Medtronic launches Valiant Thoracic Stent Graft at CX Symposium


This follows a tradition of major launches at Charing Cross, with the Gore TAG Thoracic Endoprosthesis launched at the symposium last year.Medtronic claims its Valiant Thoracic Stent Graft with Xcelerant Delivery System provides more options, increased control, and is based on a platform that has a strong history of proven results – essential benefits for physicians to confidently treat challenging thoracic anatomy. In the pre-clinical models the device has shown improved performance, especially regarding key attributes such as conformability, trackability, and deployment. Valiant will address a variety of anatomies with the breadth of sizes and configurations available. Physicians have requested a device that is available with either a proximal bare spring or a closed web, and Valiant will be offered with both configurations to address a wider variety of anatomies. Furthermore, Valiant will be offered in lengths up to 227mm and in diameters from 24 to 46mm. In addition, both straight sections as well as tapered sections will be available. Based on a global experience of more than 16,000 implants worldwide with the Talent Thoracic platform, Valiant is the first endovascular solution with such extensive clinical data as a foundation for design.

Valiant takes the best of the Talent Thoracic device and adds significant improvements. For instance, Valiant is more conformable than Talent Thoracic. The removal of the longitudinal connecting bar and optimisation of stent spacing in the new device allow the device to fit better in anatomies with significant three-dimensional curvature. In addition, the new 8-peaked stent rings on each end (compared to 5-peaks in Talent) more evenly distribute the radial force around the circumference of the aorta, leading to gentler but equally strong fixation as with Talent. The stent rings also have been moved to the outside of the graft. In histological studies of both Talent AAA and AneuRx, Medtronic has found that the aortic wall incorporates the metal structure when the stents are on the outside of the graft, which may assist in long-term fixation. In addition, by moving the stents to the outside, the inner lumen is smoother and more closely resembles a healthy aorta.

Upon completion of testing with physicians, one participant, Professor Christoph Nienaber, from University Rostock, Germany, commented: “The Valiant graft offers a large choice of options with different lengths and proximal configurations. The Xcelerant delivery system allows one to very accurately control the placement of the stent graft. Those advantages, combined with improvements in stent graft conformability give me the confidence to use this graft successfully with my patients.”

In bench testing, the force required to deploy the stent graft was decreased by more than 50% compared to similarly sized Talent Thoracic devices. A coating on the inside of the graft cover helps minimize deployment forces. In addition, the design of the delivery system gives a mechanical advantage that makes the force the physician feels less than 5% of the force felt with Talent deployment. In addition, the tracking force required to advance the delivery system through the iliacs is significantly reduced. This change is due in part to an improved catheter, which tapers towards the handle, reducing the average profile.After performing his first case with Talent AAA with Xcelerant, Professor Wolf Stelter, Chirurgischen Clinic, Frankfurt, Germany said, “The new Xcelerant Delivery System is a big step forward in terms of deliverability and ease of use.” Professor Stelter and his partners successfully performed the first implant of the Xcelerant Delivery System in Europe as part of the Xcelerant Clinical Trial.

Xcelerant has been optimised even further, for thoracic use, from its design for Talent AAA and AneuRx. Its newest version is designed to minimise kinking of the catheter within the section in which the graft is held and a new stent stop makes release from the delivery system even easier. In addition, the Xcelerant tip is a centimeter shorter than the CoilTrac tip and more flexible, allowing Xcelerant to effectively deliver the stent graft into a broader range of anatomies. The radiopaque markers in Valiant also have been improved compared to Talent Thoracic. The distal end markers now have a different shape to help distinguish which end a physician is examining in patients in whom multiple sections have been used.

Used in more than 16,000 implants worldwide, Talent Thoracic has had more clinical use than all other products on the market combined. The same materials are also used in Talent AAA, which has more than 20,000 implants worldwide. Recently at ISES, Professor Rossella Fattori presented data on the Talent Thoracic retrospective Registry (TTR), which included more than 450 patients and had follow-up for patients of up to 84 months. As long-term data on Talent Thoracic continues to emerge, physicians can increasingly trust the materials in this stent graft. Given the clinical success of Talent Thoracic, Valiant has been designed to use the same durable materials. In addition, by using these same materials, Valiant (like Talent) continues to be both MRI-safe and MRI-compatible. As younger trauma patients are increasingly being treated, MRI safety has also become increasingly important.

