Two new EVAR devices were shown at the VEITHsymposium, in New York, USA. Bolton Medical presented the Treovance stent graft and Endologix released data on its off-the-shelf fenestrated device.
Treovance, Bolton Medical
Bolton Medical presented its new abdominal aortic device, the Treovance abdominal stent graft and Navitel delivery system. The device aims to reduce the potential for limb separation and limb thrombosis and provide accurate device delivery with ease of use.
“We are going to go after a higher degree of angulation and a longer neck of 15mm, so we are going to try to push the limits and try to get something out to help us do things we cannot currently do,” said Mark A Farber, director, Aortic Disease Center, University of North Carolina, USA.
The Treovance abdominal stent graft and Navitel delivery system is a three-piece modular system with a broad range of sizes, with active fixation featuring suprarenal and supplemental infrarenal barbs. Additional device features include flexible main body and legs, telescopic limbs enabling variable limb overlap and step-wise user controlled deployment.
“The device has been designed as a three-piece modular system in a broad range of sizes. It also has a development of an active fixation system with both supra and supplemental infrarenal barbs – so two different regions that we are going to go after in terms of the fixation – it has a highly flexible main body of length and that is to help to accommodate the various anatomies and that is a problem many of us are running into with the current devices not being able to accommodate that issue,” said Farber.
The stent graft offers many bifurcated main body sizes: eight aortic diameters 20–36 mm, three main body lengths 80, 100, 120mm and single leg docking diameter 14mm and several leg extension sizes: seven iliac diameters 8–24 mm, multiple leg lengths 8–18mm and single proximal docking diameter 15mm.
The device will be used in two studies for regulatory approval: ADVANCE, a European study starting in December 2010, and BENEFIT (Bolton Medical Abdominal Stent Graft Trial with Treovance), a prospective multicentre study across five to seven sites across the USA starting in the first quarter of 2011.
Off-the-shelf fenestrated graft, Endologix
The Endologix fenestrated device offers the first possible device to treat acute aortic pathology and a self-contained system to treat complex aneurysm disease. The results of the initial experience with the device to treat pararenal and juxtarenal aneurysms were presented by Daniel G Clair, Cleveland Clinic, Ohio, USA.
“This device was designed to be a complete system to treat juxtarenal aneurismal disease. It is in concert with the bifurcation system that is used with aortic fixation that utilises the Endologix current model of device,” he said.
Inadequate neck is now the most common reason for with complications and failure being two to five times more likely when placing endografts “outside” the instruction for use. The device features a fenestrated proximal extension with oversized midsection and balloon expandable cover stents with ability to flare are placed. The process began with an initial anatomic assessment, design concept, confirmation of design, prototype, testing and revision, animal and pre-clinical testing, flow-model development and device testing and first in man deployment in an 18-month period.
“Currently we use fenestrated grafts to treat these patients but the fact is it takes a while, two to three months to to go through the process of obtaining the grafts and in the US at least, it is limited to IDE sites. There is currently no FDA-approved device and it does not allow us to deal with the acute aortic pathology. For this reason I think this project I’ve been working on for the last 18 months with engineers and Endologix to potentially solve is the most exciting thing to come along in the state of endografting for aneurysm disease in the last 10 years.”
Deployment of bifurcated device took 30–38 minutes, cannulation of renal arteries 15–22 minutes, fenestrated deployment completion took 55–60 minutes, renal stent placement was 25–40 minutes, and fluoroscopic time for the procedures was 45–53 minutes. Total graft placement time was approximately one hour 15 minutes to two hours. There were no intra-operative adverse events.
“The initial experience with this device has been positive and in my estimation this is a radical change in how we treat complex proximal aortic anatomy. It is unbelievable that this device has gone from inception to implant in 18 months and the company has continued tight timelines to hopefully begin implantation in the US in the feasibility trial in the first half of 2011. This offers the first possible device to treat patients with acute complex aortic anatomy with an off-the-shelf system,” Clair concluded.