Stent Implantation in Complex Calcified Coronary Lesions) trial, presented at the 2011 Transcatheter Cardiovascular Therapeutics (TCT) symposium. The trial found the process was not superior to standard balloon angioplasty and decreased the efficacy of the stent in reducing new tissue growth within the blood vessel.
Drug-eluting stents (DES) are liberally used in complex lesions. Heavily calcified stenoses have not been adequately studied, and form a challenge for immediate and late outcomes. Rotational atherectomy has been shown to effectively modify calcified plaques and facilitate stent delivery and expansion. In patients with complex calcified lesions, rotablation followed by DES seems a rational combination, but there was a lack of evidence prior to the ROTAXUS trial.
Boston Scientific - www.bostonscientific.com
Covidien - www.turbohawkdevice.com
Cardiovascular Systems Inc. (CSI) - www.csi360.com
Spectranetics - www.spectranetics.com