Following recent CE mark approval, training for initial sites for the Valiant launch has begun and the first implants of the Valiant Thoracic Stent Graft with Xcelerant Delivery System are planned to occur during Spring 2005. Over the next year, Valiant will be rolled out to most countries in which Talent Thoracic has been available. In the US the VALOR trial for Talent Thoracic continues to enrol and Medtronic intends to support the continued expansion of use of thoracic stent grafts. The company will be sponsoring clinical studies to learn about potential advantages of endografting. For example, in Europe, the INSTEAD study continues to enrol patients. The company also has plans to explore the health economics of thoracic endografting compared to open procedures. Finally, Medtronic has also begun market research for the thoracic endograft that will be Valiant’s successor.

“We partnered with more than 100 of the world’s leading endovascular clinicians to analyse outcomes and conquer thoracic challenges,” remarked Jim Moriarty, Director of Research and Development for the endovascular program at Medtronic. “The result is a durable solution with a choice of fixation options, multitude of lengths and diameters, increased conformability and improved deliverability that allows controlled deployment. The Valiant System is well-positioned to be a very competitive device.”

Also at the Charing Cross Symposium, trial results from the TAG (Michael Makaroun, Pittsburgh, USA), the VALOR (Ron Fairman, Philadelphia, USA), and the TX2 (Jon Matsumura, Chicago, USA) pivotal trials will be presented at the Global Endovascular Forum, on Sunday 10th April in the Sherfield Building.

Cook will also showcase its Zenith TX2 Thoracic TAA Endovascular Graft, which incorporates clinically proven technologies to treat life-threatening thoracic aortic aneurysms (TAA) without the need for traumatic open surgical repair. The system received the CE mark in January 2005. The system allows the physician to choose the proper size for each part of the Zenith TX2 Thoracic TAA Endovascular Graft so that it will fit the aorta where the aneurysm is located. Before the graft is implanted, each of its two parts is contained in a H&L-B One-Shot Introduction sheath.

The Zenith TX2 system requires an incision to insert the graft’s hydrophilic, kink-resistant delivery system into the femoral artery in the leg. Once the system is guided into position through the patient’s arteries under fluoroscopy, a one- or two-piece, fabric-covered, self-expanding stent graft is placed inside the weakened section of the thoracic aorta to relieve pressure on the aneurysm, helping to reduce the risk of rupture.

The introduction system allows the graft to be inserted and accurately placed in the correct position in the aorta. The plastic tubes are removed after the graft is put in place. Clinical experience with this device suggests that the system permits treatment of many thoracic aneurysms without the need for major open surgery. The system is approved for commercial distribution in Canada, Australia and Asia.

Cook is currently conducting the STARZ-TX2 trial (Study of Thoracic Aortic Aneurysm Repair with the Zenith TX2 Thoracic TAA Endovascular Graft), a North American trial approved by the FDA to study the safety and effectiveness of the Zenith TX2 Thoracic TAA Endovascular Graft in the treatment of thoracic aortic aneurysms.

Kem Hawkins, President and CEO of Cook Incorporated said, “Cook’s technology for treating aortic aneurysms has earned the Zenith stent-graft family of devices a reputation for safety and clinical performance unmatched in the industry, and we’re thrilled to have begun US clinical trials with the newest generation of Zenith grafts to treat thoracic aneurysms. In the coming months, our company will unveil the most innovative and exciting line of new products ever developed for treating aortic aneurysms. Using our newest Zenith technologies, physicians can bring the benefits of minimally invasive, endovascular treatment to thousands of aneurysm patients who would otherwise have had to forego treatment. We look forward to the successful launch of this companion product line to our highly respected Zenith AAA Endovascular Graft system.”

BARD Peripheral Vascular will also launch their Dynaflo Bypass Graft at this year’s Charing Cross Symposium. Designing grafts for different applications will be discussed in the Bard Satellite Symposium titled ‘Dynamic Solutions to the Challenges of Graft Design’ on Sunday 10th April at 13.00.